NL2029222B1

NL2029222B1 - Folding stroller

Info

Publication number: NL2029222B1
Application number: NL2029222A
Authority: NL
Inventors: Geert Arie Den Boer Jacob; Jacob Paul De Vries Frank; Cornelis Simon Koopman Rutger
Original assignee: Royalty Bugaboo Gmbh
Priority date: 2021-09-22
Filing date: 2021-09-22
Publication date: 2023-03-29

Abstract

A foldable stroller is provided, which is movable between an unfolded condition and a folded condition. The foldable stroller comprises a front leg to which a front wheel is mounted, a rear leg to which a rear wheel is mounted, a telescopic handlebar comprising a push bar for a user to push the stroller and which is configured so as to be horizontal when the front and rear wheels contact the ground with the stroller unfolded, an inner tube and an outer tube, wherein the push bar is connected to one of the inner tube and the outer tube, and wherein the inner tube has a releasable engagement with the outer tube which, when released, enables the inner tube to slide within the outer tube to adjust the height of the push bar between predetermined minimum and maximum handlebar heights for pushing the stroller, a jointjoining the front leg, rear leg and the telescopic handlebar, first and second controls provided on the push bar for selective operation by a user; and a releasable locking mechanism which when engaged holds the front leg, rear leg and telescopic handlebar in fixed position relative to each other so as to hold the stroller in its unfolded condition and which when released permits relative rotational movement, around a rotational axis of the joint, between the handlebar and the front and rear legs so as to permit the stroller to be moved to its folded condition. User operation ofthe first control releases the engagement between the inner tube and the outer tube to adjust the height of the push bar, and user operation of the second control enables the inner tube to be slid further into the outer tube, beyond the predetermined minimum handlebar height position for pushing the stroller, to a position at which a leading edge of the inner tube releases the releasable locking mechanism to enable the stroller to be moved to its folded condition.

Description

Folding stroller

Field of the invention

The present invention relates to a folding stroller.

Background

Strollers provide a convenient means for a parent or other carer to transport a child (whether a newborn, toddler or small child). Strollers are however typically relatively large and bulky.

Foldable stroller designs have been proposed, to permit the stroller to be folded and therefore occupy less space and generally be more manageable by a user e.g. for storage or transport of the folded stroller.

For example, foldable strollers are known in which a foldable bassinet or seat is mounted on a foldable wheeled chassis frame. When both bassinet/seat and wheeled chassis frame are unfolded, a user may safely transport an infant using the stroller. After use the stroller may be folded e.g. for storage or transport.

Folding strollers are typically provided with a locking mechanism which must be actively released to move the stroller from its unfolded condition to its folded condition and thus to prevent inadvertent folding of the stroller whilst carrying an occupant. Existing designs however typically require two separate locking mechanisms to be released e.g. one on each side of the handle of the stroller, requiring a two-handed (and therefore inconvenient) process for a user.

Additionally, existing folding stroller designs are typically subject to “play” or excess movement in the frame when in its unfolded condition, which may detrimentally effect steering of the stroller and may increase wear in parts subject to play.

Embodiments of the present invention seek to address these drawbacks of the prior art.

Statements of invention

According to a first aspect of the present invention, there is provided a foldable stroller movable between an unfolded condition and a folded condition and comprising: a front leg to which a front wheel is mounted;

a rear leg to which a rear wheel is mounted; a telescopic handlebar comprising a push bar for a user to push the stroller and which is configured so as to be horizontal when the front and rear wheels contact the ground with the stroller unfolded, an inner tube and an outer tube, wherein the push bar is connected to one ofthe inner tube and the outer tube, and wherein the inner tube has a releasable engagement with the outer tube which, when released, enables the inner tube to slide within the outer tube to adjust the height of the push bar between predetermined minimum and maximum handlebar heights for pushing the stroller; a joint joining the front leg, rear leg and the telescopic handlebar; first and second controls provided on the push bar for selective operation by a user; and a releasable locking mechanism which when engaged holds the front leg, rear leg and telescopic handlebar in fixed position relative to each other so as to hold the stroller in its unfolded condition and which when released permits relative rotational movement, around a rotational axis of the joint, between the handlebar and the front and rear legs so as to permit the stroller to be moved to its folded condition; wherein user operation of the first control releases the engagement between the inner tube and the outer tube to adjust the height of the push bar; and wherein user operation of the second control enables the inner tube to be slid further into the outer tube, beyond the predetermined minimum handlebar height position for pushing the stroller, to a position at which a leading edge of the inner tube releases the releasable locking mechanism to enable the stroller to be moved to its folded condition.

