ANGULARLY ADJUSTABLE COUPLING

Field of the invention

This invention relates to an angularly adjustable coupling of the kind utilised to interconnect tubular components in a manner providing for the components to be selectively releasably latched at different angular positions with respect to each other.

Background of the invention

A particular application of couplings of the kind in question is to prams, strollers or pushers and similar push-along vehicles for transporting babies and young children. These vehicles typically include an inclined inverted U-shaped handle assembly of tubular components. In order to accommodate carers of different heights, and to maximise their comfort when pushing the vehicle and to minimise back strain, it is known to provide an adjustable coupling between the handle assembly and the main frame of the vehicle, at each side of the vehicle. One form of this coupling is a pair of interengaged toothed annular members that may be temporarily disengaged by pressing a push button against a return spring to allow relative rotation of the parts.

These angularly adjustable couplings typically comprise a pair of rotatably linked components each made up of an assembly of plastics mouldings. A problem that has come to light in locations of more extreme climate is sudden structural failure of one of these assemblies, resulting in structural collapse or complete separation of the parts. It has been observed that structural failure primarily occurs at the central part of the assembly at the interengaged toothed annular members. In some cases, this structural collapse of one coupling has given rise to strains and stresses in the other coupling which have caused a simultaneous or near simultaneous failure of the other coupling. The result has been complete separation of the handle assembly from the rest of the vehicle, which can of course have very serious consequences depending upon the location of the vehicle.

It is also desirable in the design of prams, strollers or pushers, to have a uniform appearance - not only for aesthetic value, but also for safety. Where a combination of metal and plastic parts are used, the resultant composite can lack the desired surface smoothness and overall finish.

It is an objective of the present invention to at least reduce the likelihood of complete separation occurring at angularly adjustable couplings of the kind discussed.

Summary of the invention

The invention accordingly provides an angularly adjustable coupling including:

a pair of socket or plug members adapted to engage and be fixed to respective tubular components;

means linking said socket or plug members whereby they are relatively moveable to a plurality of positions having different angular relationships between the tubular components;

wherein said socket or plug members are formed in one or more plastics materials and said coupling further includes an elongate reinforcing means co-moulded within said socket or plug members and arranged to link both the socket or plug members;

whereby, on any structural failure of the socket or plug members or of said linking means, the socket or plug members remain connected together.

Preferably, the linking means includes means to selectively releasably latch said socket or plug members at each of said positions.

Preferably, the elongate reinforcing means includes two or more components moulded within the respective socket or plug members. The socket or plug members, and thereby the elongate reinforcing means, are preferably hingedly connected together at a

hinge point so as to be relatively pivotably adjustable according to the angular relationship between the tubular components.

In a preferred form, the reinforcing means comprises a pair of metal plates, and preferably the socket or plug members are hinged together coaxially with the axis of angular adjustment between the tubular components.

Brief description of the drawings

The invention will be further described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of an angularly adjustable coupling according to an embodiment of the invention, shown joining a pair of tubular frame components; and

Figure 2 is an exploded view of the coupling from another direction and orientation.

Detailed description of the embodiments

The illustrated angularly adjustable coupling 10 is shown in situ for interconnecting respective tubular frame components 12, 14. Typically, these tubular components would be part of the main frame and handle frame respectively of a stroller or pram and there would be respective similar couplings 10 on opposite sides of the stroller or pram.

The principal body members of the coupling are indicated at 20, 30. Each comprises a generally tubular socket part 22, 32 of annular cross-section adapted to engage by receiving the respective tubular components 12, 14, and mutually complementary annular parts 24, 34. Annular parts 24, 34 have opposed internal recesses 25, 35 defined about their cylindrical peripheries by generally V-shaped axially aligned teeth. In Figure 2, only the teeth 36 of annular part 34 are visible. The annular parts 24, 34 are assembled together for rotation on a pivot pin 40 and are normally locked together against rotation by a pinion 50 mounted on a boss 52 in cavities 25, 35.

Pinion 50 is moveable axially on boss 52 between a first position, to which it is biased by helical compression spring 54 and in which pinion teeth 51 engage teeth 36, on both annular parts, and a second position wholly within cavity 35 in which the pinion teeth do not engage the teeth of annular part 24. In this latter position, the body members 20, 30 are mutually rotatable, by hand manipulation, on the axis of pin 40 to adjust the relative angular relationship of tubular components 12, 14. To allow this adjustment, pinion 50 is axially pushed from its latching position by a coaxially moveable hollow push button 60 which is exposed to the exterior of annular part 24. Push button 60 has a lipped annular rim 62 that engages the end face of pinion 50. The lip retains the push button in an opening 64 in annular part 24, in which it is slidably keyed by engagement between a transverse web 28 of annular part 24 and a pair of longitudinal slots 68 in push button 60. Web 28 also fixes pin 40 in position.

In an alternative embodiment, coupling 10 can be reversed such that push button 60 is exposed to the interior of annular part 24. This arrangement makes the push buttons 60 of each coupling thumb-operable while a user is gripping the handle of the stroller or pram.

Body members 20, 30 are formed of plastic and house metal plates 72, 73, co-moulded within the body members 20,30. It will have been noted that the axis of sockets 22, 32 are offset from the transverse pivot axis of pin 40. Correspondingly, the inner ends of plates 72, 73 have curved and upset segments 74, 75 so that as body members 20, 30 overlap, the inner ends of the plates 73, 73 overlap and are pivotably fastened together coaxially with the axis of pin 40 by a secure rivet 76 which passes through both annular parts 24, 34.

Respective ends of sockets 22, 32 have fastener apertures 84, 85 in the opposite sides of the respective sockets 22, 32. When the coupling is assembled in situ, respective single fasteners extend through the socket 22, or 32 and the tubular frame component 12 or 14. It will be noted that the outer ends of plates 72, 73 do not extend to fastener apertures 84, 85 and as such are not directly linked to tubular frame components 12,

It will be seen that the finished assembly comprising sockets 22, 32 and co-moulded plates 72, 73 comprises an elongate reinforcing means 70 arranged so that, when the coupling is fixed to the respective tubular components 12, 14, the elongate reinforcing means 70 links both of the sockets 22, 32. The sockets 22, 32 further link both of the tubular components 12, 14. By forming the elongate reinforcing means 70 within sockets 22, 32, the risk of structural failure at the angular adjustment junction is eliminated. Typically, such structural failures can occur, substantially without warning, for example, when there is a fracture in the plastics moulding or welding arising from embrittlement in a more extreme climatic environment, eg. in a very cold or very hot location. In the application under discussion, i.e. a pram, stroller or other baby or child carrying vehicle, the illustrated arrangement guards against the separation of the handle assembly from the main frame assembly.

It will also be understood that the term "comprises" (or its grammatical variants) as used in this specification is equivalent to the term "includes" and should not be taken as excluding the presence of other elements or features.

It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.