WO2018141785A1

WO2018141785A1 - Stroller

Info

Publication number: WO2018141785A1
Application number: PCT/EP2018/052383
Authority: WO
Inventors: Craig PITT
Original assignee: Pitt Craig
Priority date: 2017-02-01
Filing date: 2018-01-31
Publication date: 2018-08-09
Also published as: GB2560876A; GB201701662D0

Abstract

A stroller (1) comprising a spine (2) having a first spine part (5) supporting a handle (19), and a second spine part (6) supporting wheels (4a, 4b, 4c) on which the stroller (1) stands. The stroller (1) has a spine hinge (7) connecting the first spine part (5) and the second spine part (6) to one another. The stroller (1) is foldable between a folded configuration in which first and second spine parts (5, 6) are rotated around the spine hinge (7) towards one another such that a collapsible seat (3) is collapsed, and an extended configuration in which the first and second spine parts (5, 6) are rotated around the spine hinge (7) away from one another such that the collapsible seat (3) is suspended between the first and second spine parts (5, 6). In the extended configuration, the spine hinge (7) is lockable so as to prevent rotation of the first spine part (5) and the second spine part (6) relative to one another and thereby to secure the stroller (1) in the extended configuration.

Description

STROLLER

Field of the Disclosure This disclosure relates to a stroller for transporting a child. The stroller is foldable so that it may be easily carried and stored when not being used to transport a child.

Background to the Disclosure Strollers are commonly used for transporting toddlers and young children over short distances. They have a seat for accommodating a child and wheels on which the stroller can be pushed by a parent or carer. Strollers afford the parent or carer with increased freedom to travel with a child over distances and for durations that the child would be unable to sustain unaided. However, a stroller can become inconvenient for the parent or carer when the child would prefer to walk or to be carried, or when steps or stairs need to be traversed. In particular, it is difficult to manoeuvre an empty stroller whilst at the same time carrying or holding the hand of the child. Similarly, when travelling by car, bus, train or airplane, or when in the home, a stroller may occupy too much space. For these reasons, most strollers are collapsible so as to be more easily carried and stored.

Various designs of collapsible strollers have been proposed, with the general goal of being sufficiently robust to transport a child but at the same time being small and light weight enough to be conveniently carried and stored when collapsed. Most designs are based around a common formula, which uses many different parts and is often referred to as an "umbrella" design. Although some parts of such strollers can be made from light weight material, the large number of parts means that the strollers still tend to incorporate a significant amount of material overall and remain fairly heavy and cumbersome. This usually means that they can only be carried over short distances at best. These strollers also tend to be complex, which increases manufacturing costs and can cause them to be susceptible to breaking. The complexity can also mean that the strollers do not fold small enough to be stowed in small spaces, such as overhead luggage racks and lockers on trains and airplanes.

The present disclosure seeks to address these problems.

Summary of the Disclosure According to one aspect of the disclosure, there is provided a stroller comprising: a spine having a first spine part and a second spine part, the first spine part supporting a handle and the second spine part supporting wheels on which the stroller stands;

a spine hinge connecting the first spine part and the second spine part to one another such that the first spine part and the second spine part are rotatable relative to one another about the spine hinge;

a collapsible seat extending between the first spine part and the second spine part, wherein the stroller is foldable between a folded configuration in which first and second spine parts are rotated around the spine hinge towards one another such that the collapsible seat is collapsed, and an extended configuration in which the first and second spine parts are rotated around the spine hinge away from one another such that the collapsible seat is suspended between the first and second spine parts; and

an actuator movable between an unlocked position in which it unlocks the spine hinge so as to allow the first spine part and second spine part to rotate relative to one another around the spine hinge and a locked position in which it locks the spine hinge so as to prevent rotation of the first spine part and the second spine part relative to one another around the spine hinge and thereby secures the stroller in the extended configuration.

Provision of a hinged spine to support a collapsible seat helps to minimise the weight of the stroller. It also helps to provide a stroller that has small dimensions when folded. In particular, by providing a hinge that is lockable to secure the stroller in the extended configuration, rather than relying on multiple components, such as various struts and braces, to secure the stroller in the extended configuration, the number of

components of the stroller and the complexity of the design may be reduced. This not only reduces weight, but can also provide the stroller with an elegant and aesthetically pleasing appearance.

The spine hinge may be lockable in the folded configuration. This may improve the portability of the stroller, by ensuring that it does not move into the extended configuration unintentionally, e.g. whilst it is being carried. In another example, the spine hinge is only lockable when the stroller is in the extended configuration. This provides a spine hinge with a simple design.

Optionally, the spine hinge comprises a first sliding surface on the first spine part and a second sliding surface on the second spine part, which first sliding surface and second sliding surface face one another in a direction parallel to an axis about which the first spine part and second spine part rotate around the spine hinge so as to allow rotation of the first spine part and the second spine part relative to one another around the spine hinge when the spine hinge is unlocked. The first and second sliding surfaces may improve the ease with which the first spine part and the second spine part rotate around the spine hinge between the folded configuration and the extended configuration.

Abutment of the first sliding surface and second sliding surface may define a plane, which plane is stationary relative to the axis about which the first and second spine parts rotate around the spine hinge irrespective of relative orientation of the first spine part and second spine part around the spine hinge when the spine hinge is unlocked. This may reduce movement of the first spine part and the second spine part in a lateral direction, e.g. along the axis about which the first and second spine parts rotate around the spine hinge, during rotation of the first spine part and the second spine part around the spine hinge between the folded configuration and the extended configuration.

The spine hinge may comprise a first locking element on the first spine part and a second locking element on the second spine part, which first locking element and second locking element face one another in the direction parallel to the axis about which the first spine part and second spine part rotate around the spine hinge so as to prevent rotation of the first spine part and the second spine part relative to one another around the spine hinge when the spine hinge is locked. The first locking element may comprise at least one protrusion and the second locking element may comprise at least one recess, which at least one protrusion and at least one recess interlock with one another to prevent rotation of the first spine part and the second spine part relative to one another around the spine hinge when the spine hinge is locked.

The actuator may urge at least one of the first locking element and the second locking element towards the other to lock the spine hinge. The actuator may have a head that, when the actuator moves between the unlocked position and the locked position, is displaced in a/the direction parallel to an/the axis about which the first spine part and second spine part rotate relative to one another around the spine hinge.

The spine hinge may comprise a spindle on which the first spine part and the second spine part rotate about the axis, and the head may be mounted on the spindle so that it is displaced by sliding along the spindle when the actuator moves between the unlocked position and the locked position.

The actuator may have a lever for displacing the head as the actuator is moved between the unlocked position and the locked position. The lever may rotate about a fulcrum and the actuator may further comprises a rigid coupling pivotally connected to the head and to the lever, wherein in the unlocked position of the actuator, the lever is oriented such that it is pushed by the rigid coupling in a first direction about the fulcrum as the head is displaced away from the spine hinge,

in a locked position of the actuator, the lever is oriented such that it is pushed by the rigid coupling in a second direction about the fulcrum as the head is displaced away from the spine hinge,

the lever being free to rotate about the fulcrum in the first direction but the actuator having a stop that prevents the lever rotating about the fulcrum in the second direction such that when the lever abuts the stop the head cannot be displaced away from the spine hinge.

Optionally, the stroller has biasing means for biasing the actuator towards the unlocked position.

The stroller may comprise a pair of wheel arms, wherein each wheel arm of the pair is mounted to the second spine part and supports at least one of the wheels on which the stroller stands. Each wheel arm of the pair may be foldable towards the second spine part.

In one example, each wheel arm of the pair is provided with a brace for securing the wheel arm in an unfolded position. Each brace may have an elbow joint that folds to allow the wheel arm to fold towards the second spine part, and which unfolds beyond 180 degrees such that the wheel arm is secured in the unfolded position unless the elbow joint is manipulated so as to be unfolded less than 180 degrees. Each wheel arm may have a recess for accommodating the respective brace when the wheel arm is folded towards the second spine part.

