Universal Connector

A connector system is provided for an apparatus intended to be walked on, swung on or jumped on in use. The connector system comprising a plurality of frame elements, each comprising an insertion portion, at least one protrusion, and frame element rotation reducing portions. Also provided is a plurality of first connector members, each configured to receive the insertion portion of at least one frame element into a channel therein. There are also a plurality of second connector members, each configured to mate with one first connector member, whereupon insertion of the insertion portion of at least one frame element into one first connector member, and mating of the one first connector member with one second connector member, the frame element cannot be removed from the first connector member due to the at least one protrusion of the frame element engaging with the second connector member; and the frame element is substantially unable to rotate in the first connector member due to the rotation reducing portions engaging with the channel of the first connector member.

The present document claims priority from AU2021904293 entitled Universal Connector filed on 29 Dec. 2021; AU2022902135 entitled Universal Connector filed on 29 Jul. 2022 and AU2022902938 entitled Universal Connector filed on 7 Oct. 2022 the contents of each of which are hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a connector for connecting frame elements such as rods, tubes or pipes. In an embodiment, the connector is used to connect frame elements of an apparatus that is intended to be walked on, swung on or jumped on in use. The apparatus could be a playground apparatus such as a climbing frame or a trampoline.

BACKGROUND

When building a large structure, it is sometimes necessary to connect multiple pieces together. In the building industry, for example, a large structure of scaffolding can be required to accommodate access to a structure being built. The scaffolding comprises multiple rods or tubes connected to one another to provide a frame around the building. Construction workers will stand, move and work on the scaffolding during the day. Therefore, it is important that the scaffolding frame once in place is strong, robust and that the points of connection are unlikely to fail in use.

Other large structures that take the weight of persons in use include climbing frames, bunk beds and trampolines. A climbing frame can be formed from multiple rods or tubes connected to one another to provide a frame around which a child can swing and play. The child may climb, swing and jump around the frame and sometimes multiple children put all their weight on the structure at once. It is important that the frame is structurally robust and does not break, sway or loosen especially at connection points.

To provide optimum structural integrity to a frame, the number of joints in the frame can be minimised. The joint parts of the frame structure can be welded or otherwise permanently joined to form a connection that is immovable and unlikely to fail in use. However, there are circumstances where permanent joints are not appropriate. For example, in scaffolding, a permanent joint is not appropriate because the scaffolding should be removed once it is has served its purpose. In domestic playground apparatus, permanent joints may not be appropriate because the user may wish to disassemble the apparatus and move it when they e.g., re-design their backyard area, dispose of the apparatus, or move house. If the domestic playground apparatus is permanently assembled, the user's ability to relocate/resell the product is reduced, because the owner is not able to disassemble it and transport it to another location.

With it in mind that some structures need to be readily transportable and easy to assemble and disassemble, a means of connecting frame parts together becomes essential. Long pieces permanently joined together is no longer an option. Instead, pieces of the frame that are required to be long in length can come in smaller parts, each of which smaller part can be connected to the other to form an overall longer piece. For example, in a trampoline, the elongate tubular frame parts of the steel frame are often modular. Smaller frame elements can be connected together to make the overall frame structure. In children's climbing equipment such as monkey bars, the frame can be made from smaller frame pieces connected together to make the overall frame structure. In scaffolding, the tube parts used to form the scaffold frame can be connected together to form an infinitely extendable scaffolding that can grow with the building as more scaffolding is required. The tubular frame parts can be connectable along the same longitudinal length to make long frame elements as described. Furthermore, the tubular frame parts are desirously connected at the corners and or at other locations within the structure, so that the frame can take shape.

Turning back to trampolines, providing stability in a trampoline frame is a challenge since it is intended to be jumped on. For many years recreational trampolines have typically included a tubular steel frame which is supported on spaced apart legs with a flexible jumping mat secured to the frame by a large number of spaced apart extension springs which extend and contract as a person jumps on the mat in order to give “bounce”. The springs are usually connected to the tubular steel frame at one end via radial slots provided therein and to the mat via hooks or the like at the other end. Although trampolines can be made in many shapes, circular is probably the most popular in which case the frame is generally constructed of arcuate segments of round tube which are joined together in a spigot and socket arrangement with the end portion of one segment sliding into the end portion of the adjacent segment. Whilst a spigot and socket arrangement is generally useful, over time and following use, the spigot can tend to become wedged into the socket and the only means to remove it can be force. Sometimes tools are required to separate the spigot from the socket, which is not desirable. Furthermore, where the mat support frame joins to the vertical support frame elements such as the legs of the trampoline, the connection should be robust and strong. A connector that can securely join frame pieces and which does not require force to disassemble is preferred for the domestic market.

Accordingly, there exists a need for joining frame elements that allows for the building of robust structures that do not sway or loosen at connection points even under the application of intended user load. Furthermore, the means of joining the frame elements should allow for relatively easy disassembly even after a period of prolonged use. It would also be advantageous if the connector was a universal connector that allowed for the joining of multiple types of frame elements so that the user has improved choice when designing bespoke structures. It would also be advantageous if the connector was fun to use during construction.

The present invention is aimed at providing an improved connector which can ameliorate at least some of the problems of the prior art or which can provide a useful alternative.

SUMMARY OF INVENTION

According to a first aspect there is provided a connector system for an apparatus intended to be walked on, swung on or jumped on in use, the connector system comprisinga plurality of frame elements, each frame element comprising an insertion portion comprising at least one protrusion; and frame element rotation reducing portions,a plurality of first connector members, each first connector member configured to receive the insertion portion of at least one frame element into a channel therein;a plurality of second connector members, each second connector member configured to mate with one first connector member,whereupon insertion of the insertion portion of at least one frame element into one first connector member, and mating of the one first connector member with one second connector member,the frame element cannot be removed from the first connector member due to the at least one protrusion of the frame element engaging with the second connector member; andthe frame element is substantially unable to rotate in the first connector member due to the rotation reducing portions engaging with the channel of the first connector member.

The connector system can therefore provide a structurally stable frame assembly that is substantially more rigid that other frame assemblies that do not make use of the connector system. It is thought that by substantially preventing rotation of each frame element, and by substantially preventing removal of each frame element from the connector (comprising the first connector and the second connector), the rigidity of the frame is increased compared to the same frame without the connector assembly described.

In another aspect there is provided a connector system for frame elements, the connector system comprisinga frame element comprising an elongate body with a longitudinal axis, the elongate body having a first end and a second end, wherein at one or both of the first end and second end of the elongate body there is provided an insertion portion, the insertion portion comprising a protrusion or series of protrusions around the outside periphery of the frame element, the protrusion or series of protrusions around the outside periphery of the frame element having a first side and a second opposing side and providing a portion of increased diameter on the insertion portion;a first connector member having an outside surface and an inside surface, the inside surface defining a channel therein, the channel having a rear wall and a front wall, the front wall defining an opening, wherein the insertion portion of the rod or tube can be inserted through the opening into the channel, wherein the frame element is insertable into the channel until either of the first end of the frame element contacts the rear wall which prevents further insertion movement of the frame element, or the first side of the protrusion or series of protrusions contacts the front wall of the first connector member and the frame element is thereby prevented from further insertion movement into the channel;a second connector member that can be brought into contact with the first connector member inserted into the channel, the second connector member comprising a barrier wall that once in place can abut the second side of the protrusion or series of protrusions, the second connector member further comprising a connection assembly associated with the barrier wall and configured to engage the second connector member to the first connector member so that the protrusion or series of protrusions is/are sandwiched between the first connector member and the second connector member, wherein the frame element cannot be removed from the connection system until the second member is disengaged from the first connector member;wherein the insertion portion of the frame element comprises a series of frame element rotation reducing portions which mate with an inside surface of the channel of the first connector to prevent or at least reduce rotation of the frame element once inserted into the first connector member.

In an embodiment, the frame element rotation reducing portions are longitudinal axially fixed indexed splines. There may also be first connector rotation reducing portions in the form of longitudinal ribs on the inside surface of the first connector, which provide grooves between them which mate with the axially fixed indexed longitudinal splines, to thereby substantially prevent rotation of the frame element.

The spline on the frame element is similar to that used in a drive shaft for example in a car or truck. Splines are essentially ridges or teeth on a drive shaft that match with grooves in a mating piece and transfer torque to it, maintaining the angular correspondence between them. In these well-known applications, the spline can resist or transmit rotational forces measured as torque. At the same time the spline in a drive shaft is designed to allow axial movement with little resistance. This is important so that as the shaft changes angular position through a coupling, the axial distance may change. The most common example of this is the drive shaft to the rear axle assembly of a car or truck. When moving up and down, there are changes in the angle of the drive shaft and it also moves the shaft forward and back a small amount axially. The sliding action removes conflict of the slightly changing length of the shaft. Also, a spline in a drive usually allows the same number of possible mating connections as the number of teeth used.

The present axially fixed indexed splines are a unique spline connection that while resisting rotational movement from the mating connections, also resist axial movement by using a barrier wall provided forward of the front wall of the longitudinal spline teeth. The barrier wall axially fixes the splines. This is a new and unique way of using a spline mating connection that makes the connection suitable for use in fixed joints. The connector is easy to assemble by being a close fit without resistance, yet the interlock feature prevents axial movement when locked in position.