Preferably, the releasable locking mechanism comprises a contact portion which is pressed by the leading edge of the inner tube to release the releasable locking mechanism.

Preferably, the releasable locking mechanism comprises a locking portion movable between a first position at which the locking portion engages with both the telescopic handlebar and at least one of the front and rear legs, and a second position at which the locking portion is disengaged from the telescopic handlebar or disengaged from said at least one of the front and rear legs.

Preferably, the releasable locking mechanism further comprises a locking release portion which is configured to be rotated around the rotational axis of the joint when the leading edge of the inner tube releases the releasable locking mechanism, and wherein the locking portion and the locking release portion are each provided with cam surfaces which contact each other and co-operate so that said rotation of the locking release portion around the rotational axis moves the locking portion from its first position to its second position.

Preferably, the first and second controls are located adjacent each other on the push bar to enable their simultaneous operation by a user using one hand.

Preferably, the inner tube and outer tube are provided on a first lateral side of the stroller, wherein the handlebar further comprises a second inner tube and a second outer tube on a second lateral side of the stroller, with the push bar being connected also to one of the second inner tube and second outer tube, and wherein user operation of the first control also releases an engagement between the second inner tube and the second outer tube, simultaneously with the release of the engagement between the inner tube and the outer tube on the first lateral side of the stroller, to enable the height of the push bar to be adjusted.

Preferably, the front leg, rear leg and joint are also provided on the first lateral side of the stroller, wherein the stroller further comprises a second front leg, rear leg and joint provided on the second lateral side of the stroller with an associated second releasable locking mechanism, and wherein user operation of the second control also enables the second inner tube to be slid further into the second outer tube, beyond the predetermined minimum handlebar height position for pushing the stroller, to a position at which a leading edge of the second inner tube releases the second releasable locking mechanism to enable the stroller to be moved to its folded condition.

Preferably, the foldable stroller further comprises a cavity provided in a first of {i} the handlebar and (ii) the front or rear leg of the stroller and in which an engagement element and a biasing element are provided, the biasing element biasing the engagement element to protrude from the cavity, and a receiving portion provided in a second of (i) the handlebar and (ii) the front or rear leg of the stroller, the receiving portion configured to receive the engagement element when the stroller is in its unfolded condition, so that a first part of the engagement element is located within the cavity and a second part of the engagement element is located within the receiving portion.

Preferably, the engagement element has a convex rounded surface and the receiving portion has a corresponding concave rounded surface so that the engagement element may roll out of the receiving portion, to retract into the cavity against the bias of the biasing element, when the handlebar and front and rear legs rotate relative to each other around the rotational axis of the joint.

Preferably, the engagement element comprises a spherical element and the receiving portion comprises a semi-circular recess.

According to a second aspect of the present invention, there is provided a foldable stroller movable between an unfolded condition and a folded condition and comprising: a leg to which a wheel is mounted; a handlebar; a joint joining the leg and the handlebar and around a rotational axis of which the handlebar and the leg are rotatable relative to each other to fold the stroller; wherein a cavity is provided in a first of (i} the handlebar and (ii) the leg of the stroller and in which an engagement element and a biasing element are provided, the biasing element biasing the engagement element to protrude from the cavity, and a receiving portion provided in a second of (i) the handlebar and (ii) the leg of the stroller, the receiving portion configured to receive the engagement element when the stroller is in its unfolded condition, so that a first part of the engagement element is located within the cavity and a second part of the engagement element is located within the receiving portion.

Preferably, the engagement element has a convex rounded surface and the receiving portion has a corresponding concave rounded surface so that the engagement element may roll out of the receiving portion, to retract into the cavity against the bias of the biasing element, when the handlebar and leg rotate relative to each other around the rotational axis of the joint.