Locking pins may be provided to lock the wheel arms in place. In one example, each wheel arm of the pair comprises a locking pin, which locking pin is arranged to secure the respective wheel arm of the pair in the unfolded position.

Optionally, the first spine part is curved outwardly with respect to where the collapsible seat is located, so as to accommodate the collapsible seat. Typically, the spine is a composite material, such as carbon fibre, or a metal such as a magnesium alloy or aluminium.

The handle may extend laterally from the first spine part. Optionally, the handle is foldable towards the first spine part.

A spreader may be provided, extending laterally from the second spine part.

Optionally, in the folded configuration, the first spine part may rest on the spreader.

The collapsible seat is typically removable from the stroller. It may be attachable to the stroller at a plurality of anchor points. Typically, the collapsible seat is attachable to the first spine part via the handle. Similarly, the collapsible seat is usually attachable to the second spine part via the spreader. In one example, the collapsible seat is attachable to each wheel arm.

Typically, the collapsible seat is fabric or cloth. It may have a support that at least partly defines the shape of the collapsible seat when the stroller is in the extended configuration. The support may comprise first and second foldable elements, which first and second foldable elements extend in a direction between the first spine part and the second spine part and are unfolded when the stroller is in the extended configuration. The support may be taught when the stroller is in the extended configuration. Optionally, the support is a cord, for example of nylon, polyester or ultra-high-molecular-weight polyethylene (UHMWPE).

Specific embodiments are described below, by way of example only, with reference to the accompanying drawings. Brief Description of Drawings

Figure 1 is a perspective view of a stroller according to a first embodiment.

Figure 2 is a side view of the stroller.

Figure 3 is a perspective view of the stroller, shown in a folded configuration and omitting a collapsible seat.

Figure 4 is a side view of the stroller, shown in the folded configuration and omitting the collapsible seat.

Figure 5 is a plan view of the stroller, shown in the folded configuration and omitting the collapsible seat.

Figure 6 is a front view of the stroller, shown in the folded configuration and omitting the collapsible seat.

Figure 7 is a close up perspective view of a spine hinge of the stroller, with an actuator shown in an unlocked position.

Figure 8 is a close up perspective view of the spine hinge, with an actuator shown in a locked position.

Figure 9 is a close up bottom view of the spine hinge, with an actuator shown in the locked position.

Figure 10 is an exploded close up perspective view of the spine hinge.

Figure 1 1 is a perspective view of a first end of a first spine part of the stroller and a first end of a second spine part of the stroller, shown in a disassembled state. Figure 12 is a perspective view of the second spine part of the stroller, with wheels mounted and shown with the stroller in an extended configuration.

Figure 13 is a plan view of the second spine part of the stroller, with wheels mounted and shown with the stroller in an extended configuration.

Figure 14 is an exploded close up perspective view of a left wheel arm of the stroller.

Detailed Description of Preferred Embodiments Referring to Figures 1 to 6, a stroller 1 according to an embodiment of the disclosure has a chassis comprising a spine 2. A collapsible seat 3 is mountable on the spine 2. First, second and third wheels 4a, 4b, 4c on which the stroller 1 stands are also provided on the chassis, again by being mountable on the spine 2. The stroller 1 is three- wheeled in this embodiment, although it will be understood that four wheeled versions are also possible.

The stroller 1 is foldable between an extended configuration, as shown in Figures 1 and 2, and a folded configuration, as shown in Figures 3 to 6. In the extended configuration the stroller 1 is arranged to accommodate a toddler or small child, and is moveable over a surface on which is stands by rolling on the first, second and third wheels 4a, 4b, 4c. In the folded configuration the dimensions of the stroller 1 are reduced so that the stroller 1 can be carried and stored more conveniently than in the extended configuration. In this embodiment, in the folded configuration, the stroller 1 is

approximately 80cm long, 20cm wide and 20cm high, and can be easily carried.

The spine 2 comprises a first spine part 5 and a second spine part 6. The first spine part 5 and the second spine part 6 are connected to one another by a spine hinge 7. The spine hinge 7 connects the first spine part 5 and the second spine part 6 to one another such that the first spine part 5 and second spine part 6 are rotatable relative to one another. More specifically, the first spine part 5 and the second spine part 6 are elongate, and the spine hinge 7 is located at a first end 8 of the first spine part 5 and at a first end 9 of the second spine part 6, so that a second end 10 of the first spine part 5 and a second end 1 1 of the second spine part 6 are rotatable towards and away from one another around the spine hinge 7 as the stroller 1 is folded between the extended configuration and the folded configuration.

In the extended configuration of the stroller 1 , the first spine part 5 and the second spine part 6 are oriented at a first orientation with respect to one another, such that there is an angle of approximately 90 degrees between a first imaginary straight line extending between the first and second ends 8, 10 of the first spine part 5 and a second imaginary straight line extending between the first and second ends 9, 1 1 of the second spine part 6. That is, the first and second spine parts 5, 6 are approximately perpendicular to one another. In the folded configuration of the stroller 1 , the first spine part 5 and the second spine part 6 are oriented at a second orientation with respect to one another, such that there is an angle of approximately 0 degrees between the first imaginary straight line and the second imaginary straight line. That is, the first and second spine parts 5, 6 are approximately parallel to one another.

The spine 2 provides the stroller 1 with rigidity. The first spine part 5 and the second spine part 6 are rigid. Specifically, the first spine part 5 and the second spine part 6 each comprise a single piece of a stiff material. More specifically, in this embodiment, each of the first spine part 5 and the second spine part 6 is die cast magnesium alloy. In other embodiments, each of the first spine part 5 and the second spine part 6 is cast or milled aluminium, or alternatively a composite material, such as carbon fibre.

The shapes of the first spine part 5 and the second spine part 6 are adapted to optimise rigidity whilst minimising weight. Holes 12 are provided in the first spine part 5 and second spine part 6. These holes 12 are through-holes, extending all the way through the first spine part 5 and second spine part 6, in a direction generally parallel to an axis A of the spine hinge 7 around which the first spine part 5 and second spine part 6 rotate. As such, the holes 12 reduce the amount of material present in the first spine part 5 and the second spine part 6. This reduces the weight of the first spine part 5 and the second spine part 6, without significantly reducing their strength and rigidity, particularly in the direction of rotation around the axis A of the spine hinge 7.

The first spine part 5 and second spine part 6 also have a cross section that is generally I shaped, or more accurately in a form similar to an I beam. In other words, the first spine part 5 and second spine part 6 each comprise a web 13, that is a flat elongate strip, and flanges 14 on each edge of the web 13, that is walls oriented perpendicular to and extending equidistantly either side of the web 13. This shape can help to maximise rigidity, particularly with the web 13 oriented to be in a plane parallel to that in which the first spine part 5 and second spine part 6 rotate, as shown in the illustrated embodiment.

The web 13 of each of the first spine part 5 and second spine part 6 is reinforced. More specifically, the first spine part 5 and the second spine part 6 each have

reinforcement members 15. In this embodiment, the reinforcement members 15 of each of the first spine part 5 and the second spine part 6 are located on the respective web 13 and extend between the respective flanges 14. The reinforcement members 15 are each oriented at an incline relative to a direction along the length of the first spine part 5 and the second spine part 6 respectively. The direction of incline alternates. More specifically, in this embodiment, the reinforcement members 15 zigzag along the length of each of the first spine part 5 and the second spine part 6. Together with the flanges 14, the reinforcement members 15 provide tessellated triangles along the lengths of the first spine part 5 and the second spine part 6. They act to increase the strength and rigidity of the spine 2.