Another unique feature of the present axially fixed indexed spline connection is indexing. Whereas splines have a number of teeth in the mating connections, these normally have no relevance with respect to which mating alignment is used. However, in the present connector, the mating is used for angular indexing. For example, in an eight-tooth spline there is provided for fixed connections to be connected at 45 degrees, 90 degrees, 135 degrees, 180 degrees, 225 degrees, 270 degrees and 315 degrees. This allows for frame structures to be created with instruction that are many and varied whilst remaining indexed.

In yet another aspect there is provided a connector system for frame elements, the connector system comprisinga frame element comprising an elongate body with a longitudinal axis, the elongate body having a first end and a second end, wherein at one or both of the first end and second end of the elongate body there is provided an insertion portion, the insertion portion comprising a protrusion or series of protrusions around the outside periphery of the frame element, the protrusion or series of protrusions around the outside periphery of the frame element having a first side and a second opposing side and providing a portion of increased diameter on the insertion portion;a first connector member having an outside surface and an inside surface, the inside surface defining a channel therein, the channel having a rear wall and a front wall, the front wall defining an opening, wherein the insertion portion of the rod or tube can be inserted through the opening into the channel, wherein the frame element is insertable into the channel until either of the first end of the frame element contacts the rear wall which prevents further insertion movement of the frame element, or the first side of the protrusion or series of protrusions contacts the front wall of the first connector member and the frame element is thereby prevented from further insertion movement into the channel;a second connector member that can be brought into contact with the first connector member inserted into the channel, the second connector member comprising a barrier wall that once in place can abut the second side of the protrusion or series of protrusions, the second connector member further comprising a connection assembly associated with the barrier wall and configured to engage the second connector member to the first connector member so that the protrusion or series of protrusions is/are sandwiched between the first connector member and the second connector member, wherein the frame element cannot be removed from the connection system until the second member is disengaged from the first connector member;wherein the first connector member comprises a series of teeth arranged around the periphery of the outside surface of the channel, and the second connector member comprises at least one ratchet arm, engageable with teeth during connection of the second connector member to the first connector member; wherein the connector system is thereby configured to generate an aural indicator as the second connector member is screwed onto the first connector member.

The connection system of the present invention can be used with any frame elements including rods, tube, pipes, poles and bars. The frame elements can be solid or hollow. Typically, the frame elements are hollow to minimise costs in manufacture and to provide a cost saving in weight. The frame elements to be connected can be those typically used in the scaffold or play equipment industry, and which are then modified by the connector system or connector assembly of the present invention. In an embodiment, the frame elements are themselves modified for use with the present connector system. The frame elements can be used to build any structure including but not limited to playground frames such as monkey bars, scaffolding, beds, tents, trampolines, swing sets, and so on.

Each frame element such as rod or tube, for exemplary purposes, can have an elongate body. The body can be straight or curved. The body of the frame element can have any cross-section. The most typical cross-section for frame elements is circular, although the invention is not limited to frame elements of this shape. In an embodiment, the cross section is at least about 40, 45, 48 mm in diameter. In an embodiment, the cross-sectional distance of the frame element is 44.5 mm. The frame elements can be made from any material. In an embodiment, the frame elements are made from metal. The elongate body can have a first end and a second end. The first end and the second end can be identical except in the case of frame elements where the thickness or shape of the frame element changes along its length. The first end of the frame element can be for joining with the second end of another, separate frame element. The second end of the frame element can be for joining with the first end of another, separate frame element. The first ends and the second ends can in principle be joined together in perpetuity. However, at some point, there may be a natural end of the structure, which will result in an end of a frame element that is not joined to another frame element. The ends of the frame elements which are not joined to other frame elements can be capped. There may be no free ends if the structure is such that all ends of the frame elements are connected, such as in a cuboidal shape.

The end of the frame element that will join with the connector can have an insertion portion. The insertion portion is intended for insertion into the body of the first connector. The insertion portion can be of any length. If the insertion portion is too short, there is a risk that the point of connection is not strong enough and the frame element may move too much in the first connector. It is preferred that the insertion portion is at least equal in distance along the frame element to the diameter of the frame element. For example, if the diameter of the frame element is N cm, then the insertion portion is at least equal to N cm. In some embodiments, the insertion portion is at least about twice, 5, 10 or 15% greater in length than the diameter of the frame element. If the frame element is not round (and therefore has no diameter) then instead of the diameter, the distance can be measure as the longest length from one side of the cross section to the other e.g. in a square, the diagonal distance from opposing corners.

In an embodiment, the insertion point can comprise one or more protrusions around the frame element body. The function of the protrusion(s) is to provide a part of the frame element that can be gripped between the first connector and second connector members in use. In an embodiment, the protrusion(s) on the frame element can be identified as the part which stops the insertion portion from being further inserted into the channel. Alternatively (or in addition), the protrusion(s) can be identified as the part that abuts the barrier wall of the second connector member and substantially prevents or at least reduces removal of the frame element from the first connector member.

In an embodiment, the insertion portion is different in diameter to the remainder of the elongate body of the frame element. This can be useful where the insertion portion slides into the first connector member and is secured into position by a second connector member where the outside surfaces of the elongate body of the frame element and second connector member can be substantially flush with one another. There can be some step in the change between surfaces. However, being as flush as possible can provide a more aesthetically pleasing join that is also functionally useful if, e.g. something needs to slide along connected frame elements.

In a frame element with a substantially circular or ovaloid cross section, where there is a single peripheral protrusion, the protrusion can be referred to as a circumferential protrusion. In frame elements with other shapes, such as triangular, the formation of a protrusion around the outside surface can be referred to as circumferential, even though it will be appreciated that it is not circular in shape.

Nevertheless, the protrusions can trace around the outside of the frame element body and provide an area of increased diameter or increased cross sectional width for the frame element. The increase in cross sectional area can be relative to the remainder of the body of the frame element that does not comprise the protrusion(s).

There can be one circumferential protrusion. In the case of a frame element with a circular cross-section, the protrusion can be an annular ring. The ring can be a solid shape with squared edges. The ring can have rounded edges. There can be a preference for solid edges as will become apparent from the description herein, since the protrusions will thus be sandwiched without air spaces between the first and second connector members if they have squared edges. Since the function of the protrusion is to provide an area of increased diameter on the frame element, the protrusion does not have to be a solid ring around the element body and instead it can be provided in parts. Where the protrusion is provided in parts it can be referred to as a series of protrusions around the outside periphery of the frame element. The series of protrusions can be of any shape such as knobs, squared, rectangular columns, other. Each protrusion can be formed into the material of the frame element e.g. by moulding, pressing or crimping. Each protrusion can be material added to the frame element e.g. by adhering a solid piece or adding a rivet. The protrusion(s) can be hollow. The protrusion(s) can be solid. There can be any number of protrusions around the outside periphery in a series including 2, 3, 4, 5, 6, 7, 8, 9 or 10. If there are too many protrusions, the risk is that they become a point of weakness since the surface area joining them to the underlying structure gets less and they could break off more easily. The protrusion(s) whether in single form or parts can be formed by or accompanied by longitudinal splines can be axially fixed and which allow for indexing of the frame element with the first connector. The axially fixed indexed splines extend along at least a part of the longitudinal length of the insertion portion. The protrusions can be the leading edges of the axially fixed indexed longitudinal splines. These splines can assist with decreasing rotation of the frame element once inserted into the first connector member if there are corresponding grooves between complementary ribs inside the channel of the first connector to reduce rotation.

In an embodiment there are a plurality of axially fixed longitudinal splines around the outside periphery of the insertion portion. Each spline can be in one single piece. Each spline can be formed in multiple pieces with lands between elongate spline parts. Each spline can be at least or at most 2, 3, 4, 5, 6, 7 or 8 mm (or larger) in thickness from one side of the spline to the other. The spline can be formed in two or more longitudinal spline parts to reduce the amount of material used to form it. The spline can be across 75, 80, 85, 90, 95 or 100% the distance of the insertion portion. Although there should be at least some part of the insertion portion free from the location of the barrier wall of the second connector member. Each spline can have an elongate axis substantially aligned with the longitudinal axis of the frame element; this is the most straightforward arrangement since the frame element is most easy to insert into the first connector member. In an alternative embodiment, each spline is offset with respect to the longitudinal axis of the frame element. In this embodiment, the arrangement is slightly more complicated because the receiving channels for the offset splines still need to be able to receive and mate with them to prevent or reduce rotation. In an embodiment with angled offset splines, the channels for receiving them will need to be wider, which results in less overall contact between frame element and first connector. There is still likely to be an overall reduction in rotation, but the optimum reduction is where straight splines contact with straight ribs in the channel of the first connector. In an embodiment, the splines could be curved so that they mate with the corresponding parts of the first connector member upon rotational insertion into the first connector member.

In order that the splines are repeatedly matingly received into a first connector member it is preferably that each spline is the same. The splines can be the same across multiple frame elements, so any frame element can be mated into any first connector. In an embodiment, the splines can be different around a single frame element so that there is only one way in which they can possibly be inserted into a correspondingly shaped first connector member. This would increase complexity during construction but may provide some advantages such as forcing a particular orientation of respective frame elements relative to one another.