List of figures

In order that the present invention may be more readily understood, embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which: 5

FIGURES 1A and 18 show front and rear perspective views of a stroller according to an embodiment of the present invention in an unfolded condition;

FIGURE 2 shows the stroller of Fig. 1 in a folded condition;

FIGURES 3A to 3D schematically show handlebar height adjustment and the folding process ofthe stroller of Fig. 1, and FIGURES 3E to 3G are cross-sectional views of an internal portion of the handlebar during these procedures;

FIGURE 4 shows a central joint of the stroller of Fig. 1 in greater detail;

FIGURE 5 is a partial cutaway view of the central joint of Fig. 4;

FIGURES 6A to 6C are exploded perspective views of selected components of the central joint of Fig. 4;

FIGURES 7A to 7C are schematic cross-sectional views of the central joint of Fig. 4;

FIGURES 8A to 8C are partial cutaway views of a play-reduction mechanism of the central joint of Fig. 4; and

FIGURE 9 is a schematic cross-sectional view of the play-reduction mechanism of the central joint of Fig. 4.

Description of exemplary embodiments

A foldable stroller 1 according to an embodiment of the present invention is shown in its unfolded condition in Figs. 1A and 1B and in its folded condition in Fig. 2, with the folding process shown schematically in the sequence of Figs. 3A to 3D.

The stroller 1 broadly consists of a pair of rear wheels 3 attached to a pair of rear legs 5 (i.e. legs closest to a user when pushing the stroller 1 by its handle) which legs 5 are joined by a first lateral cross bar 6, a pair of front wheels 7 swivel-mounted to a pair of front legs 9 (i.e. legs 9 distal from a user when pushing the stroller 1 by its handle} which legs 9 are joined by a second lateral cross bar 10, and a telescopic handlebar 11 for pushing the stroller 1, with the telescopic handlebar 11 comprising a pair of outer tubes 13, one on each lateral side of the stroller 1, within which inner tubes 15 may slide upon proper actuation of primary 16a and secondary 16b actuator buttons of a control panel 17 mounted centrally on a horizontal push bar or cross bar 19 linking the two inner tubes 15, to adjust the height of the push bar 19.

There are a number of different predetermined height positions where the inner tubes 15 are fixed relative to the outer tubes 13. In order to adjust the height of the push bar 19, the primary actuator button 16a is pressed by a user, resulting in cables (not shown} within the handlebar 11 being pulled to retract a movable protruding element 15a provided on the inner tube 15 from engagement with one of a plurality of recesses 13a provided on the outer tube 13 (see figs. 3E and 3F — Fig. 3E shows the engaged position prior to a user pressing button 16a, and Fig. 3F shows the retracted/disengaged position when that button 16a is pressed), thus to release the fixation of the inner tubes 15 relative to the outer tubes 13 (see Fig. 3B).

Each recess 13a corresponds to a different handle height. A minimum predetermined handle height is determined and enforced by the presence of an end stop protrusion 20 on the outer tube 13, which blocks the retracted protruding element 15a, and hence the inner tube 15 overall, from moving further into the outer tube 13.

When a desired lower or higher handle bar position is reached, the primary actuator button 16a can be released, causing the movable protruding element 15a provided on the inner tube 15 to engage with a further one of the corresponding recesses 13a, such that the push bar 19 is fixed at a new height.

The secondary actuator button 16b of the control panel 17 is used when releasing the stroller 1 for folding and is described further below.

On each lateral side of the stroller 1, a central joint 21 connects the rear legs 5, front legs 9 and outer tubes 13 of the handlebar 11. A seatlug 23 is also provided on each central joint 21, on which a seat, carrycot/bassinet or car seat can be removably mounted to complete the stroller 1 for use (seat 25 is shown connected to the seatlugs 23 in Fig. 1, by way of example).

The central joints 21 on either side of the stroller 1 are joined by a central joint crossbar 27, to provide further rigidity to the stroller 1 and also to provide each central joint 21 with a central axis around which the handlebar outer tube 13, rear leg 5 and front leg 9 (and seat lug 23) can rotate to allow the stroller 1 to be placed into its folded condition.