As can be seen most clearly in Figure 5, the first and second spine parts 5, 6 are laterally offset from one another. In other words, they are located at different positions along the axis A of rotation about the spine hinge 7. This allows the first and second spine parts 5, 6 to be located side by side when the stroller 1 is in the folded configuration. In this context, side by side should be understood in the sense of the stroller 1 being in the extended configuration, and oriented for normal use, e.g. stood on a surface ready for use to convey a child and the direction of travel on the wheels 4a, 4b, 4c being considered as forwards and backwards from the point of view of the direction in which the child faces when sat in the collapsible seat 3. In other embodiments, the first and second spine parts 5, 6 may be offset from one another along the axis A of rotation about the spine hinge 7 only at the first ends 8, 9 of the first and second spine parts 5, 6, with the remainder of the first spine part 5 sitting on top of the second spine part 6 in the folded configuration.

The first spine part 5 curves or bows outwardly with respect to where the collapsible seat 3 is located. This improves the strength of the first spine part in a direction in which it rotates about the axis of rotation A and allows the spine 2 to accommodate the collapsible seat 3 more easily when the stroller 1 is in the extended configuration. More specifically, a gap is maintained between the collapsible seat 3 and the first spine part 5, along the length of the first spine part 5, despite the collapsible seat 3 bowing towards the first spine part 5.

In the extended configuration of the stroller 1 , and with the stroller 1 oriented for normal use to convey a child, the first, second and third wheels 4a, 4b, 4c sit on the ground. An imaginary ground plane is defined by the bottom of the periphery of each of the first, second and third wheels 4a, 4b, 4c. The second spine part 6 extends

approximately parallel to this ground plane. In some embodiments, the second spine part 6 is curved or bowed outwardly with respect to where the collapsible seat 3 is located, like the first spine part 5. However, in the illustrated embodiment, the second spine part is straight, except at the first and second ends 9, 1 1 of the second spine part 6. The first end 9 of the second spine part 6 is inclined away from the ground plane, or towards where the collapsible seat 3 is located, e.g. upwards when the stroller 1 is in the extended configuration and oriented for normal use. This helps to maintain a gap between the spine 2 and the collapsible seat 3 when the stroller 2 is in the extended configuration. The second end 9 of the second spine part 6 is inclined towards the ground plane, or away from where the collapsible seat 3 is located, e.g. downwards when the stroller 1 is in the extended configuration and oriented for normal use. The first wheel 4a of the stroller 1 is mounted on the second spine part 6 at the second end 1 1 of the second spine part 6, and the second end 1 1 extending downwardly, e.g. to be lower than the remainder of the second spine part 6, allows the wheel 4a to be of a smaller diameter whilst maintaining ground clearance of the second spine part 6.

With the stroller 1 in the extended configuration, the second end 1 1 of the second spine part 6, and hence the first wheel 4a, is at the front of the stroller 1 , that is the front as considered when the stroller 1 is moving in a direction of normal travel, e.g. in a direction that a child seated in the collapsible seat 3 would normally face. Based on this orientation, the first end 9 of the second spine part 6 is considered to be towards the rear of the stroller 1 , the side of the stroller 1 to the left of a person facing towards the front of the stroller 1 , e.g. to push the stroller 1 along, is considered the left side of the stroller 1 and the side of the stroller 1 to the right of the person is considered the right side of the stroller 1 . So, the first wheel 4a is mounted at the front of the stroller 1 .

The second spine part 6 has a first axle 16a and the first wheel 4a is mounted to the second spine part 6 via the first axle 16a. The axle 16a extends perpendicularly to the length of the second spine part 6 and parallel to the imaginary ground plane mentioned above. This is also parallel to the axis of rotation A of the first and second spine parts 5, 6 about the spine hinge 7. The first wheel 4a rotates on the first axle 16a and this allows the stroller 1 to roll on the first wheel 4a parallel to the length of the second spine part 6, e.g. in a forward and a backward direction based on the orientation described above.

The stroller 1 also has a pair of wheel supports. The wheel supports comprise a left wheel arm 17b mounted on the left side of the stroller 1 and a right wheel arm 17c mounted on the right side of the stroller 1 . Both the left wheel arm 17b and the right wheel arm 17c are mounted to the second spine part 6. The left wheel arm 17b supports the second wheel 4b and the right wheel arm 17c supports the third wheel 4c.

The left wheel arm 17b and right wheel arm 17c are pivotally connected to the second spine part 6 by respective left and right wheel arm hinges 18b, 18c. In the folded configuration of the stroller 1 , the left wheel arm 17b and right wheel arm 17c are rotated about the left wheel arm hinge 18b and right wheel arm hinge 18c respectively, so as to be generally parallel with the second spine part 6. In the extended configuration of the stroller 1 , the left wheel arm 17b and right wheel arm 17c are rotated about the left wheel arm hinge 18b and right wheel arm hinge 18c respectively, so as each to extend at an angle relative to the length of the second spine part 6. In this embodiment, the left wheel arm 17b and right wheel arm 17c extend obliquely relative to the length of the second spine part 6, or more specifically obtusely relative to a front portion of the second spine part 6. More loosely, the left and right wheel arms 17b, 17c can be considered as "swept back" when extended. In other embodiments, the left wheel arm 17b and right wheel arm 17c extend at other angles, e.g. perpendicularly to the length of the second spine part 6.

The left wheel arm 17b has a second axle 16b and the second wheel 4b is mounted to the left wheel arm 17b via the second axle 16b. Likewise, the right wheel arm 17c has a third axle 16c and the third wheel 4c is mounted to the right wheel arm 17c via the third axle 16c. The second and third axles 16b, 16c are at ends of the left and right wheel arms 16b, 16c that are distal to the second spine part 6 when the stroller 1 is in the extended configuration. The second and third axles 16b, 16c are oriented such that, with the stroller 1 in the extended configuration and the left and right wheel arms 17b, 17c rotated about the left and right wheel arm hinges 18b, 18c to extend at the angle relative to the length of the second spine part 6, they are perpendicular to the length of the second spine part 6 and parallel to the imaginary ground plane. That is, the second and third axles 16b, 16c are parallel to each other and to the first axle 16a. The second and third wheels 4b, 4c rotate on the second and third axles 16b, 16c respectively, allowing the stroller 1 to roll on the second and third wheels 4b, 4c parallel to the length of the second spine part 6, e.g. in the forward and backward directions based on the orientation of the stroller 1 described above.

A handle 19 is provided on the spine 2, mounted to the first spine part 5, at the second end 10 of the first spine part 5. The handle 19 is elongate, and mounted to the first spine part 5 so as to extend generally perpendicularly to both the first spine part 5 and the second spine part 6, with the stroller 1 in the extended configuration; that is generally from side to side with respect to the forward and backward directions.

In more detail, in this embodiment, the handle 19 comprises a left handle part 20b extending to the left side of the first spine part 5 and a right handle part 20c extending to the right side of the first spine part 5. The left handle part 20b and right handle part 20c are elongate elements connected to the first spine part 5 via a handle clamp 21 . Anchor points 22 are provided on each of the left handle part 20b and the right handle part 20c, distal to the handle clamp 21 , for supporting the collapsible seat 3. In this embodiment, the anchor points 22 are mushroom shaped projections around which a cord can be secured. In other embodiments different styles of anchor points 22 are provided, such as hooks, rivets or buckles. The left handle part 20b and right handle part 20c are articulated part way along their length. The articulation is such that the left handle part 20b and right handle part 20c are able to fold in a direction away from the collapsible seat 3, but not towards the collapsible seat 3. This is approximately backwards when the stroller 1 is in the extended configuration and oriented for normal use. Specifically, each articulation is in the form of an elbow joint, appropriately oriented so as to allow the left handle part 20b and right handle part 20c to fold away from the collapsible seat 3, but not towards it. In other embodiments, the left and right handle parts 20b, 20c fold in other directions. In particular, arranging the left and right handle parts 20b, 20c to fold towards the collapsible seat 3, and providing locking elements to lock the left and right handle parts 20b, 20c in their unfolded positions to secure the collapsible seat 3 in the extended configuration of the stroller 1 , can allow the stroller 1 to be more compact in the folded configuration.