There can be any number of splines around the outside periphery of the insertion portion. There could in principle be a single spline with a corresponding channel on the inside surface of the first connector member; however, to optimise a reduction in rotation of the frame element in the first connector member, preferably there are splines all the way around the outside of the insertion portion. The splines can be equidistant from one another. There can be at least or at most 3, 4, 5, 6, 7, 8, 9, 10 or more splines. It is noted that with frame elements in which there is a bend or an elbow, the insertion of the insertion portion of the frame element into the first connector member needs to be in a particular way in order that the frame element lines up with other connectors. This indexing of the splines as they are mated into the first connector means that sometimes the frame element has to be inserted in a particular way for a frame to be formed. If there are too many splines, a chance that the frame element with an elbow is not oriented in the correct way are increased and the user has to keep removing the insertion portion and trying again to achieve the correct assembly. With this in mind, it is considered that about eight splines is optimal for reducing rotational movement between the frame element and the first connector member and for ease of construction.

Each spline has a first longitudinal side and a second longitudinal side. When the insertion member of the frame element is inserted into the first connector member the spline can slide into a channel or groove formed in the inside wall surface of the first connector member. Each elongate spline receiving groove in the channel in the first connector member can be formed between longitudinal ribs. Each rib of the first connector member can have a first side and a second side. The first side of the rib can abut with the first longitudinal side of a spline once the spline has slid into the groove and the two are unable to pass over one another. This means that rotational forces applied to the frame element are absorbed by the splines and ribs and the frame element is prevented or substantially reduced from rotating inside the first connector member.

In an embodiment there can be a single protrusion that does not cover the entire circumference (or periphery) of the frame element. Nevertheless, the protrusion can act to provide a part of the frame element that can be gripped by the first connector and second connector members in use. It should be understood that such a single protrusion is in scope but may not be preferred due to the decreased amount of surface area for gripping for the first and second connector members.

The amount that the protrusions extend from the frame element surface can vary. However, the protrusion or protrusions should not be so short that they are unable to provide a good functional surface for gripping by the connector members; or so that there is a risk that the insertion portion could be pushed too far into the first connector and get stuck. On the other hand, the protrusion or protrusions should not extend out so far that they are unsightly, difficult to manufacture, hamper handling and generally cause a nuisance. In a preferred embodiment, the protrusion(s) increase the diameter of the frame element by about 10 to about 20%, more preferably about 15 to about 18% from the original diameter of the frame element. For example, if the diameter of the frame element is 5 cm, the protrusion(s) can extend about 0.5 cm to thereby increase the overall diameter by 1 cm (about 20%). If the diameter of the frame element is 3.5 cm (measured from outside wall) then the diameter of the frame element can be increased to about 3.9 cm by the protrusions (about 10%).

While there may be multiple protrusions referred to, it should be understood that one protrusion is in scope so that section can be read as a singular protrusion unless the context makes clear otherwise.

The protrusions can be provided on the frame element. In this embodiment, the frame element is manufactured with the protrusion(s). Thus, the protrusions are integral with the frame element and cannot be removed from the frame element. Alternatively, the protrusions are provided on an element that is attachable to the frame element. For example, the end of the frame element could be capped with a sleeve that has a part of it comprising one or more protrusions around its outside periphery. Where the insertion portion is a cap, it can be made from a different material to the rest of the frame element. The cap can slide over the end of the frame portion and be secured around the outside wall. The cap can slide into the frame portion and be secured to the inside wall. The cap can be secured to the frame element by any means. The cap could be secured to the frame element by tight interference fit. To increase structural integrity, the cap could be secured to the frame element by crimping and or by fasteners. In a preferred embodiment, however, the insertion portion is moulded on the end of the frame element during manufacture, since this increases structural integrity by providing a single unitary piece and reduces overall unit cost.

The end of the insertion portion can be open. The end of the insertion portion can be closed. If the insertion portion is formed from a cap, the end can be closed during manufacture. Where the end of the insertion portion is a moulded tube, the end will necessarily be open. To close the open end for aesthetic purposes, or for safety to ensure that rough edges are protected, there can be provided a capping button. The capping button can be secured by any means including a tight interference fit. The capping button could be marked with words, logo, or other information as desired.

Whether there is one or more protrusions, whether they are integral with the frame element or provided in a separate piece, the protrusions comprise a first side and a second opposing side. Upon insertion of the insertion portion of the frame element into the connector, the first side of the protrusions is facing forward towards the first connector. The second side of the protrusions is thus facing outwardly once the frame element is engaged with the first connector.

In a second aspect of the invention there is provided a connection system for rod and or tube-like frame elements, the connection system comprisinga frame element such as a rod or tube comprising an elongate body having a first end and a second end, wherein at one or both of the first end and second end of the elongate body there is provided an insertion portion comprising an indentation or series of indentations located around the outside periphery of the rod or tube, the indentation or series of indentations around the outside periphery of the rod or tube providing a portion of decreased diameter when compared to the insertion portion and the remainder of the elongate body of the rod or tube,a first connector member having an outside surface and an inside surface, the inside surface defining a channel therein, the channel having a rear wall and a front wall, the front wall defining an opening, wherein the insertion portion of the rod or tube can be inserted through the opening into the channel,wherein the channel further comprises a protrusion or series of movable protrusions, the movable protrusion or series of movable protrusions being movable between a retracted position in which the rod or tube can be inserted into the channel, and an engaged position in which the protrusion or series of protrusion are located in the indentation or series of indentations provided in the rod or tube, the protrusion or series of protrusions thereby preventing removal of the rod or tube from the channel. Optionally, a second connector member is provided that can be brought into contact with the first connector member once the rod or tube has been inserted and engaged with the channel, the second connector member may comprise a connection assembly configured to engage the second connector member to the first connector member.

Description relating to the first aspect of the present invention also applies to the second aspect of the invention unless the context makes clear otherwise. For example, the connection system of both the first and second aspects of the present invention can be used with any frame elements including rods, tube, pipes, poles and bars. The frame elements of both the first and second aspects can be used to build any structure including but not limited to playground frames such as monkey bars, scaffolding, beds, tents, trampolines, swing sets, and so on.

In this embodiment, the insertion portion comprises one or more indentations around the frame element body. The function of the indentation(s) is to provide a part of the frame element that can be gripped by the first connector in use. In a frame element with a substantially circular or ovaloid cross section, where there can be a single peripheral indentation, the indentation can be referred to as circumferential indentation. In frame elements with other shapes, such as triangular, the formation of an indentation around the outside surface can be referred to as circumferential, even though it will be appreciated that it is not circular in shape. Nevertheless, the indentation can trace like a channel around the outside of the frame element body and provide an area of decreased diameter or decreased cross sectional width for the frame element. There can also be indentations arranged longitudinally along the insertion portion of the frame elements body.

There can be one circumferential indentation. In the case of a frame element with a circular cross-section, the indentation can be an annular ring. The ring can be a solid channel with squared edges. Since the function of the indentation is to provide an area of decreased diameter on the frame element, the indentation does not have to be a solid ring around the element body and instead it can be provided in parts. Where the indentation is provided in parts it can be referred to as a series of indentations around the outside periphery of the frame element. The series of indentations can be of any shape such as inverted knobs, squared, rectangular column channels, other. There can be any number of indentations in a series including 2, 3, 4, 5, 6, 7, 8, 9 or 10.

In an embodiment there can be a single indentation that does not cover the entire circumference (or periphery) of the frame element. Nevertheless, the indentation can act to provide a part of the frame element that can be gripped by the first connector in use.

The amount that the indentation(s) extend into the body of the frame element surface can vary. However, the indentation(s) should not be so short that they are unable to provide a good functional surface for gripping by the protrusion provided on the first connector member. In a preferred embodiment, the indentation(s) decrease the diameter of the frame element by about 10-20% from the original diameter of the frame element. For example, if the diameter of the frame element is 5 cm, the protrusion(s) can extend about 0.5 cm into the frame element thereby decreasing the overall diameter by 1 cm (about 20%). In the alternative, the indentations are provided as openings in the frame element wall with no closed bottom wall.

While there may be multiple indentations referred to, it should be understood that one indentation is in scope so that section can be read as a singular indentation unless the context makes clear otherwise.

The indentations can be provided on the frame element. In this embodiment, the frame element is manufactured with the indentation(s). Thus, the indentations are integral with the frame element and cannot be removed from the frame element. Alternatively, the indentations are provided on an element that is attachable to the frame element. For example, the end of the frame element could be capped with a sleeve that has a part of it comprising one or more indentations around its outside periphery.

Whether there is one or more indentation, whether they are integral with the frame element or provided in a separate piece, the indentations are configured to receive protrusions from the inside of the first connector member. Advantageously, the protrusions from the inside of the first connector member have a complementary shape, to provide a tight fit once engaged. However, provided there is some protrusion located into the indention, the unwanted removal of the frame element can be avoided. In an embodiment, there is a single indentation on the frame element, and the first connector member comprises a single protrusion that is movable into and out of the indentation. In an embodiment, there is an annular indentation on the frame element, and an annular protrusion located in the first connector element that is movable into and out of the annular indentation. The or each protrusion can be manually moved from the unlocked (retracted) to the locked (engaged) position with respect to the respective indentation. In an embodiment, the protrusion is spring biased into the channel and must be manually removed from the channel of the first connector member using a protrusion mover in order to locate the frame element. In an embodiment, the protrusion is spring biased out of the channel of the first connector member and must be manually forced into the channel using a protrusion mover in order to locate the frame element. The insertion portion so described in this embodiment can be equipped with the splines described above.