A first of the two central joints 21 will now be described with reference to Fig. 4 onwards; the second of the two central joints 21 takes the same configuration and hence is not described separately. As shown in Figs. 4 and 5, the ends of the handlebar 11, front 9 and rear legs 5 and seatlug 23 which abut at the central joint 21 are hollow to define a housing of the central joint 21, into which one end of the crossbar 27 protrudes to provide a rotational center for the handlebar 11 and front 9 and rear 5 legs during the folding process. Also located within the joint housing is a releasable locking mechanism comprising first 29a and second 29b locking rings, a lever 30 and a cylindrical disk or collar 31 (see Figs. 6A and 6B) having externally protruding cam portions 33. Here, Figs. 6A and 6B show the relation between the first locking ring 29a, the collar 31, the handlebar outer tube 13 and the rear leg 5. A corresponding relation is provided between the second locking ring 29b, the collar 31, the front leg 9 and the seat lug 23.

The cylindrical collar 31 is slid onto a tube 34 which extends from the seat lug 23 (see Fig. 6C), and which connects the seat lug 23 and the handlebar outer tube 13 by bosses 34a on an end face of the tube 34 mating with corresponding recesses 34b in the handlebar outer tube 13, to prevent relative rotation between the seat lug 23 and the handlebar outer tube 13. Hence, when the handlebar 11 rotates around the central joint 21, the seat lug 23 also rotates, together with the handlebar 11.

The central joint crossbar 27 protrudes into the interior 34c of the tube 34 to connect the central joint crossbar 27 to the central joint 21. The locking rings 29a, 29b are slid onto the cylindrical collar 31 so that female cam surfaces 35 provided on the inner surface of each locking ring 29a, 29b contact co-operating male cam surfaces 37 of the protruding cam portions 33.

The shape of each locking ring 29a, 29b is such that it cannot rotate around the central axis relative to either the handlebar 11 or the seatlug 23. In particular, each locking ring 29a, 29b has external protrusions or teeth 39 so as to generally resemble a cog. The protrusions 39 of the first locking ring 29a locate within corresponding recesses 41 within the hollow end portion of the handle outer tube 13, thus preventing relative rotational movement between those parts. Similarly (and hence not illustrated) the protrusions 39 of the second locking ring 29b locate within corresponding recesses within the hollow end portion of the seatlug 23.

Both locking rings 29a, 29b are however able to translate laterally along the rotational axis of the central joint 21 defined by the crossbar 27, by sliding laterally over the external surface of the cylindrical collar 31. This enables the first and second locking rings 29a, 29b to be selectively engaged and disengaged with the rear leg 5 and front leg 9 of the central joint 21, in turn either locking the stroller 1 in its unfolded condition, or permitting folding.

In the unfolded condition of the stroller 1, the protrusions 39 of the first locking ring 29a engage with corresponding recesses 43 in the hollow end of the rear leg 5, in addition to engaging with the recesses 41 of the outer tube 13 of the handlebar 11 (see Fig. 7A). Hence, inthe unfolded state, the first locking ring 29a acts to bridge or connect the outer tube 13 of the handlebar 11 and the rear leg 5, preventing relative movement between those components. Similarly, the protrusions 39 of the second locking ring 29b engage with corresponding recesses in both the front leg 9 and the seatlug 23, with the consequence that the front-leg 9 and seatlug 23 cannot rotate around the central axis relative to each other. In addition to these connections, the seat lug 23 is non-rotatably connected to the handlebar outer tube 13 by the tube 34 within the central joint. As a result, the rear and front legs 5, 9 and handlebar outer tube 13 (and seat lug 23) are fixed relative to each other to prevent inadvertent folding of the stroller 1.

In contrast, and as further described below, when adopting the folded condition, the first and second locking rings 29a, 29b are moved out of engagement with the rear and front legs 5, 9 (see Figs. 7B and 7C), enabling the rear and front legs 5, 9 and handlebar outer tubes 13 to rotate freely and independently towards each other around the central axis for reaching a folded more compact stroller condition.

In order to fold the stroller 1, the handlebar 11 firstly has to be adjusted to its lowest height usage position, by a user pressing the primary actuator button 16a and depressing the handle 11 to adjust handle height to the lowest setting, in the manner described above (see Fig. 3B).

From there, folding is initiated by sliding the inner tubes 15 of the handlebar 11 even further into the outer tubes 13. In order to do this, the user actuates the secondary actuator button 16b of the control panel 17 on the handlebar 11; with this second button 16b pushed in, the primary actuator button 16a is permitted to be pushed an additional distance into the control panel 17, pulling still further on the cables (not shown) located with the handlebar 11 and thus further retracting the movable protrusion 15a of the inner tube 15 so that it can clear the end stop protrusion 20 (see fig. 3G), thus enabling the handlebar inner tube 15 to slide lower in the handlebar outer tube 13, beyond its normal usage positions.