In the extended configuration of the stroller 1 , the left handle part 20b and the right handle part 20c are unfolded, and provide support for the collapsible seat 3. In the folded configuration of the stroller 1 , the left handle part 20b and right handle part 20c are folded. Although the left handle part 20b and right handle part 20c fold away from the collapsible seat 3, they are able to fold in the folded configuration of the stroller 1 because the collapsible seat 3 is in a collapsed state. The left handle part 20b and right handle part 20c fold towards the first spine part 5, thereby reducing the overall outer dimensions of the stroller 1 in the folded configuration.

The left and right handle parts 20b, 20c also have bar ends 23 located distal to the clamp 21 . The bar ends 23 are elongate elements extending at an angle relative to the lengths of the left and right handle parts 20b, 20c respectively. In this embodiment, the bar ends 23 extend approximately perpendicularly to the left and right handle parts 20b, 20c, but in other embodiments the bar ends 23 extend obliquely relative to the left and right handle parts 20b, 20c. The bar ends 23 have the benefit of making the handle 19 easier to grip and manipulate. They also allow the user to vary their grip on the handle 19 more widely, which can improve comfort.

A spreader 24 is provided on the second spine part 6, at the second end 1 1 of the second spine part 6. The spreader 24 comprises a left spreader part 25b extending to the left of the second spine part 6 and a right spreader part 25c extending to the right of the second spine part 6. The left spreader part 25b and the right spreader part 25c are elongate elements connected to the second spine part 6 via a spreader clamp 26. Anchor points 22 are provided at each end of the spreader 24 distal to the second spine part 6. The anchor points 22 are similar to those provided on the handle 19. The dimensions of the handle 19 and the spreader 24, and the location of the anchor points 22, are such that the anchor points 22 of the handle 19 and the spreader 24 are each at respective corners of an imaginary quadrilateral, which in this embodiment is approximately rectangular, or alternatively an Isosceles trapezoid with its parallel sides being oriented approximately parallel to the length of the handle 19 and the length of the spreader 24. In view of the offset between the first spine part 5 and the second spine part 6 from side to side, the right spreader part 25b is longer than the left spreader part 25c in this embodiment, in order to allow the anchor points 22 to be appropriately located.

The left handle part 20b, right handle part 20c, bar ends 23, left spreader part 25b and right spreader part 25c of the illustrated embodiment are each hollow tubes of magnesium alloy. However, in other embodiments different constructions and materials are used, such as tubes, extrusions or bars of different light weight metal, such as aluminium, or a composite material.

The collapsible seat 3 is attachable to the first spine part 5 and to the second spine part 6 via the handle 19 and the spreader 24. This is achieved by the collapsible seat 3 being attachable to the anchor points 22.

The collapsible seat 3 comprises a sheet 27 suspended at its corners. The collapsible seat 3 has corners that coincide with the anchor points 22 and is generally quadrilateral, similar to the imaginary quadrilateral defined by the anchor points 22 and described above. Fastenings 28 are provided at each of the corners that cooperate with the anchor points 22 to secure the collapsible seat 3 to the first spine part 5 and the second spine part 6. In this embodiment, the fastenings 28 each comprise loops that fit around the anchor points 22.

In this embodiment, the sheet 27 is flexible. More specifically, it is fabric or cloth. A support is provided that, in the extended configuration of the stroller 1 , at least partly defines the shape of the collapsible seat 3. The support comprises a left foldable element 29b and a right foldable element 29c. The left and right foldable elements 29b, 29c extend in a direction between the first spine part 5 and the second spine part 6 and are unfolded when the stroller 1 is in the extended configuration. In more detail, the left foldable element 29b extends along a left edge of the sheet 27 and the right foldable element 29c extends along a right edge of the sheet 27. The fastenings 28 are located at the ends of the left and right foldable elements 29b, 29c. In this embodiment, the left and right foldable elements 29b, 29c are each a cord, for example of nylon, polyester or ultra- high-molecular-weight polyethylene (UHMWPE), such as dyneema; and the fastenings 28 comprises loops of the cord.

In the extended configuration of the stroller 1 , the left and right foldable elements

29a, 29b extend in a direction between the handle 19 and the spreader 24, on the left and right side of the stroller 1 respectively. The left foldable element 29b extends between the left handle part 20b and the left spreader part 25b, and the second foldable element 29c extends between the right handle part 20c and the right spreader part 25c. This causes the sheet 27 of the collapsible seat 3 to be suspended by the left and right foldable elements 29a, 29b, and supported by the first and second spine parts 5, 6. In the folded configuration of the stroller 1 , the left and right foldable elements 29a, 29b fold so as to allow the collapsible seat 3 to collapse.

An additional anchor point 30 is provided on each of the left and right wheel arms 17b, 17c. The additional anchor points 30 are similar to the other anchor points 22. Left and right stays 31 b, 31 c are provided on the collapsible seat 3 in order to help stabilise the collapsible seat 3 when the stroller 1 is in the extended configuration. A left stay 31 b extends from part way along the left foldable element 29b to the additional anchor point 30 of the left wheel arm 17b and a right stay 31 c extends from part way along the right foldable element 29c to the additional anchor point 30 of the right wheel arm 17b. At the end of the left stay 31 b and the end of the right stay 31 c distal to the collapsible seat 3, an additional fastener 32 is provided. The additional fasteners 32 are similar to the other fasteners 28. The left and right stays 31 b, 31 c are cords, similar to the left and right foldable elements 29b, 29c. When the stroller 1 is in the extended configuration, and with the additional fasteners 32 attached to the additional anchor points 30, the left and right stays 31 b, 31 c are under tension and reduce the freedom of the collapsible seat 3 to move, particularly from side to side.

The collapsible seat 3 also has lateral supports. The lateral supports comprise first, second and third battens 33 extending across the collapsible seat 3, e.g. from side to side or between the left side and right sides of the stroller 1 . More specifically, the first, second and third battens 33 extend between the left and right foldable elements 29b, 29c. The first batten 33 is at the top of the collapsible seat 2; that is closest to the handle 19. The second batten 33 is at the bottom of the collapsible seat 33; that is closest to the spreader 24. The third batten 33 is part way, or approximately mid way, between the top and the bottom of the collapsible seat 33, or in other words part way between the handle 19 and the spreader 24. In this embodiment, the left and right stays 31 b, 31 c extend from the collapsible seat 3 at the location of the ends of the third batten 33. This means that the third batten 33 is directly supported by the left and right stays 31 b, 31 c. The third batten 33 also divides the sheet 37 into two portions, a body portion and a foot portion. When a child is accommodated in the collapsible seat 3, the body of the child is positioned in the body portion and the lower legs and feet of the child are positioned in the foot portion. In other embodiments, the collapsible seat has other designs. In particular, there are more or fewer battens 33, or the battens 33 are positioned differently. In one such embodiment, an additional batten 33 is positioned to define the shape of the body portion of the collapsible seat 3.

The stroller 1 has a foot brake 50 that, when activated, prevents the second wheel 4b from rotating and hence the stroller 1 from rolling on the second wheel 4b. In this embodiment, the foot brake 50 comprises a pedal associated with a latch. The second wheel 4b has a cog that is coaxial with and fixed to the second wheel 4b. The pedal can be manipulated to insert the latch into a gap between teeth of the cog to prevent rotation of the cog and hence the second wheel 4b. Of course, in other embodiments the footbrake 50 is of a different type.

The spine hinge 7 is lockable so as to be able to secure the first spine part 5 and second spine part 6 in the first orientation with respect to one another, that is with the stroller 1 in the extended configuration.

Referring to Figures 7 to 1 1 , the spine hinge 7 comprises a first locking element 101 on the first spine part 5 and a second locking element 102 on the second spine part 6. The first and second locking elements 101 , 102 are each annular, centred on the axis of rotation A, and face one another.

The first locking element 101 comprises one or more protrusions 103 facing towards the second locking element 102. The second locking element 102 comprises one or more recesses 104 facing towards the first locking element 101 . The one or more protrusions 103 cooperate with the one or more recesses 104 to prevent rotation of the first spine part 5 relative to the second spine part 6 when the spine hinge 7 is locked. In order to achieve this, the one or more protrusions 103 and the one or more recesses 104 have complementary shapes and each extend over only part of the circumference of the first and second locking elements 101 , 102.