The connector of the present invention comprises a first connector member (sometimes referred to as a first connector) operable with a second connector member (sometimes referred to as a second connector). The first connector member comprises an outside surface which is accessible and manipulatable. The first connector member has an inside surface which is the wall defining the interior of a channel. The inside surface wall can be smooth. The channel inside the first connector can be integrally formed with the wall of the first connector. The first connector member can be provided by an insert that slides into a tube to form the first connector. To join the insert with the tube and prevent unwanted movement of it out of the tube during use, the tube and connector can be crimped together or otherwise fastened.

In an embodiment, the first connector member is a separate handleable piece into which a frame element can be inserted. Where a connector has two (or three) first connector members the piece can be made and stored separately to the frame element. The frame elements for use with such connectors can have an insertion portion at each end of the frame element. In other embodiments, where a frame element to frame element join is required, the frame element can have an insertion portion at one end, and a first connector member at the other end. The first connector member can be held into the end of the frame element by tight interference fit. However, to further ensure absolutely no removal of it in use, there can be other securing means of the first connector into the end of the frame element such as by using glue and or taper. Furthermore, the first connector member can comprise a sleeve which slides into the frame element. The sleeve can comprise an indentation. A complementary protrusion can be formed into the frame element to conform to the indentation in the frame element. The protrusion/indentation can be circumferential. The pieces can be crimped together to ensure that one is not readily removable from the other in use.

The channel in the first connector is configured to allow insertion of the insertion portion of the frame element. The channel can be slightly wider than the insertion portion of the frame element to ensure that it can fit therein. In a preferred embodiment, the channel is about the same diameter as the frame element so as to allow a tight interference fit. Once inserted into the channel, the frame element, subject to what shape it is, may be able to rotate in the channel unless there are means which prevent that rotation. As noted above, in order to prevent or at least reduce any unwanted rotation, the inside surface of the channel can be modified with rotation reducing portions to engage the frame element. The first member rotation reducing portions can be ribs forming channels in the channel wall. The ribs can be received into complementary recesses between splines, as described, provided on the frame element. The frame element would thus be substantially prevented from rotating in the channel since the ribs and splines would not allow for rotational movement. The frame element itself is thus also modified with frame element rotation reducing portions. In an embodiment the frame element rotation reducing portions are provided on a frame element that is modified with a cap that provides the protrusion or series of protrusions. In an alternative embodiment, the frame element rotation reducing portions are formed into the frame element during manufacture.

The first member rotation reducing portions on the inside wall of the channel of the first connector can extend along a part of the inside surface of the channel of the first connector. The first member rotation reducing portions can each have a top surface, a rear end wall near the back of the channel, and a forward end wall near the opening of the channel. The top surface of the first member rotation reducing portion can be wide. The top surface of the first member rotation reducing portion can be narrow. There can be as few as 6 first member rotation reducing portions, there can be up to 20 first member rotation reducing portions, depending on the width of the top surface of each portion and the number of splines provided on the frame element. Once mated the frame element rotation reducing portions and the first member rotation reducing portions abut one another and substantially prevent rotational movement. There can be one or two (or more) first member rotation reducing portions between each pair of frame element rotation reducing portions.

The channel has an opening through which the insertion portion of the frame element is received. The opening can be defined by a front wall of the channel which can be a rim around the front of the first connector member. The front wall at the forward part of the first connector can have a smooth flat surface which in some embodiments can be for engagement with the first surface of the protrusion or series of protrusions. In some embodiments, the front wall of the first connector comprises the forward end walls of any rotation reducing portions provided in the channel. Therefore, the front wall can be the rim around the front of the first connector; the forward end walls of any rotation reducing portions provided in the channel; or both provided together. Upon insertion of the frame element into the opening, the protrusion or series of protrusions can abut against the front wall and or the forward wall of the rotation reducing portions which thereby provide a natural stop for further insertion movement of the frame element into the channel. In embodiments, the front wall and or the forward walls of the rotation reducing portions can be modified so as to dovetail with the protrusion(s), so as to further prevent any rotational movement of the frame element once inserted. The front wall of first connector can also dovetail with the second connector in some embodiments.

In some embodiments, the front wall can be modified with at least one gripper. Each of the grippers can be configured to engage with the protrusion(s). When sliding into the channel, the protrusion(s) can slide under finger like grippers extending from the front wall which engage over the protrusion(s) and grip by them. The grippers prevent the frame element from being unwantedly withdrawn from the first connector in use. In embodiments in which there is a gripper, the first side of the protrusion or series of protrusions contacts the front wall of the first connector member by engagement of the grippers with the protrusion(s). The rod or tube is thereby prevented from further insertion movement into the channel.

The channel also has a rear wall, and in this embodiment, the first end of the frame element may or may not abut the rear wall prior to the direct contact between the first surface of the protrusion or series of protrusions, and the front wall of the first connector member. The rear wall can be a solid wall at the rear of the channel. The rear wall can be a partial wall or barrier at the rear of the channel. In some embodiments, upon insertion of the insertion portion of the frame element into the channel, the first end of the frame element abuts the rear wall of the channel before the protrusion or series of protrusions contact with the front wall. In some embodiments, the protrusion or protrusions will never contact the front wall and the only stop is the barrier at the rear wall. In embodiments, therefore, the rear wall provides a natural stop for further insertion movement of the frame element. In this embodiment, if there are protrusions, there may be a gap between the front wall and the protrusion or series of protrusions. In embodiments, the rear wall can be modified so as to interlock with the first end of the insertion portion of the frame element, so as to further prevent any rotational movement of the frame element once inserted. The interlocking can be by a lock and key type of complementary shaping applied to the respective contacting surfaces.

In order to complete the connector, the second connector member is brought into contact with the first connector member. The act of bringing the two members (first connector member and second connector member) into contact can comprise bringing either one of them towards the other. However, in practice, since the frame element is typically already inserted into the first connector member, the act of bringing the second connector member into contact with the first connector member comprises brining the second connector member to the first connector member.

In an embodiment, the second connector member is in two or more parts and it is assembled around the first connector member. The second connector member can be in parts that are hingedly (or otherwise) connected to one another and which can be clamped around the first connector member and then locked into position. The second connector member can have an open position which can receive the first connector member and a closed, locked position in which the second connector member is locked around the first connector member. To lock the second connector member that comes in a plurality of parts into place around the first connector member, there can be a locking mechanism that comprises screws, hook and tab or other.

In an embodiment, the second connector comprises two half-parts a first half-part and a second half-part which can be different from one another or identical to one another. If the two half-parts are identical, once the second half-part is inverted with respect to the first half part, the two half-parts together provide a collar. Each half part can have first joining side and a second joining side. A catch can be provided at the first joining side, the catch can provide a recess. A boss can be provided at the second joining side, the boss can be locatable into the recess of the catch. When the two half-parts are brought together, the respective catches can locate the respective bosses and the two half parts are held securely together around the first connector member. A tool may be required to separate the parts once connected. In an alternative embodiment, the two half parts are not identical. This can be advantageous for making sure that the two half parts are connected in the correct way. Where the two half-parts are identical, there is a chance that one is connected to the other upside down. With two different parts, manufacturing costs might increase but ease of assembly is decreased.

Once in place, in an embodiment, the second connector member can provide a barrier wall that abuts the second side of the protrusion or series of protrusions. The barrier wall thereby prevents any removing movement of the frame element from the channel of the first connector member. The barrier wall can be provided as one continuous wall covering the second side of the protrusion or series of protrusions. The barrier wall could also be provided in separate wall parts provided that the protrusion or series of protrusions abut against it and their movement is barred. In another embodiment, protrusion(s) inside the channel locate into indentation(s) on the frame element and prevent the removal of the frame element from the first connector. In this embodiment, the second connector member provides additional structural integrity to the connector member, reducing any tendency for the frame element to move when pressure it applied in use.

In an embodiment, the second connector member is in one part. When the second connector member is in one part, it is necessary that it has a passageway therethrough to receive the frame element. The second connector member can be passed over the frame element and brought towards the insertion portion inside the channel of the first connector member. Once in place around the first connector member, the second connector member may provide a barrier wall that abuts the second side of the protrusion or series of protrusions. The protrusion(s) may be as described herein integral with the insertion portion. Alternatively, the protrusion(s) may be provided by a washer that slides over the insertion portion. The barrier wall thereby prevents any removing movement of the frame element from the channel of the first connector member.

In an embodiment, the second connector member is in two parts. A barrier wall can be provided on each of the second connector member parts e.g. first and second half-parts. An advantage of the second connector member being in parts which are assembled around the first connector member is that the second connector member can be narrower in diameter. Without the need to slide over the frame element, the second connector member can be made thinner and more streamlined with the first connector member. This can be more aesthetically pleasing and improves functionality under circumstances where the bulkiness of the connector would be disadvantageous. In some embodiments, in which the frame elements are for playground equipment, having a narrow connection point with flush connectors can be useful where there are parts of the equipment that slide over each other (e.g. in a flying fox). Furthermore, any locking latches and bosses as described are preferably as streamlined as possible for aesthetics and safety in use.