This further handlebar movement results in the leading edge of each inner tube 15 pressing the lever 30 located within its respective central joint 21. The lever 30 in turn presses against a projection 44 formed on the cylindrical collar 31, causing the cylindrical collar 31 to rotate around the rotational axis of the central joint 21. This rotation of the cylindrical collar 31 moves the male angular cam-surfaces 37 of the cylindrical collar 31 relative to the corresponding female angular cam-surface 35 on the first and second locking rings 29a, 29b, forcing the first and second locking rings 29a, 29b to translate laterally along the central axis (see arrows in Fig. 7B), by sliding over the outer surface of the cylindrical collar 31to a position where the protrusions 39 of the locking rings 29a, 29b are only engaged with the corresponding recesses 41 of the handlebar outer tube 13 and seatlug 23, and disengaged from the corresponding recesses 43 of the rear- and front-legs 5, 9 (see Fig. 7C). This means that now the front- and rear leg 5, 9 can rotate freely relative to each other and to the handlebar outer tube 13. That is, contact by the leading edge of the inner tube 15 with a contact portion (the lever 30) of the releasable locking mechanism results in the releasable locking mechanism being released so that the handlebar 11 and front and rear legs 9, 5 of the stroller 1 are freed to rotate independently around the central joint 21 (see Fig. 3C) until the stroller 1 adopts its folded condition {see Fig. 3D).

So when folding the stroller 1 by pushing in the handlebar leg completely, the cylindrical collar 31 rotates, the locking rings 29a, 29b move laterally and the handlebar 11, rear- and front leg 5, 9 get disconnected and can rotate freely to a folded more compact position.

When unfolding, when reaching the unfolded position, two springs (not shown) push the locking rings 29a, 29b back into the locked position of Fig. 7A, locking the handlebar outer tube 13, front- and rear leg 9, 5 relative to each other.

As will be appreciated, a user may operate both the primary and secondary actuator buttons 16a, 16b, and depress the handle 11 of the stroller 1, using one hand. Hence, a user may conveniently unlock the stroller 1 for folding by a one-handed operation, leaving the other hand of the user free for another operation e.g. to hold the hand of a child previously the occupant of the stroller 1.

The present embodiment is additionally provided with an anti-play mechanism.

Here, due to the construction of the whole strollers, which contains of several mass-produced parts with certain defined production tolerances, the handlebar when fixated to the handlebar legs, may have a little free angular movement relative to the front and rear legs, called ‘play’. This is undesirable, as the play results in a less rigid stroller structure which may be harder and/or less direct for a user to steer, and/or may cause undue wear on parts moving relative to each other as a result of this play (e.g. when the stroller is pushed over uneven ground).

To reduce or avoid this play altogether, the present embodiment is provided with the anti- play mechanism shown in Figs. 8A to 8C and 9. Here, each outer tube 13 of the handlebar 11 has in the central joint area two slots or recesses 45 in which two round balls 47 of hard material {e.g. stainless steel ball bearings) are respectively located to translate parallel to the rotational axis of the central joint 21 (i.e. towards and away from the rear leg 9 of the central joint 21). In the unfolded position, these balls 47 are biased by a respective spring 49 into engagement with a corresponding semi-circular receiving portion 51 on the rear leg 5 (see fig. 8C}, so as to be located with part of the ball 47 in the receiving portion of the rear leg 5 and part of the ball 47 in the slot 45 of the outer tube 13 of the handle 11. Hence, in the unfolded condition, these balls 47 provide a bridging physical connection between the outer tube 13 of the handlebar 11 and the rear leg 5, thus to diminish or avoid altogether the play between them.