In more detail, in this embodiment, the first locking element 101 comprises four protrusions 103 spaced around its circumference. Between the protrusions 103, the first locking element 101 has recesses 104, meaning that the first locking element 101 has four recesses 104. Similarly, the second locking element 102 comprises four recesses 104. Between the recesses 104, the second locking element 102 has protrusions 103, meaning that the second locking element 102 has four protrusions 103. The protrusions 103 of the first locking element 101 fit into the recesses 104 of the second locking element 102 and the protrusions 103 of the second locking element 102 fit into the recesses 104 of the first locking element 101 . With the protrusions 103 fitted in the recesses 104, the first locking element 101 and the second locking element 102 cannot rotate relative to one another about the axis of rotation A. In this embodiment, in order to prevent rotation of the first locking element 101 relative to the second locking element 102, the protrusions 103 and recesses 104 are arcs of a circle arranged such that, when they interlock, the protrusions 103 of the first locking element 101 and the protrusions 103 of the second locking element 102 form a complete circle, e.g. a continuous 360° arc. Although in the illustrated embodiment the first and second locking elements 101 , 102 each have four protrusions 103 and four recesses 104, it will be appreciated that this in not essential, and the functionality of the first and second locking elements 101 , 102 can be achieved with a different number of protrusions 103 and recesses 104, including just one protrusion 103 on the first locking element 101 and one recess 104 on the second locking element 102.

In this embodiment, the spine hinge 7 is only lockable when the stroller 1 is in the extended configuration. The protrusions 103 and recesses 104 only therefore fit together when the first spine part 5 and second spine part 6 are in the first orientation with respect to one another, e.g. when the first locking element 101 and second locking element 102 are at one corresponding orientation with respect to one another. In order to achieve this, the arrangement of protrusions 103 and recesses 104 of each of the first locking element 101 and the second locking element 102 has only one degree of circular symmetry around the axis of rotation A, e.g. by the protrusions 103 and/or recesses 104 of the first locking element 101 and second locking element 102 respectively extending through different circumferential distances relative to one another. This feature is optional, and in other embodiments, the spine hinge 7 may be lockable with the first spine part 5 and second spine part 6 at other orientations relative to one another, e.g. when the first spine part 5 and second spine part 6 are at the second orientation relative to one another and the stroller 1 is in the folded configuration. This is achieved by the arrangement of protrusions

103 and recesses 104 of each of the first locking element 101 and the second locking element 102 having more than one, e.g. two, degrees of circular symmetry around the axis of rotation A. Indeed, in other embodiments, the first locking element 101 and the second locking element 102 allow the spine hinge 7 to be lockable at several different orientations of the first spine part 5 and second spine part 6 relative to one another, by incorporating several interlocking positions of the protrusions 103 and recesses 104, or even at a continuum of different orientations by omitting the protrusions 103 and recesses

104 altogether and using friction to prevent relative rotation of the first spine part 5 and the second spine part 6.

When the spine hinge 7 is unlocked the first spine part 5 and second spine part 6 rotate relative to one another by the first locking element 101 and the second locking element 102 rotating freely relative to one another. So, when the spine hinge 7 is unlocked, the protrusions 103 and recesses 104 of the first locking element 101 and the second locking element 102 are not interlocked. Moreover, first surfaces 105 of the protrusions 103 of the first locking element 101 , which first surfaces 105 are closest to the second locking element 102, and second surfaces 106 of the protrusions 103 of the second locking element 102, which second surfaces 106 are closest to the first locking element 102, abut and slide over one another to facilitate rotation of the first locking element 101 and the second locking element 102.

In this embodiment, abutment of the first and second surfaces 105, 106 defines a plane perpendicular to the axis of rotation A of the first and second spine parts 5, 6. The protrusions 103 and their respective first and second surfaces 105, 106 are arranged around the axis of rotation A such that at all relative orientations of the first and second locking elements 101 , 102 around the axis of rotation A, except the orientation(s) at which the protrusions 103 and recesses 104 are interlocked, at least a portion of the first and second surfaces 105, 106 abut one another in the plane on each side of the axis of rotation A, at all angles around the axis of rotation A. This means that the first and second locking elements 101 , 102 are able to slide relative to one another as they rotate without being displaced along the axis of rotation A.

An actuator 107 is provided for locking and unlocking the spine hinge 7. The actuator 107 is moveable between an unlocked position in which it unlocks the spine hinge 7 so as to allow the first spine part 5 and second spine part 6 to rotate relative to one another around the axis of rotation A and a locked position in which it locks the spine hinge 7 so as to prevent rotation of the first spine part 5 and the second spine part 6 relative to one another around the axis of rotation A and thereby secures the stroller 1 in the extended configuration.

The spine hinge 7 has a spindle 108 on which the first spine part 5 and second spine part 6 rotate. The spindle 108 fits through spine hinge holes 109 in each of the first spine part 5 and second spine part 6, which spine hinge holes 109 are centred on the axis of rotation A. An outer surface of the spindle 108 cooperates with an inner surface of the spine hinge holes 109 to support the first spine part 5 and second spine part 6 so that they can rotate around the spindle 108 and the axis of rotation A. The spindle 108 has a flange 1 10 at a first end. The flange 1 10 has spine part holes 1 1 1 that align with spindle holes (not shown) of the second spine part 6 to allow spindle bolts 1 12 to be secured in the spine part holes 1 1 1 and the spindle holes to fix the spindle 108 to the second spine part 6 when it is positioned in the spine hinge hole 109 of the second spine part 6. At a second end, the spindle 108 has a lever support 1 13 including a lever hole 1 14 that extends perpendicularly to the axis of rotation A. The actuator 107 comprises a lever 1 15, a head 1 16 and a rigid coupling 1 17. The head 1 16 comprises an urging member 1 18 and a supporting body 1 19. The urging member 1 18 is a circular ring having an internal diameter that allows it to fit onto the spindle 108. The supporting body 1 19 is an arch extending from one side of the urging member 1 18 to the other, across a diameter and out of the plane of the circular ring. The internal dimensions of the arch are sufficient to allow the supporting body 1 19 to fit over the spindle 108. A first rigid coupling hole 120 is provided in the supporting body 1 19, approximately at the apex of the arch. The first rigid coupling hole 120 is located along the main axis of the ring, such that when the head 1 16 is fitted onto the spindle 108, the first rigid coupling hole 120 lies along the axis of rotation A, perpendicular to the axis of rotation A. The head 1 16 is located at the second end of the spindle 108, which is on an opposite side of the spine hinge 7 to the flange 1 10 of the spindle 108, as described in more detail below.

The rigid coupling 1 17 comprises two rods, each having a supporting body hole 121 at a first end and a lever hole 122 a second end; there being two supporting body holes 121 and two lever holes 122 in total. The rigid coupling 1 17 is located between the head 1 16 and the lever 1 15.

The lever 1 15 is generally elongate. It incorporates a gap 123 that accommodates both the supporting body 1 19 of the head 1 16 and the rigid coupling 1 17. The gap 123 is elongate along the length of the lever 1 15, and open at one end of the lever 1 15. So, the gap 123 is effectively a slot. The lever 1 15 also has a lever support hole 124 and a second rigid coupling hole 125. The lever support hole 124 and a second rigid coupling hole 125 extend perpendicularly to the length of the lever 1 15, and are each located on both sides of gap 123. The lever support hole 124 is at the end of the lever 1 15 where the gap 123 is open. The second rigid coupling hole 124 is part way (approximately mid way) along the length of the lever 1 15.

With the spindle 108 located in the spine hinge holes 109 of the first spine part 5 and the second spine part 6, and secured in place by the spindle bolts 1 12 being located in the spine part holes 1 1 1 and the spindle holes, the second end of the spindle 108 and therefore the lever support 1 13 extend out through the spine hinge hole 109 of the first spine part 5 into a cylindrical void 126 provided on the outside of the first spine part 5. The cylindrical void 126 is coaxial with the spine hinge hole 109 of the first spine part 5, but of larger diameter, and is open towards the outside of the first spine part 5.