The second connector member comprises a connection assembly. The connection assembly can be associated with the barrier wall. The connection assembly is configured to engage the second connector member to the first connector member. The function of the connection assembly is to prevent unintentional disengagement of the second connection member from the first connection member. This can prevent unintentional disengagement of the barrier wall from the second side of the protrusion or series of protrusions, which would be disadvantageous in embodiments in which the barrier wall is holding the whole system together. The connection assembly can be any means that reversibly connects the second connection member to the first connection member.

In an embodiment, the connection assembly is a series of complementary ribs and recess (or protrusions and apertures; or like) on the outside wall of the first connector member and the inside wall of the second connector member that are complementary shapes and which upon engagement cause the first connector member and the second connector member to be interlocked together to prevent disengagement of the second connector member. The connection assembly can also prevent any rotational movement of the second connector member relative to the first connection member when locked into position. The connection assembly can operate together with the locking mechanism on the second connector member to reversibly engage the two members (first connector member and second connector member) to one another.

In an embodiment of the connection assembly, the complementary ribs and recesses on the outside wall of the first connector member and the inside wall of the second connector member come in the form of screw threads. In this embodiment, the second connector member can be screwed onto the first connector member to be interlocked. In an embodiment in which the second connector member is forms in parts, the parts can be assembled and then the assembled second connector member can be screwed onto the first connector member.

As the second connector member is screwed onto the first connector member in a first direction, the barrier wall moves closer to the protrusion or series of protrusions. When the barrier wall abuts the second side of the protrusion or series of protrusions, the second connector member can be given one last tightening turn and then it substantially remains in position. The second connector member can be turned in a second direction that is opposite to the first direction to remove or disengage it from the first connector member. When the second connector member is required to be removed from the first connector member, it can be turned in the second direction until the barrier wall is moved away from the protrusion or series of protrusions and the threads disengage.

In an embodiment, the second connector member is a collar that passes over one or more grippers that have engaged with the protrusion(s). Where each gripper is required to be pulled away from the protrusion(s) to remove the connection, the second connector member can hold them into position and ensure that they are unable to release their gripping forces. In this embodiment, the second connector member comprises a barrier wall itself that once in place causes engagement of the protrusion or series of protrusions by the grippers of the first connector member to remain engaged. In this embodiment, the second connector member can further comprise a connection assembly associated with the barrier wall, i.e. a screw thread or interference fit, that is configured to engage the second connector member to the first connector member. When viewed in cross section, it would be seen that the first connector member (i.e. the grippers thereof) is sandwiched between the protrusion or series of protrusions and the second connector member. The rod or tube thereby cannot be removed from the connection system until the second member is disengaged from the first connector member.

To assist in applying the second connector member to the first connector member in embodiments, the outside wall of the second connector member can be modified with a gripping surface. The gripping surface can include one or more gripping ridges that allow for purchase to be applied to the second connector member to force it into position.

To indicate to the user when the second connector member is in location such that the protrusion or series of protrusions is/are located or sandwiched between the first connector member and the second connector member there can be provided an indicator. The indicator can be a visual indicator. The indicator can be an aural indicator. In an embodiment, the indicator is a click sound that is made when the barrier wall of the second connector member engages with the front wall of the first connector member.

In an embodiment, as the connection assembly is formed by screwing the complementary screw threads to one another, there is an aural indicator of the joining process. This can be provided by at least one ratchet arm provided in the second connector body. The flexible ratchet arm can be biased to a position flush with the second connector body wall, but the ratchet arm can be lifted if a head part of the ratchet arm is forced outwardly from the wall of the second connector. The ratchet arm engages with teeth arranged in formation around the forward peripheral edge of the outside wall of the first connector member. The ratchet arm can be located on the second connector body such that it engages with a tooth of the first connector just prior to the threading process. As the second connector is screwed onto the first connector, the ratchet arm rises over the tooth body and then falls onto the next tooth in series. Advantageously, in embodiments in which there is one row of teeth, the ratchet arm is sized relative to the teeth so that it engages with them over more than one turn. Alternatively, there can be more than one row of teeth in a spiral formation that complements the turning circle of the ratchet arm. Nevertheless, the sequential connection of the ratchet arm with the teeth in the series makes a sound each time the head part of the ratchet arm falls to another tooth. Over a few turns of the second connector relative to the first connector there can be a loud and pleasing mechanical sound that allows the user to at once know that the first and second connectors are bring securely joined, and that the join is as tight as possible since the noise stops. An additional advantage of the ratchet arm, in embodiments, is that once the first connector and the second connector are joined, they are unable to come loose relative to one another because the head part of the ratchet arm may prevent an unscrewing motion. The head part of the ratchet arm can abut the preceding tooth and the bias in the material will not allow rotational movement in the opposite direction. There can be one ratchet arm per half part of the second connector.

In alternative embodiments, the ratchet arm comprises only the head part in the form of a thin fin which depends inwardly from the wall of the first half part or second half part. The thin fin flicks over each of the teeth in the series as the second connector is turned. This sort of ratchet arm will not prevent an undoing movement, but will still provide the aural indicator during tightening.

The number of the teeth and the size of the head part of the ratchet arm will contribute to the loudness and frequency of the aural indicator. In an embodiment in which the diameter of the first connector is about 3.5 cm there are about 32 teeth around the outside periphery of the opening. However, there can be at least about or at most about 10, 20, 30, 40 or 50 or more teeth depending on the size of the first connector. Each tooth can have a slope portion over which the ratchet arm moves in a forward screwing direction and a stop portion. As the head of the ratchet arm falls off the end of the slope portion of a first tooth, the head part of the ratchet arm can fit into the gap defined by the slope portion of a second tooth and the stop portion of the adjacent first tooth. The stop portion of any one tooth prevents rotational movement in the unscrewing direction, since the head of the ratchet arm cannot move past the stop portion in the unscrewing direction. In an embodiment, the slope portion of each tooth and the stop portion of each tooth is the same dimension. This means that each tooth provides for the same tone or pitch of sound as an aural indicator. In an alternative embodiment, the slope portion and the stop portions of each tooth are different angles, lengths and or heights, which makes a different sound (pitch or tone) for each tooth as the ratchet head moves over each different tooth. By varying the teeth and therefore by changing the corresponding sound emitted a tune could be created. The tune could have a simple melody such as Twinkle Twinkle Little Star. This could be extremely pleasing to children helping their parents to assemble play equipment. It is also fun for parents to guess what tune will come next. The sounds could act as a motivator to keep assembling.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

As can be seen inFIG.1, an exemplary frame element10has an elongate body12. The body12in this embodiment is straight. The body of the frame element12has a circular cross section. The elongate body12has a first end14and a second end16. The first end14and the second end16are identical. The first end14of the frame element12can be for joining with the second end16of another, separate frame element10(seeFIG.5). The second end16of the frame element10can be for joining with the first end14of another, separate frame element10(not shown). In some embodiments, each end14,16comprises an insertion portion A as described below. In other embodiments, one end14of the frame element10comprises a first connector member24and the other end16of the frame element16connector comprise an insertion portion A.

The end of the frame element10that will join with the connector20can have an insertion portion A. The insertion portion A is intended for insertion into the body22of the first connector24.

In an embodiment, the insertion portion A can be delimited by one or more protrusions26around the frame element body12. The function of the protrusion(s)26is to provide a part of the frame element10that can be gripped by the first connector24and second connector30members in use. The protrusion(s) around the outside of the frame element body12provide an area of increased diameter or increased cross sectional width for the frame element10.

There can be one circumferential protrusion26as shown inFIG.2A. In the case of a frame element10with a circular cross-section, the protrusion can be an annular ring26. The ring is shown as a solid shape with squared edges. There can be a preference for solid edges to the protrusion26, since the protrusion26will be properly sandwiched between the first connector member24and the second connector member30with all surfaces in contact with other surfaces. Since the function of the protrusion26is to provide an area of increased diameter on the body12of the frame element10, the protrusion26does not have to be a solid ring as shown inFIG.2Aaround the element body12and instead it can be provided in one or more parts as shown inFIG.2B. Where the protrusions26are provided in parts, it can be referred to as a series of protrusions26around the outside periphery of the frame element10. The series of protrusions26can be of any shape such as knobs, squared, rectangular columns, other. InFIG.2Bthere are shown eight protrusions. InFIG.39, each protrusion is the front end of a longitudinal spline.

The protrusions26can be provided on the frame element10. In this embodiment, the frame element10is manufactured with the protrusion(s)26as shown inFIG.2. Thus, the protrusions26are integral with the frame element10and cannot be removed from the frame element10. Alternatively, the protrusions26are provided on an element that is attachable to the frame element10. For example, the end14,16of the frame element10could be capped with a sleeve32that has a part of it comprising one or more protrusions26around its outside periphery. The frame element10can be slid into the sleeve32and can be held by tight interference fit. To assist in gripping the frame element10into the sleeve32there can be a complementary shaped annular recess34for receiving the annular end wall14,16of the frame element10therein (FIG.9). InFIG.9, the sleeve32is shown inserted into the first connector member24, but the frame element10has been removed to show what the sleeve32looks like on the inside. In use, there would be a frame element in the sleeve32. In some embodiments, sleeve32is screwed or otherwise affixed to frame element10as shown in e.g.FIG.13.

Upon insertion of the insertion portion A of the frame element10into the connector20, the first side36the protrusion26is facing forward towards the first connector24. The second side38of the protrusion26is thus facing outwardly once the frame element10is engaged with the first connector24.