When the stroller folds, and the outer tube 13 of the handlebar 11 rotates around the central axis independently of the rear leg 5, the round shape of the balls 47 enables them to roll out of the receiving portion 51 in the rear leg 5, and to retract into the slots 45 in the handlebar outer tube 13 (against the bias of the spring 49}, removing the connection between the outer tube 13 of the handle bar 11 and the rear leg 5 and thus permitting the stroller 1 to fold without “jamming” — see Fig. 8B. Hence, the anti-play mechanism acts to reduce relative movement between the handlebar 11 and the rear leg 5 so as to reduce/avoid “play”, but not to the extent of interfering with the proper folding of the stroller 1. When the stroller 1 is unfolded once more, the balls 47 are biased by the springs 49 back into the semi-circular receiving portions 51 within the rear leg 5, to reduce/avoid play once more.

The same construction is also applied between the seatlug 23 and the front leg 9 (as shown schematically in Fig. 9), to diminish or avoid altogether the play between those elements also when the stroller 1 is in the unfolded condition, but without interfering with the proper folding of the stroller 1.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Thus, the foregoing embodiments of the invention have been described by way of example only. lt will be appreciated by a person skilled in the art that various modifications can be made without departing from the scope of the invention as defined by the claims. The following sets out a non-exhaustive selection of modifications, being also embodiments of the present invention.

Exemplary modifications

In the above-described stroller embodiment, the first and second locking rings 29a, 29b are caused to disengage with the rear and front legs 5, 9 while remaining engaged with the handlebar outer tube 13 and seat lug 23, respectively, to enable the stroller 1 to fold.

However, this may be reversed i.e. the first locking ring 29a may instead be disengaged from the handle outer tube 13 while remaining engaged with the rear leg 5 and/or the second locking ring 29b may instead be disengaged from the seat lug 23 while remaining engaged with the front leg 9.

Furthermore, in the above-described embodiment, the first locking ring 29a provides a releasable connection between the handlebar 11 and the rear leg 5 and the second locking ring 29b provides a releasable connection between the seat lug 23 and the front leg 9. This is primarily determined by the fact that the handlebar outer tube 13 and rear leg 5 are adjacent at the joint 21 and the front leg 9 and seat lug 23 are adjacent at the joint 21. However, different arrangements may be provided e.g. the handlebar 11 and front leg 9 may be adjacent at the joint 21, with the first locking ring 29a providing a releasable engagement between them, etc.

In the anti-play mechanism of the above embodiment, the slot 45, ball 47 and biasing element 49 are provided in the handlebar 11, whereas the receiving portion 51 is provided in the rear leg 5. However, this may be reversed. Also, although a spherical element (ball 47} is used in the foregoing embodiment, other rounded elements may be used instead e.g. cylindrical or ovoid elements, with the concave receiving portion 51 altered to correspond accordingly. Furthermore, although the above described embodiment utilises two balls, slots and receiving portions to reduce play between adjacent elements, a lesser or greater number may be used e.g. a single ball, slot and receiving element.

References to a “stroller” are to be interpreted as including prams, buggies and pushchairs.

Also, although a stroller embodiment intended for a child or infant is described above, it will be appreciated that aspects of the present invention may be applied to a wheelchair for a child or adult. References to a “stroller” are therefore also to be interpreted as including wheelchairs for children or adults.

Claims

Claims L Foldable stroller movable between an unfolded state and a folded state, and comprising: a front leg to which a front wheel is mounted; a hind leg to which a rear wheel is mounted; a telescoping handlebar that includes a push bar for a user to push the stroller and is configured so as to be horizontal when the front and rear wheels are in contact with the ground and the stroller is unfolded, an inner tube and an outer tube, the push rod is connected to one of the inner tube and the outer tube, and the inner tube has a releasable engagement with the outer tube which, when disengaged, allows the inner tube to slide within the outer tube to adjust the height of the push bar between predetermined minimum and maximum handlebar heights for pushing the stroller; a connecting piece that connects the front leg, rear leg and the telescopic handlebars; first and second controls provided on the push rod for selective operation by a user; and a releasable locking mechanism which, when engaged, maintains the front leg, rear leg and telescopic handlebars in a fixed position relative to each other so as to maintain the stroller in its unfolded condition and, when disengaged, allows relative rotational movement between the handlebars and permitting the front and rear legs about an axis of rotation of the connector so as to permit the stroller to be moved to its folded condition, wherein operation by a user of the first controller releases the engagement between the inner tube and the outer tube to adjust the height of the push bar; and wherein operation by a user of the second adjuster allows the inner tube to be advanced further into the outer tube, beyond the predetermined minimum push bar height position for pushing the stroller, to a position where a leading edge of the inner tube detaches from the releasable locking mechanism to allow the stroller to be moved to its folded position.