The head 1 16 is mounted on the second end of the spindle 108, over the lever support 1 13 and inside the cylindrical void 126. More specifically, the urging member 1 18 of the head 1 16 fits in a ring shaped space between an outside surface of the spindle 108 and an inside surface of the cylindrical void 126. Biasing means is provided to urge the head 1 16 away from the first spine part 5 along the axis of rotation A. In this embodiment, the biasing means comprises compression springs 127. Specifically, there are four compression springs 127 distributed evenly around the circumference of the ring shaped space in which the urging member 1 18 of the head 1 16 is located. The first spine part 5 has corresponding biasing means holes 128 for accommodating one end of each of the compression springs 127 to retain them in position.

The lever 1 15 fits over the supporting body 1 19 of the head 1 16, by

accommodating an outer part of the supporting body 1 19 in the gap 123. In this position, the lever 1 15 is attached to the spindle 108. More specifically, a lever bolt 129 fits through the lever support hole 124 of the lever 1 15 and the lever hole 1 14 of the spindle 108 to secure the lever 1 15 in place. The lever bolt 129 cooperates with a lever nut 130 so that it remains securely in position. In this way, the lever 1 15 is secured to the spindle 108 so that the lever 1 15 it can rotate around the lever bolt 129, which provides a fulcrum for the lever 1 15. It will also be appreciated that the lever bolt 129 is positioned in a space defined between the urging member 1 18 and the supporting body 1 19 of the head 1 16. This means that the head 1 16 is loosely retained in position in the cylindrical void 126 by the lever 1 15.

The rigid coupling 1 17 is secured at its first end to the supporting body 1 19 of the head 1 16. More specifically, a first rigid coupling bolt 131 is positioned in the supporting body hole 121 of the rigid coupling 1 17 and the first rigid coupling hole 120 of the supporting body 1 19. The first rigid coupling bolt 131 cooperates with a first rigid coupling nut 132 so that it remains securely in position.

The rigid coupling 1 17 is secured at its second end to the lever 1 15. More specifically, a second rigid coupling bolt 133 is positioned in the lever hole 122 of the rigid coupling 1 17 and the second rigid coupling hole 125 of the lever 1 15. The second rigid coupling bolt 133 cooperates with a second rigid coupling nut 134 so that it remains securely in position.

The actuator 107 has an unlocked position, as shown in Figure 7, and a locked position, as shown in Figures 8 and 9.

In the unlocked position of the actuator 107, the lever 1 15 is rotated about the lever bolt 129 to a first orientation, at which it is inclined to a first side of the axis of rotation A. In this position, as the compression springs 127 urge the head 1 16 away from the first spine part 5, a distance between the lever bolt 129 securing the lever 1 15 to the lever support 1 13 of spindle 108 and the first rigid coupling bolt 131 increases. This causes the rigid coupling 1 17 to urge the lever 1 15 to rotate in a first direction further to the first side of the axis of rotation A, via the second rigid coupling bolt 133. The lever 1 15 is free to rotate in this first direction, therefore allowing the head 1 16 to be displaced away from the first spine part 5 and a distance between the urging member 1 18 of the head 1 16 and the flange 1 10 of the spindle 108 to increase. This in turn allows the first locking element 101 and second locking element 102 of the first spine part 5 and second spine part 102 respectively to move apart from one another, and the spine hinge 7 to be unlocked.

In the locked position of the actuator 107, the lever 1 15 is rotated about the lever bolt 129 to a second orientation, at which it is inclined to a second side of the axis of rotation A, opposite to the first side of the axis of rotation A. In this position, as the compression springs 127 urge the head 1 16 away from the first spine part 5, the distance between the lever bolt 129 securing the lever 1 15 to the lever support 1 13 of spindle 108 and the first rigid coupling bolt 131 cannot increase, because to do so the rigid coupling 1 17 must cause the lever 1 15 to rotate in a second direction further to the second side of the axis of rotation A, via the second rigid coupling bolt 133, but a stop of the lever 1 15 prevents this. As can be seen most clearly in Figure 9, the stop comprises a recess 135 on each side of the gap 123 of the lever 1 15, which recesses 135 are positioned so as to accommodate the first rigid coupling bolt 131 and first rigid coupling nut 132. This means that the first locking element 101 and second locking element 102 of the first spine part 5 and second spine part 102 cannot move apart from one another, and the spine hinge 7 is locked.

The orientation of the lever 1 15 when the first rigid coupling bolt 131 and first rigid coupling nut 132 are accommodated in the recesses 135 is also such that displacement of the head 1 16 by the compression springs 127 cannot translate into movement of the lever 1 15 in the first direction. More specifically, the rigid coupling 1 17 is positioned in this orientation of the lever 1 15 so as to urge the lever 1 15 in the second direction rather than the first direction under the force of the compression springs 127. However, a user can still manipulate the lever 1 15 against the force of the compression springs 127 so that it is oriented on the first side of the axis of rotation A. The lever 1 15 then again becomes free to move in the first direction, thereby allowing the first locking element 101 and the second locking element 102 to move away from one another and the spine hinge 7 to be unlocked.

In this embodiment, in order for the first locking element 101 and the second locking element 102 to move apart from one another, to allow the first spine part 5 and second spine part 6 to rotate relative to one another, a user will usually urge the first locking element 101 away from the second locking element 102 against for exerted by the compression springs 127 between the head 1 16 and the first locking element 101 .

However, in other embodiments, additional biasing means is provided in order to bias the first locking element 101 and the second locking element 102 away from one another. This biasing means can overcome the force of the compression springs 127 when the actuator is in the unlocked position, so that the first locking element 101 and the second locking element 102 move apart without requiring any manipulation by the user. In one such embodiment, the additional biasing means comprises two washers provided between the first locking element 101 and the second locking element 102 with

compression springs between them. The washers have an internal diameter sufficient to fit over the spindle and an outer diameter small enough to be radially inward of the protrusions 103 and recesses 104. The protrusions 103 and recesses 104 may be modified to accommodate the washers.

Referring to Figures 12 to 14, it can be seen that the left and right wheel arm hinges 18b, 18c of the left and right wheel arms 17b, 17c each have a hinge stop 201 b, 201 c facing the second spine part 6 and a hinge pin 202b, 202c. The hinge stops 201 b, 201 c are each positioned at a first edge of an end surface of the respective left and right wheel arms 17b, 17c and the hinge pins 202b, 202c are positioned a second edge of the end surface of the respective left and right wheel arms 17b, 17c. In this embodiment, the first edges at which the hinge stops 201 b, 201 c are positioned are towards the rear of the stroller 1 , with the stroller 1 in the extended configuration and oriented for normal use; that is closest to the spine hinge 7. The second edges at which the hinge pins 202b, 202c are positioned are towards the front of the stroller 1 ; that is, closest to the first wheel 4a.

The left and right wheel arms 17b, 17c rotate around the hinge pins 202b, 202c and the hinge stops 201 b, 201 c rest against a side of the second spine part 6 when the stroller 1 is in the extended configuration. The hinge stops 201 b, 201 c prevent the left and right wheel arms 17b, 17c from rotating beyond the angle at which they are located when the stroller 1 is in the extended configuration. It can be appreciated that the left and right wheel arm hinges 18b, 18s therefore function in the manner of leaf hinges, with one leaf being the hinge stops 201 b, 201 c and the other leaf being the second spine part 6.