The connector20comprises a first connector member24operable with a second connector member30. Embodiments of a part of the connector20are shown inFIG.3andFIG.4. InFIG.3, the connector part has a body22with a first connector member24at one side and a first connector part24at the other side for joining two frame elements10.

Each first connector member24comprises an outside surface40which is accessible and manipulatable. The first connector member has an inside surface42which is the wall defining the interior of a channel44. The channel44in the first connector24is configured to allow insertion of the insertion portion A of the frame element10. The channel44can be slightly wider than the insertion portion A of the frame element10to ensure that it can fit therein. In a preferred embodiment, the channel44is about the same diameter as the frame element10so as to allow a tight interference fit.

Once inserted into the channel44, the frame element10may be able to rotate in the channel. In order to prevent or at least reduce any unwanted rotation, the inside surface wall42of the channel44can be modified with rotation reducing portions46to engage the frame element10. The rotation reducing portions46can be ribs48in the channel wall42that are received into complementary recesses50′ provided on the frame element10. As can be seen inFIG.8, the ribs48and recesses50are arranged circumferentially around inside wall42of the channel44of the first connector member24. The frame element10would thus be prevented from rotating in the channel44since the ribs would not allow for rotational movement.FIG.1shows the complementary shaped rotation reducing portions46provided on a sleeve32. The complementary shaped ribs48′ and recesses50′ slide over one another to prevent rotation. It should be understood that any shaping of the inside wall42of the channel and the frame element10(or associated sleeve32) could be provided.

The channel44has an opening52through which the insertion portion A of the frame element10is received. The opening52can be defined by a front wall54of the channel44which can be a rim around the front of the first connector member24. The front wall54at the forward part of the first connector member24can have a smooth flat surface which in some embodiments can be for engagement with the first surface36of the protrusion26or series of protrusions26.

Upon insertion of the frame element10into the channel44, the protrusion26or series of protrusions26can abut against the front wall54as shown in e.g.FIG.5Aproviding a natural stop for further insertion movement of the frame element10into the channel44. In embodiments, the front wall54can be modified so as to dovetail with the protrusion26which has a complementary shape to interlock with the front wall54(e.g.FIG.13). This interlocking of the protrusion26and front wall54can prevent any rotational movement of the frame element10once inserted into channel44of the first connector24. The channel44also have a rear wall56. The first end14of the frame element10may or may not abut the rear wall56prior to the direct contact between the first36surface of the protrusions26or series of protrusions26, and the front wall54of the first connector member24. In embodiments, the rear wall56can be modified so as to interlock with the first end14of the insertion portion of the frame element10, so as to further prevent any rotational movement of the frame element10once inserted. The interlocking can be by a lock and key type of complementary shaping which inFIG.14is shown as a star-shaped key56which sits into a complementary shaped lock on the first end14of frame element10(not shown). The lock and key can be reversed such that the lock part is on the rear wall while the key is provided on the frame element. The contact of the complementary shapes being received in lock and key arrangement can prevent rotation of the frame element10in channel44.

The rear wall56can be a solid wall at the rear of the channel44. The rear wall can be an annular wall56. The rear wall56need only be sufficient to stop advancement of the frame element10through the channel44of the first connector24. The rear wall56is shown inFIG.8as a barrier at the rear of the channel44. In some embodiments, upon insertion of the insertion portion A of the frame element10into the channel44, the first end14of the frame element10abuts the rear wall56of the channel44before the protrusion26or series of protrusions26contact with the front wall54. In this embodiment, the rear wall56provides a natural stop for further insertion movement of the frame element10. This is shown in e.g.FIG.5B. In this embodiment, there will be a gap G between the front wall54and the protrusion26or series of protrusions26. The gap G will eventually be covered by the second connector member30and should not affect the overall structural integrity of the connector system.FIG.41also shows that an embodiment in which the rear wall456provides a stop for the advancing frame element410. In this embodiment, the protrusion will never prevent advancing movement into the channel444and instead the rear wall456is required as the stop.

In order to complete the connector20, the second connector member30is brought into contact with the first connector member24. InFIG.7BandFIG.7Cthe direction of the movement of the second connector member30is shown by arrows. In an embodiment, the forward wall of the second connector member30can interlock with wall19of the first connector member24. This is also shown inFIG.46.

FIG.10shows a variety of second connector members30. In an embodiment, as shown inFIG.11, the second connector member30is in two or more parts31and33and it is assembled around the first connector member24. The second connector member30can be in parts that are hingedly (or otherwise) connected to one another and which can be clamped around the first connector member24and then locked into position. The second connector member30can have an open position as shown inFIG.11Awhich can receive the first connector member24; and a closed, locked position as shown inFIG.11Bin which the second connector member30is locked around the first connector member24.

To lock the second connector member30that comes in a plurality of parts into place around the first connector member24, there can be a locking mechanism60. The locking mechanism can comprise screws, hook and tab or other. Once in place, the second connector member30provides a barrier wall62that abuts the second side38of the circumferential protrusion26or series of protrusions26. The barrier wall62thereby prevents any removing movement of the frame element10from the channel44of the first connector member24. The barrier wall62can be provided as one continuous wall covering the second side38of the circumferential protrusion26or series of protrusions26. The barrier wall could also be provided in separate wall parts. provided that the circumferential protrusion26or series of protrusions26abut against it and their movement is barred.

In an embodiment, the second connector member30is in one part as shown inFIG.10. When the second connector member30is in one part, it is necessary that it has a passageway64therethrough to receive the frame element10. The second connector member30can be slid over the frame element10and brought towards the insertion portion A inside the channel44of the first connector member24. Once in place around the first connector member24, the second connector member30provides a barrier wall62that abuts the second side38of the circumferential protrusion26or series of protrusions26. The barrier wall62thereby prevents any removing movement of the frame element10from the channel44of the first connector member24.

The second connection member30comprises a connection assembly70associated with the barrier wall62that is configured to engage the second connector member30to the first connector24member so that the barrier wall62is able to act as a barrier. The function of the connection assembly70is to prevent unintentional disengagement of the barrier wall62from the first connector24. The connection assembly70can be any means that reversibly connects the second connection member30to the first connection member24. In an embodiment, the connection assembly70is a series of complementary ribs and recess (or protrusions and apertures; or like) on the outside wall40of the first connector member24and the inside wall72of the second connector member30that are complementary shapes and which upon engagement cause the first connector member24and the second connector member30to be interlocked together to prevent disengagement of the second connector member30.FIG.12shows the arrangement with ribs74and recesses76on outside wall40. The complementary shaped ribs74′ and recesses76′ on inside wall72of the second connector member30cannot be seen.

The connection assembly70as shown can also prevent any rotational movement of the second connector member30relative to the first connection member24when locked into position. The connection assembly70can operate together with the locking mechanism60on the second connector member30to reversibly engage the first connector member24and second connector member30to one another.

In an embodiment, complementary ribs74and recesses76on the outside wall of40the first connector member24and the inside wall72of the second connector member30forming the connection assembly70come in the form of screw threads. In this embodiment, as shown in the Figures the second connector member30can be screwed onto the first connector member24to be interlocked.

As the second connector member is screwed onto the first connector member24in a first direction (seeFIG.7), the barrier wall62moves closer to the circumferential protrusion26or series of protrusions26. When the barrier wall62abuts the second side38of the protrusion26or series of protrusions26(or the first end14of the frame element10hits rear wall56of channel44), the second connector member30can be given one last tightening turn and then it substantially remains in position. The second connector member30can be turned in a second direction that is opposite to the first direction to remove or disengage it from the first connector member24. When the second connector member30is required to be removed from the first connector member24, it can be turned in the second direction until the barrier wall62is moved away from the circumferential protrusion26or series of protrusions and the threads disengage26.

To assist in applying the second connector member30to the first connector member24in embodiments, the outside wall73of the second connector member can be modified with a gripping surface78(FIG.10). The gripping surface can include one or more gripping ridges78that allow for purchase to be applied to the second connector member30to force it into position.

To indicate to the user when the second connector member30is in location such that the protrusion26or series of protrusions26is/are sandwiched between the first connector member24and the second connector member30there can be provided an indicator80. In an embodiment, the indicator80is a click sound that is made when the barrier wall62of the second connector member30engages with the front wall54of the first connector member24. InFIG.13, the indicator80is shown as protrusions82which click with recesses84on the protrusion26.FIG.46shows lower profile protrusions that connect with complementary shaped indentations.

FIG.6is a right-angled connector which allows the connection of frame elements at right angles to one another. Any variation of angle can be accommodated by modification of the connector. A passageway P is also provided through the connector which allows for a further frame element to be joined to the connected frame elements.FIG.7is a three-way connector which allows for the joining of three frame elements into each of the channels44of the connector.FIG.21shows the connector100in place joining the frame elements10of a trampoline.