The foldable stroller of claim 1, wherein the releasable locking mechanism includes a contact portion pressed against by the front edge of the inner tube to release the releasable locking mechanism.

A foldable stroller according to claim 1 or 2, wherein the detachable locking mechanism comprises a locking portion movable between a first position where the locking portion engages both the telescopic handlebar and at least one of the front and rear legs, and a second position where the locking portion is disconnected from the telescopic handlebars or disconnected from at least one of the front and rear legs.

The foldable stroller of claim 3, wherein the releasable locking mechanism further comprises a lock release portion configured to be rotated about the axis of rotation of the link when the front edge of the inner tube releases the releasable locking mechanism, and wherein the lock portion and the lock release portion each provided with cam surfaces that contact each other and cooperate so that rotation of the latch release portion about the pivot axis moves the latch portion from its first position to its second position.

A foldable stroller according to any preceding claim, wherein the first and second controls are adjacent to each other on the push bar to allow simultaneous operation thereof by a user using one hand.

A foldable stroller according to any preceding claim, wherein the inner tube and outer tube are provided on a lateral side of the stroller, the handlebars further comprising a second inner tube and a second outer tube on a second lateral side of the stroller, the push bar also being connected is with one of the second inner tube and second outer tube, and wherein operation by a user of the first regulator also releases engagement between the second inner tube and the second outer tube, simultaneously with the release of engagement between the inner tube and the outer tube on the first side of the stroller, to allow the height of the push bar to be adjusted.

A foldable stroller according to claim 6, wherein the front leg, rear leg and connector are also provided on the first lateral side of the stroller, the stroller further comprising a second front wheel, rear wheel and connector provided on the second lateral side of the stroller having an associated second releasable locking mechanism, and wherein operation by a user of the second controller also allows the second inner tube to be further advanced into the second outer tube, beyond the predetermined minimum handlebar height position for pushing the stroller, to a position where a front edge of the second inner tube releases the second releasable locking mechanism to allow the stroller to be moved to its folded position.

A foldable baby stroller according to any one of the preceding claims, further comprising a cavity provided on a first of (i) the handlebars and (ii) the front or rear leg of the baby stroller and wherein a gripping member and a biasing member are provided, wherein the biasing member biases the gripping member to protrude from the cavity, a receiving portion provided in a second of (1) the handlebar and (11) the front or rear leg of the pushchair, the receiving portion being configured to hold the gripping member received when the stroller is in its unfolded condition, so that a first part of the gripping member is located within the cavity and a second part of the gripping member is located within the receiving portion.

A foldable stroller according to claim 8, wherein the gripping member has a convex rounded surface and the receiving portion has a corresponding concave rounded surface to allow the gripping member to roll out of the receiving portion to retract into the cavity against the bias of the biasing member, when the handlebars and the front and rear legs rotate relative to each other about the axis of rotation of the joint.

A foldable stroller according to claim 9, wherein the gripping element comprises a spherical element and the receiving portion comprises a semi-circular recess.

A foldable baby stroller movable between an unfolded state and a folded state, and comprising: a leg having a wheel mounted on it; a steering wheel; a connector connecting the leg and the handlebars and about a pivot axis about which the handlebars and the leg can be rotated relative to each other to fold the pushchair; wherein a recess is provided in a first of (1) the handlebar and (ii) the leg of the stroller and wherein a gripping member and biasing member are provided, the biasing member biasing the gripping member to protrude from the recess, and a receiving portion which provided in a second of (1) the handlebar and (ii) the leg of the pushchair, the receiving portion being configured to receive the gripping member when the pushchair is in its unfolded condition, so that a first portion of the gripping member is within the cavity and a second part of the gripping element is located within the receiving portion.

A foldable baby stroller according to claim 11, wherein the gripping member has a convex rounded surface and the receiving portion has a corresponding concave rounded surface to allow the gripping member to roll out of the receiving portion to retract into the cavity against the bias of the biasing member when the handlebar and leg rotate relative to each other about the axis of rotation of the joint.

A foldable stroller according to claim 12, wherein the gripping element comprises a spherical element and the receiving portion comprises a semi-circular recess.