In this embodiment, the left and right wheel arms 17b, 17c are mounted at different locations to one another along the length of the second spine part 6 and have different lengths to one another. This allows the second and third wheels 4b, 4c to be located at different positions along the length of the second spine part 6 when the stroller 1 is in the folded configuration, as can be seen most clearly in Figure 5, whilst being located equidistantly on either side of the centre line of the collapsible seat 3 when the stroller 1 is in the extended configuration, as can be seen most clearly in Figure 13. More specifically, in this embodiment, as the second spine part 6 is offset to the left of the centre line of the collapsible seat 3, the left wheel arm 17b is shorter than the right wheel arm 17c. The left wheel arm 17b is also located along the second spine part 6 closer to the spine hinge 7 than the right wheel arm 17c. When the stroller 1 is the folded configuration, this means that the third wheel 4c, which is mounted on the right wheel arm 17c, is located closer to the first wheel 4a at the front of stroller 1 then the second wheel 4b, which is mounted to the left wheel arm 176. As such, the second and third wheels 4b, 4c do not obstruct one another when the stroller 1 is in the folded configuration, and the left and right wheel arms 17b, 17c can fold closer to the second spine part 6, making the stroller 1 more compact in the folded configuration.

The left and right wheel arms 17b, 17c are braced to secure them at the appropriate angle with respect to the second spine part 6 when the stroller 1 is in the extended configuration. More specifically, the left wheel arm 17b has a left brace 203b, and the right wheel arm 17c has a right brace 203c. Each of the left brace 203b and right brace 203c extends between the second spine part 6 and the respective left and right wheel arms 17b, 17c and, when deployed, is able to prevent the respective left and right wheel arms 17b, 17c rotating towards the second spine part 6.

The left and right braces 203b, 203c are mounted to the second spine part 6 by first left and right brace hinges 204b, 204c respectively. They are also mounted to the left and right wheel arms 17b, 17c by second left and right brace hinges 205b, 205c respectively. The first left and right brace hinges 204b, 204c are located on the second spine part 6 between the left and right wheel arm hinges 18b, 18c and the first wheel 4a; that is towards the front of the stroller 1 . As such, whilst the hinge stops 201 b, 201 c prevent the left and right wheel arms 17b, 17c over rotating towards the rear of the stroller 1 , the left and right braces 203b, 203c secure the left and right wheel arms 17b, 17c against rotation towards the front of the stroller 1 , e.g. towards their positions parallel to the second spine part 6 when the stroller 1 is in the folded configuration.

The left brace 203b comprises a first left brace part 206b and a second left brace part 207b connected to one another by a left brace elbow joint 208b. The right brace 203c comprises a first right brace part 206c and a second right brace part 207c connected to one another by a right brace elbow joint 208c. The first left and right brace parts 206b, 206c extend from the first left and right brace hinges 204b, 204c on the second spine part 6 to the left and right elbow joints 208b, 208c respectively. The second left and right brace parts 207b, 207c extend from the second left and right brace hinges 205b, 205c on the left and right wheel arms 17b, 17c to the left and right elbow joints 208b, 208c respectively. The left and right braces 203b, 203c are foldable at the left and right elbow joints 208b, 208c to allow the left and right wheel arms 17b, 17c to rotate towards the second spine part 6. However, when the left and right wheel arms 17b, 17c are rotated away from the second spine part 6 such that the hinge stops 201 b, 201 c rest against the second spine part 6, the left and right braces 203b, 203c unfold so as to be approximately straight; that is with the first and second left brace parts 206b, 207b in line with one another and the first and second right brace parts 206b, 207b in line with one another, as shown in Figures 12 and 13. In this position, the elbow joints 208b, 208c can unfold beyond 180 degrees, or "over rotate/extend", until they are unable to rotate any further. Once the elbow joints 208b, 208c are in this position, should the left or right wheel arms 17b, 17c be urged back towards the second spine part 6, the elbow joints 208b, 208c have a tendency to try to rotate further beyond 180 degrees. As the elbow joints 208b, 208c are unable to fold in this direction, movement of the left and right wheel arms 17b, 17c towards the second spine part 6 is prevented. Only by a user manipulating the elbow joints 208b, 208c such that they are unfolded by less than 180 degrees can the left and right wheel arms 17b, 17c be released to rotate back towards the second spine part 6.

The left and right wheel arms 17b, 17c have respective left and right recesses 209b, 209c for accommodating the left and right braces 203b, 203c when the left and right wheel arms 17b, 17c are folded towards the second spine part 6. The left and right recesses 209b, 209c are in the form of channels extending along the length of the left and right wheel arms 17b, 17c, located in the sides of the left and right wheel arms 17b, 17c facing towards the front of the stroller 1 when the stroller 1 is in the extended configuration and towards the second spine part 6 when the stroller 1 is in the folded configuration. The left and right recesses 209b, 209c accommodate the left and right braces 203b, 203c so as to allow the left and right wheel arms 17b, 17c to fold closer to the second spine 6 part.

In addition to the left and right braces 203b, 203c, the left and right wheel arms 17b, 17c incorporate locking arrangements to further secure the left and right wheel arms 17b, 17c in position when the stroller 1 is in the extended configuration. The locking arrangement of the left wheel arm 17b comprises a left locking holder 210b and a left locking pin 21 1 b positioned to one side of the second left brace hinge 205b. The locking arrangement of the right wheel arm 17c comprises a right locking holder 210c and a right locking pin 21 1 c positioned to one side of the second right brace hinge 205c. With the left and right braces 203b, 203c fully extended, a stub of each of the second left and right brace parts 207b, 207c is pivoted towards the left and right wheel arms 17b, 17c respectively. The left and right locking holders 210b, 210c are located adjacent to a space in which the respective stubs travel as the left and right wheel arms 17b, 17c rotate back towards the second spine part 6. The left and right locking pins 21 1 b, 21 1 c are insertable in the left and right locking holders 210b, 210c respectively to occupy these spaces. The stubs are unable to move with the left and right locking pins 21 1 b, 21 1 c in place, and rotation of the left and right wheel arms 17b, 17c towards the first spine part 3 is thereby prevented unless the left and right locking pins 21 1 b, 21 1 c are removed.

When being used to transport a child, the stroller 1 is arranged in the extended configuration. The child is sat in the collapsible seat 3. A harness (not shown) can be provided to secure the child in the collapsible seat 3. In this configuration, the stroller 1 can be pushed by a parent or carer, so as to convey the child in the stroller 1 .

When desired, the child can be removed from the stroller 1 and the stroller 1 folded to the folded configuration so that it can be carried over the shoulder or across the back, or alternatively can be stored. In order to fold the stroller 1 to the folded

configuration, the user moves the lever 1 15 of the spine hinge 7 from the second orientation to first orientation. In this position, the actuator 1 17 is in the unlocked position, with the head 1 16 being free to move away from the spindle 108. This allows the first locking element 101 and the second locking element 102 to move away from one another, the spine hinge 7 to be unlocked and the first and second spine parts 5, 6 to rotate relative to one another.

Typically, the first spine part 5 is rotated downwardly towards the second spine part 6 until the second end 10 of the first spine part 5 reaches the second end 1 1 of the second spine part 6, and more specifically reaches and rests on the right spreader part 25c, whilst the first, second and third wheels 4a, 4b, 4c of the stroller 1 remain on the ground. The first spine part 5 and the second spine part 6 are therefore close to one another, as shown in Figures 3 to 6. This brings together the handle 19 and the spreader 24, which allows the collapsible seat 3 to fold or collapse.

The left and right handle parts 20b, 20c are then folded towards the second end 10 of the first spine part 5. The user also rotates the first and second wheel arms 17b, 17c towards the second spine part 6. In more detail, the user first removes left and right locking pins 21 1 b, 21 1 c from the left and right locking holders 210b, 210c so that the left and right braces 203b, 203c are free to fold. The user then pushes the left and right elbow joints 208b, 208c of the left and right braces 2003b, 203c, so that the angle of the left and right elbow joints 208b, 208c is less than 180 degrees. This allows the left and right wheel arms 17b, 17c to be rotated towards the second spine part 6.