In an embodiment, the insertion portion A of the frame element10has an indentation80on the frame element body12. The function of the indentation80is to provide a part of the frame element that can be gripped by the first connector24in use. As insertion portion A slides into the channel44of first connector24(as shown inFIGS.15and16), protrusion82provided on the side wall of channel44. The user grips protrusion mover84which comprises a spring-loaded pin biased towards the protracted or engaged position as shown inFIG.15. Upon pulling the pin upwards against the bias pressure, the protrusion82is removable from the channel space and into the wall of the first connector24. In this retracted position, there is room for the frame element10to be inserted. When the user relieves the pressure on protrusion mover84, and the protrusion82is released back into the channel, the protrusion82is aligned with indentation80. The protrusion82engages with the indentation80and thereby prevents unwanted removal of the frame element10from the channel44. For additional structural stability in use, a second connector30can then be located over the first connector element24in the same way as described above. As can be seen inFIG.16, the connection assembly70allowing the first connection element24and second connection element30to mate can be screw threads.

FIGS.17A and17Bshow an alternative embodiment in which the protrusion80is an annulus82movable out from the channel44of the first connector by application of pressure onto protrusion mover84. When the user applies pressure to protrusion mover84as shown inFIG.17A, the insertion portion A of frame element10can be pushed all the way into the channel44until the first end14of the frame element10engages with the rear wall56. As can be seen inFIG.17A, the rear wall is modified with a star-shaped key56which sits into a complementary shaped lock56′ on the first end14of frame element10(seeFIG.18). As can be seen inFIG.19, as the frame element10is inserted into the first connector24, second connector30can be moved into position.

In the embodiment shown inFIG.20, there is shown an embodiment in which the protrusion82is also spring biased; however, in this embodiment, rather than the protrusion82being spring biased into the channel44of the first connector member, the protrusion82is spring biased out of the channel44. As sleeve84is manually moved in the direction of the arrow shown inFIG.20, the protrusion82is able to relax and extend into the wider aperture85of the sleeve84. In this retracted position, the frame element10can be inserted. Once inserted, the sleeve84retraction can be released, and the sleeve84forces protrusion82into the indention80which aligns with it in the channel. There is no second connector30in this embodiment, although one could be used if desired.

In an embodiment, frame element110has an elongate body112. The end of the frame element110that will join with the connector120can have an insertion portion A. The insertion portion A is intended for insertion into the body120of the first connector144. As shown inFIG.23, the channel144inside the first connector120can be provided by an insert121that slides into a tube D to form the first connector120. To join the insert121with the tube D and prevent unwanted movement of it out of the tube D during use, the tube D and connector insert121can be crimped together or otherwise fastened (not shown).

In some embodiments, where the connector is for a tube to tube in a longitudinal line, the front wall154of the connector120can be modified with at least one gripper190. There can be any number of grippers190arranged around the circumference of the front wall154. In an embodiment there are eight grippers190(only four can be seen inFIG.23). A plurality of narrow grippers190can provide improved flexibility over fewer wider grippers190. Each of the grippers190can be configured to engage with the protrusion126provided on the frame element110. When sliding into the channel144, the protrusions126can slide under the finger like grippers190which will engage and grip the protrusion. Once grippers190are locked over the protrusion126, it should be understood that removal of the frame element110from the channel144of the first connector120would be difficult unless each of the gripper190fingers is lifted off the protrusion136to release it. Effectively, the grippers190prevent the frame element110from being unwantedly withdrawn from the first connector120.

In this embodiment ofFIG.23, the second connector member130is a collar that can be passed over the grippers that have engaged with the protrusion126. The second connector member130thereby ensures that the grippers190are held into the gripped position and ensure that the grippers190are unable to release their gripping forces. The collar130can be held in place by frictional forces or other locking mechanism. To release the connector system, the collar130can be disengaged, the grippers190can be released from protrusions126(manually or using tools) and then the frame element110can be withdrawn from connector120.

FIG.24shows an embodiment in which the frame element210that will join with the connector220has an insertion portion A. The insertion portion A is intended for insertion into the body220of the first connector244. Once inserted, the second connector member230can be locked into position by engagement of the connection assembly being a quarter turn screw thread253with complementary features on the inside surface of second connector member230and outside wall of connector244. In order to further prevent unintended removal of the second connector member230once in position, there can be tabs255which snap into the second connector member230. These tabs can function as protrusions226. The tabs255can be sandwiched between the first connector member and the second connector member, wherein the rod or tube210cannot be removed from the connection system until the second member230is disengaged from the first connector member220.

In another embodiment, insertion portion A is received in first connector424and then collar430is secured around the joined frame elements410,410′ with protrusion426sandwiched between them. A turn of the second connector430will secured it in place (FIG.37). InFIG.38there is shown another embodiment in which a clip599can be pressed over second connector530to secure it into place.

Turning now toFIG.25, there is shown a frame element310with a body312. The end of the frame element310that will join with the connector can have an insertion portion A. The insertion portion A is intended for insertion into the body of the first connector324. The insertion portion A can be integral with the body312. The insertion portion A can have a smaller diameter to the remainder of the elongate body312of the frame element. This can be useful where the insertion portion slides into the first connector member and is secured into position by a second connector member where the outside surfaces of the elongate body of the frame element and second connector member can be substantially flush with one another as shown in e.g.FIG.36.

InFIG.25, it can be seen that there is one circumferential protrusion326. The protrusion326is accompanied by longitudinal splines348that extend along the longitudinal length of the insertion portion A. These splines348can assist with decreasing rotation of the frame element310once inserted into the first connector324, if there are complementary ribs inside the channel344of the first connector324.

An embodiment in which there are a plurality of longitudinal splines448around the outside periphery of the insertion portion A is shown inFIG.39. Each spline448is shown formed in one single piece. The spline448is formed across about 85% of the distance of the insertion portion A with a land where the barrier wall462will eventually be located. Each spline448is shown having an elongate axis substantially aligned with the longitudinal axis of the frame element.

Also shown inFIG.39is that the end of insertion portion A can be capped with a capping button427.

There are eight splines448provided around the periphery of the insertion portion A. Each spline has a first longitudinal side448′ and a second longitudinal side448″. Each spline has a forward end436. When the insertion portion A of the frame element410is inserted into the first connector member424the spline448can slide into a channel formed in the inside surface of the first connector member424. Each channel in the first connector member can be formed from longitudinal ribs446. Each rib446can have a first side and a second side. The first side of the rib446can abut with the first longitudinal side of a spline448and the two are unable to pass over one another. This means that rotational forces applied to the frame element410are absorbed by the splines448and ribs446and the frame element410is prevented or substantially reduced from rotating inside the first connector member424.

Turning back toFIG.25, the diameter of the frame element is about 3.5 cm (measured from outside wall to outside wall). The diameter of the frame element (measured from outside edge of protrusion326to outside edge of protrusion326) is increased to about 3.9 cm by the protrusions (about 10%).

As shown inFIG.26, the protrusion326comprises a first side336and a second opposing side338. Upon insertion of the insertion portion A of the frame element310into the connector324, the first side336of the protrusions326is facing forward towards the first connector324. The second side338of the protrusions326is thus facing outwardly once the frame element310is engaged with the first connector324.

The connector320of the present invention comprises a first connector member324operable with a second connector member330. The first connector member324comprises an outside surface. The first connector member has an inside surface which is the wall defining the interior of a channel344.

The channel344in the first connector324is configured to allow insertion of the insertion portion A of the frame element310. The channel344can be slightly wider than the insertion portion A of the frame element310to ensure that it can fit therein. In a preferred embodiment, the channel344is about the same diameter as the frame element310so as to allow a tight interference fit. Once inserted into the channel344, the frame element310, may be able to rotate in the channel. In order to prevent or at least reduce any unwanted rotation, the inside surface of the channel344is modified with rotation reducing portions346to engage the frame element310. As seen inFIG.27, the rotation reducing portions346can be ribs348in the channel wall that are received into complementary recesses350provided on the frame element310. The frame element310would thus be prevented from rotating in the channel344since the ribs348would not allow for rotational movement.

The rotation reducing portions346,348on the inside wall of the channel344of the first connector324can each have a top surface347, a rear end wall (not seen) near the back of the channel344, and a forward end wall349near the opening352of the channel344. The top surface347of the first connector rotation reducing portion346can be narrow as shown inFIG.27. There are about sixteen first connector rotation reducing portions346inFIG.27. The space between each first member rotation reducing portion (or between pairs of them) can be referred to as a channel351.

The channel344has an opening352through which the insertion portion A of the frame element310is received. The opening352can be defined by a front wall354of the channel344which can be a rim354around the front of the first connector member324. The front wall354at the forward part of the first connector324can have a smooth flat surface which in some embodiments can be for engagement with the first surface336of the protrusion326. In some embodiments, the front wall354of the first connector324comprises the forward end walls349of any rotation reducing portions346provided in the channel344. Therefore, the front wall354can be the rim354around the front of the first connector324; the forward end walls349of any rotation reducing portions346provided in the channel344; or both provided together354,349. Upon insertion of the frame element310into the opening352, the protrusion326can abut against the forward walls349of the rotation reducing portions as shown inFIG.29. The protrusion326thereby provides a natural stop for further insertion movement of the frame element310into the channel344.

In order to complete the connector320, the second connector member330is brought into contact with the first connector member324. In an embodiment, the second connector member330is in two parts330aand330band it is assembled around the first connector member324. The second connector member330can be in parts that can be clamped around the first connector member324and then locked into position. The second connector member324can have an open position (FIGS.30and31) which can receive the first connector member324and a closed, locked position (FIGS.32,33,34) in which the second connector member330can be locked around the first connector member324(although inFIGS.32-34the second connector member330is shown separate to the first connector member324).