The stroller 1 is now in the folded configuration. In this configuration, the stroller 1 can be inserted into a bag ready to be carried or stowed. Alternatively, a carry strap can be attached to the first and/or second spine parts 5, 6 to aid carrying of the stroller 1 over the shoulder, across the back or as a backpack. The carry strap may have clips attachable onto the spine 2 at defined locations along the spine 2. Alternatively, the carry strap may comprise extensions that wrap around the spine 2 and secure onto themselves, for example, by Velcro. Carrying the stroller 1 in this way, both hand of the user are left free to attend to the child.

When it is desired to use the stroller 1 for transporting the child again, the user unfolds the stroller 1 to the extended configuration. In order to do this, the user first rotates the left and right wheel arms 17b, 17c away from the second spine part 6. The user ensures that the left and right elbow joints 208b, 208c are unfolded beyond 180 degrees, and that the left and right locking pins 21 1 b, 21 1 c are inserted in the left and right locking holders 210b, 210c. Next, the user unfolds the left and right handle parts 20b, 20c away from the first spine part 5 and proceeds to unfold the spine 2. More specifically, the user rotates the first spine part 5 away from the second spine part 6 and, when the first and second spine parts 5, 6 are oriented in the first orientation, the user manipulates the lever 1 15 so as to move the actuator 107 to the locked position. The stroller 1 is now in the extended configuration and it is ready to be used.

It will be appreciated that other features of strollers, such as wind breakers, parasols, rain covers and the like can be part of the stroller 1 but are left out of the description for the sake of brevity and clarity.

Other variations and modifications will be apparent to the skilled person. Such variations and modifications may involve equivalent and other features which are already known and which may be used instead of, or in addition to, features described herein. Features that are described in the context of separate embodiments may be provided in combination in a single embodiment. Conversely, features which are described in the context of a single embodiment may also be provided separately or in any suitable subcombination.

It should be noted that the term "comprising" does not exclude other elements, the term "a" or "an" does not exclude a plurality, a single feature may fulfil the functions of several features recited in the claims and reference signs in the claims shall not be construed as limiting the scope of the claims. It should also be noted that the Figures are not necessarily to scale; emphasis instead generally being placed upon illustrating the principles of the present disclosure.

Claims

1 . A stroller comprising:

a spine having a first spine part and a second spine part, the first spine part supporting a handle and the second spine part supporting wheels on which the stroller stands;

a collapsible seat extending between the first spine part and the second spine part, wherein the stroller is foldable between a folded configuration in which first spine part and the second spine part are rotated around the spine hinge towards one another such that the collapsible seat is collapsed, and an extended configuration in which the first spine part and the second spine part are rotated around the spine hinge away from one another such that the collapsible seat is suspended between the first spine part and the second spine part to accommodate a child; and

2. The stroller according to claim 1 , wherein the spine hinge is only lockable when the stroller is in the extended configuration.

3. The stroller according to claim 1 or claim 2, wherein the spine hinge comprises a first sliding surface on the first spine part and a second sliding surface on the second spine part, which first sliding surface and second sliding surface face one another in a direction parallel to an axis about which the first spine part and second spine part rotate around the spine hinge so as to allow rotation of the first spine part and the second spine part relative to one another around the spine hinge when the spine hinge is unlocked.

4. The stroller according to claim 3, wherein abutment of the first sliding surface and second sliding surface defines a plane, which plane is stationary relative to the axis about which the first spine part and the second spine part rotate around the spine hinge irrespective of relative orientation of the first spine part and second spine part around the spine hinge when the spine hinge is unlocked.

5. The stroller according to any one of the preceding claims, wherein the spine hinge comprises a first locking element on the first spine part and a second locking element on the second spine part, which first locking element and second locking element face one another in a/the direction parallel to an/the axis about which the first spine part and second spine part rotate around the spine hinge so as to prevent rotation of the first spine part and the second spine part relative to one another around the spine hinge when the spine hinge is locked.

6. The stroller according to claim 5, wherein the first locking element comprises at least one protrusion and the second locking element comprises at least one recess, which at least one protrusion and at least one recess interlock with one another to prevent rotation of the first spine part and the second spine part relative to one another around the spine hinge when the spine hinge is locked.

7. The stroller according to claim 5 or claim 6, wherein the actuator has a head that urges at least one of the first locking element and the second locking element towards the other to lock the spine hinge when the actuator is in the locked position.

8. The stroller according to any one of the preceding claims, wherein, when the actuator moves between the unlocked position and the locked position, a/the head of the actuator is displaced in a/the direction parallel to an/the axis about which the first spine part and second spine part rotate relative to one another around the spine hinge.

9. The stroller according to claim 8, wherein the spine hinge comprises a spindle on which the first spine part and the second spine part rotate about the axis, and wherein the head is mounted on the spindle so that it is displaced by sliding along the spindle when the actuator moves between the unlocked position and the locked position.

10. The stroller according to claim 8 or claim 9, wherein the actuator has a lever for displacing the head as the actuator is moved between the unlocked position and the locked position.

1 1 . The stroller according to claim 10, wherein the lever rotates about a fulcrum and the actuator further comprises a rigid coupling pivotally connected to the head and to the lever, wherein

in the unlocked position of the actuator, the lever is oriented such that it is pushed by the rigid coupling in a first direction about the fulcrum as the head is displaced away from the spine hinge,

12. The stroller according to any one of the preceding claims, comprising biasing means for biasing the actuator towards the unlocked position.

13. The stroller according to any one of the preceding claims, comprising a pair of wheel arms, wherein each wheel arm of the pair is mounted to the second spine part and supports at least one of the wheels on which the stroller stands.

14. The stroller according to claim 13, wherein each wheel arm of the pair is foldable towards the second spine part.

15. The stroller according to claim 13 or claim 14, wherein each wheel arm of the pair is provided with a brace for securing the wheel arm in an unfolded position.

16. The stroller according to claim 15, wherein each brace has an elbow joint that folds to allow the wheel arm to fold towards the second spine part, and which unfolds beyond 180 degrees such that the wheel arm is secured in the unfolded position unless the elbow joint is manipulated so as to be unfolded less than 180 degrees.

17. The stroller according to claim 15 or claim 16, wherein each wheel arm of the pair has a recess for accommodating the respective brace when the wheel arm is folded towards the second spine part.

18. The stroller according to any one of claims 13 to 17, wherein each wheel arm of the pair comprises a locking pin, which locking pin is arranged to secure the respective wheel arm of the pair in the unfolded position.

19. The stroller according to any one of claims 13 to 18, wherein the collapsible seat is arranged to be attachable to each wheel arm of the pair.

20. The stroller according to any one of the preceding claims, wherein the first spine part is curved outwardly with respect to where the collapsible seat is located.

21 . The stroller according to any one of the preceding claims, wherein the collapsible seat is attachable to the first spine part via the handle.

22. The stroller according to any one of the preceding claims, wherein the handle extends laterally from the first spine part.

23. The stroller according to claim 23, wherein the handle is foldable towards the first spine part.

24. The stroller according to any one of the preceding claims, comprising a spreader that extends laterally from the second spine part.

25. The stroller according to claim 25, wherein, in the folded configuration, the first spine part rests on the spreader.

26. The stroller according to claim 24 or claim 25, wherein the collapsible seat is attachable to the second spine part via the spreader.

27. The stroller according to any one of the preceding claims, wherein the collapsible seat has a support that at least partly defines the shape of the collapsible seat when the stroller is in the extended configuration.

28. The stroller according to claim 27, wherein the support comprises a first and second foldable elements, which first and second foldable elements extend in a direction between the first spine part and the second spine part and are unfolded when the stroller is in the extended configuration.

29. The stroller according to claim 27 or claim 28, wherein the support is taught when the stroller is in the extended configuration.

30. The stroller according to any one of claims 27 to 29, wherein the support is a cord, for example of nylon, polyester or Ultra High Molecular Weight PolyEthylene (UHMWPE).

31 . The stroller according to any one of the preceding claims, wherein the collapsible seat is fabric or cloth.

32. The stroller according to any one of the preceding claims, wherein the collapsible seat is removable.

33. The stroller according to any one of the preceding claims, wherein the spine is carbon fibre or magnesium alloy.