As shown in theFIGS.30-34, the second connector comprises two half-parts330a,330b. First half-part330aand a second half-part330bare identical to one another. Once the second half-part330bis inverted with respect to the first part330a, the two half-parts together provide the second connector member330. Each half part330a,330b, can have first joining side X and a second joining side Y. A catch331can be provided on each half-part at the first joining side X, the catches331aand331bcan provide a recess (shown as a rectangular hole inFIG.31). A boss333can be provided on each half part at the second joining side Y, the bosses333a,333bcan be locatable into the recesses of the respective catches331a,331b. When the two half-parts330a330bare brought together, the respective catches331a331bcan locate the respective bosses333a333band the two half parts330a330bare held securely together around the first connector member324b. A tool may be required to separate the parts once connected. The tool can be used to prise up the catch331and remove it from the boss333.

In an alternative embodiment, the two half parts430a,430bare not identical as shown inFIG.44. This can be advantageous for making sure that the two half parts are connected in the correct way. As shown in theFIGS.43and44, the second connector can comprise two half-parts430a,430b. First half-part430aand a second half-part430bare different to one another in that430ahas the bosses433and430bhas the catches431a,431b. When the two half-parts430a430bare brought together, the respective catches431a431bcan locate the respective bosses433a433band the two half parts430a430bare held securely together around the first connector member424b. A tool may be required to separate the parts once connected. The tool can be used to prise up the catch431and remove it from the boss433.

Once in place, in an embodiment, the second connector member330can provide a barrier wall362that abuts the second side338of the protrusion326of the insertion portion A. The barrier wall362thereby prevents any removing movement of the frame element310from the channel344of the first connector member324. The barrier wall362is provided in separate wall parts362aand362bas seen inFIG.34. A first barrier wall part362ais on half-part330band a second barrier wall part362bis on provided on half-part330b. The barrier wall462is provided in separate wall parts462aand462bas seen inFIG.44.

The second connector member330comprises a connection assembly370. The connection assembly370is associated with the barrier wall in that it is integral with it. The connection assembly370is configured to engage the second connector member330to the first connector member324. In an embodiment shown the connection assembly370comprises complementary ribs and recesses on the outside wall of the first connector member324and the inside wall of the second connector member330in the form of screw threads. There is a complementary screw thread on the first connector324(seeFIG.27). The function of the connection assembly is to prevent unintentional disengagement of the second connection member330from the first connection member324. As the second connector member330is screwed onto the first connector member324in a first direction, the barrier wall362moves closer to the protrusion326. When the barrier wall362abuts the second side328of the protrusion326, the second connector member330can be given one last tightening turn and then it substantially remains in position. The second connector member330can be turned in a second direction that is opposite to the first direction to remove or disengage it from the first connector member324. When the second connector member330is required to be removed from the first connector member324, it can be turned in the second direction until the barrier wall362is moved away from the protrusion326and the threads disengage.

In an embodiment, as the connection assembly370is formed by screwing the complementary screw threads370,370′ to one another, there is an aural indicator (sound) of the joining process. This can be provided by at least one ratchet arm390provided in the second connector body330. The flexible ratchet arm390is biased to a position flush with the second connector body wall330, but the ratchet arm390can be lifted if a head part392of the ratchet arm390is forced outwardly from the wall of the second connector330. A top view of the ratchet arm390and its head part390can be seen inFIG.35. InFIG.35the insertion portion is removed from the channel344of first connector324so the inside of the mechanism can be seen more clearly. The ratchet arm390engages with teeth394arranged in formation around the forward peripheral edge of the outside wall of the first connector324. The teeth can be seen inFIG.35and quite clearly inFIG.28.

The ratchet arm390is located on the second connector member330body such that it engages with a tooth394of the first connector member324just prior to the threading process. As the second connector member330is screwed onto the first connector324, the ratchet arm390rises over the tooth body394and then falls onto the next tooth394in series. Advantageously, in embodiments in which there is one row of teeth, the ratchet arm390is sized relative to the teeth394so that it engages with them over more than one turn. Alternatively, there can be more than one row of teeth in a spiral formation that complements the turning circle of the ratchet arm390. Nevertheless, the sequential connection of the ratchet arm390with the teeth394in the series makes a sound each time the head part392of the ratchet arm392falls to another tooth394. Over a few turns of the second connector330relative to the first connector324in the direction of the arrows shown inFIG.35there can be a loud and pleasing mechanical sound that allows the user to at once know that the first and second connectors are securely joined, and that the join is as tight as possible since the noise stops. An additional advantage of the ratchet arm390is that once the first connector324and the second connector330are joined, they are unable to come loose relative to one another because the head part392of the ratchet arm390prevents an unscrewing motion. The head part392of the ratchet arm390abuts the preceding tooth394and will not allow rotational movement in the direction opposite to the arrows shown inFIG.35.

The number of the teeth394a,394b,394cand the size of the head part392of the ratchet arm390will contribute to the loudness and frequency of the aural indicator. In an embodiment shown in which the diameter of the first connector324is about 3.5 cm there are about 32 teeth around the outside periphery of the opening. Each tooth394can have a slope portion396over which the head part392of the ratchet arm390moves in a forward screwing direction S. Each tooth394also has a stop portion398. As the head392of the ratchet arm390falls off the end of the slope portion396of a first tooth394a, the head part392of the ratchet arm390can fit into the gap defined by the slope portion396of a second tooth394band the stop portion398of the adjacent first tooth394b(triangular shaped). The stop portion398of any one tooth394prevents rotational movement in the unscrewing direction (opposite to arrow S), since the head392of the ratchet arm390cannot move past the stop portion398in the unscrewing direction. In an embodiment, the slope portion396of each tooth394and the stop portion398of each tooth394is the same dimension as shown inFIG.35. This means that each tooth394provides for the same tone of sound as an aural indicator. In an alternative embodiment, the slope portion396and the stop portions398of each tooth394are different angles, lengths and or heights, which makes a different sound for each tooth as the ratchet head392moves over each different tooth294d,394e,394f. By varying the teeth and therefore by changing the corresponding sound emitted a tune can be created. The three teeth shown inFIG.35will make only three decreasing notes, but it should be understood that with 20 or 30+ teeth over 1, 2 or 3 turning circles a whole melody could be created.

FIG.36shows the second connector330in place with the first connector324with the protrusion (not seen) sandwiched between. Frame element310cannot be removed from the connector320.

The second connector member430also comprises a connection assembly470. In an embodiment, the connection assembly470is formed by screw threads470and470′. To join the first connector424to the second connector430, the user can screw the complementary screw threads474,476to one another, there is an aural indicator (sound) of the joining process. This can be provided by at least one ratchet arm in the form of a thin fin490provided in the second connector body half parts430aand430b. The ratchet arm490engages with teeth494arranged in formation around the forward peripheral edge of the outside wall of the first connector424. The teeth494can be seen inFIGS.40and41.

FIG.45is a cross-sectional view of the connector once assembled. Upon insertion of the insertion portion A of the frame element A into the first connector member424, and mating of the first connector member424with the second connector member430, the frame element410cannot be removed from the first connector member424due to the protrusion426of the frame element410engaging with the second connector member430; and the frame element410is substantially unable to rotate in the first connector member424due to the rotation reducing portions448engaging with the channel44of the first connector member424.

Experimental Testing

Embodiments of the invention will now be described with reference to the following none limiting examples.

The connector of embodiments of the present invention provides more rigidity than prior connectors. In order to quantify “rigidity”, the following experiment was undertaken.Construct a testing frame capable of fixing a connector and/or frame element with joinInsert test frame element, fixed length at 1000 mm, and secure into first connector as intended.Apply force (n), force to be determined, along the XY plane in direction A.Apply force (n), force to be determined, along the XY plane in direction BMeasure total deflection (d). Deflection (d)=Rigidity

Results

Experiment: Cast Steel Joiner Rigidity (Comparative Testing with Existing Metal Connector)

Test Environment Set Up:

Fixed cast steel joiner housed in testing apparatus48.3 mm×2.0 mm steel tube inserted into joiner100 newton force applied to end of length (l)500 newton force applied to end of length (l)

At resting state in the testing apparatus, the steel tube measured 15 mm from the straight edge (FIG.51). With 100 newtons of force applied along the XY plane, the steel tube shows 42 mm of deflection from the straight edge (FIG.52). With 500 newtons of force applied along the XY plane, the steel tube shows 170 mm of deflection from the straight edge (FIG.53). In conclusion, it is evident that the current cast steel joiner that secures the tube using a grub screw shows a significant amount of deflection from its resting position when both a force of 100 newtons and 500 newtons is applied.

Experiment: Present Connector Simulation

It is prophesised that the present connector will have increased rigidity to the existing metal connector. It is hypothesised that the amount of deflection will be substantially less under the same test circumstances.

Simulated results on the frame element to frame element connection (with the connector joining two frame elements as shown inFIGS.54and55) show that with a force of 500N (50 kg) applied on the XY plane, a predicted deflection of 29 mm from its original state.

Any promises made in the present description should be understood to relate to some embodiments of the invention and are not intended to be promises made about the invention as a whole. Where there are promises that are deemed to apply to all embodiments of the invention, the applicant/patentee reserves the right to later delete them from the description and does not rely on these promises for the acceptance or subsequent grant of a patent in any country.