NL2020064B1

NL2020064B1 - Compact foldable stroller

Info

Publication number: NL2020064B1
Application number: NL2020064A
Authority: NL
Inventors: Mattijs Dijkstra Aernout; Anton Magerl Christoph; Stefan Munster Jaco
Original assignee: Royalty Bugaboo Gmbh
Priority date: 2017-12-12
Filing date: 2017-12-12
Publication date: 2019-06-21
Also published as: CN109910979A

Abstract

A foldable chair (2) for a stroller is described comprising a backrest frame (21), a seat frame (22), two coupling elements (23) for removably coupling the chair to the stroller and two frame joints (24) for rotatably connecting the coupling elements to the backrest frame and the seat frame. Each frame joints comprises a first ring (74) fixed to one of the coupling elements and comprising two limiters (125,129), a second ring (71) fixed to the one of the coupling elements and comprising two limiters (134,135) and at least one notch (109) at a circumference, a seat ring (96) fixed to the seat frame (21) and being arranged between the first and second ring, the seat ring comprising at least one notch (102) at a circumference, a backrest ring (92) fixed to the backrest frame and being arranged between the seat ring and the second ring (71), the backrest ring comprising a corridor (94) extending in a radial direction, and a backrest locker (93) movably arranged in the corridor (94) of the backrest ring (92), wherein the foldable chair (2) can be manually changed from a folded state to an unfolded state, by rotating the back rest frame and the seat frame.

Description

COMPACT FOLDABLE STROLLER

FIELD OF THE INVENTION

The invention relates to a compact foldable stroller, and more specifically to a foldable chair for such a stroller. A stroller is also referred to as a buggy.

BACKGROUND ART

Patent application WO2010/050804 describes a chair at the front of a child buggy. The chair comprises a seat and a backrest, the backrest being displaceable in its position with respect to the seat between at least one use position in which an infant can be placed in the chair and at least one folded position in which no infant can be placed in the seat. The chair comprises two coupling elements to be used for detachably coupling the chair to a coupling member of the child buggy. A locking element is arranged to lock the coupling between the child's chair and the child buggy when the backrest is in a use position and to allow the chair to be detachable from the child buggy when the backrest is in a folded position.

Although both the buggy and the chair can be folded to make them more compact for storage, they will still be too large for an overhead compartment in an airplane. So the folded stroller will not have a size in line with the requirements for carry-on airline hand luggage.

SUMMARY OF THE INVENTION

One of the objects of the invention is provide a foldable seat for a stroller which is more compact as compared to known seats.

The invention provides a foldable chair for a stroller, the foldable chair comprising: - a backrest frame; - a seat frame; - two coupling elements for removably coupling the chair to the stroller; - two frame joints for rotatably connecting the coupling elements to the backrest frame and the seat frame, wherein the backrest frame and the seat frame can rotate around an axis of rotation and wherein each of the frame joints comprises: - a first ring fixed to one of the coupling elements and comprising two limiters; - a second ring fixed to the one of the coupling elements and comprising two limiters and at least one notch at a circumference.

The foldable chairs is characterized in that it also comprises: - a seat ring fixed to the seat frame and being arranged between the first and second ring, the seat ring comprising at least one notch at a circumference; - a backrest ring fixed to the backrest frame and being arranged between the seat ring and the second ring, the backrest ring comprising a corridor extending in a radial direction, and - a backrest locker movably arranged in the corridor of the backrest ring, wherein the foldable chair can be manually changed from a folded state to an unfolded state, by rotating the back rest frame and the seat frame.

Using a locker that can radially move into a notch of the second ring or into a notch of the seat ring enables a relative locking of the backrest frame and seat frame that can be achieved using a single manual rotation of one of the frames. There is no need for activating or releasing a locker. The locking can be automatically executed by simply rotating the seat frame or the backrest frame relative to one another.

Because the four rings and the end stops positions are concentric to each other around axis of rotation, the frame joint can be made very thin. This will enable a very thin design of the foldable chair.

Optionally, wherein the first ring is an inner ring coaxially arranged within the second ring, referred to as the outer ring, wherein, the outer ring comprising the at least one notch at an inner circumference, wherein the at least one notch in the seat ring is arranged at an outer circumference of the seat ring.

Optionally, in the folded state the backrest frame and the seat frame can freely rotate around the axis, until the backrest ring is blocked by one of the limiters while the seat rest ring can rotate further, wherein, due to this further rotation of the seat ring, the backrest locker is urged out of the notch of the seat ring and into the notch of the second ring, and wherein the backrest locker is secured into the notch of the second ring by a circumference of the seat ring.

Optionally, the seat ring comprises a corridor, and wherein the backrest ring comprises at least one notch at a circumference, wherein each of the frame joints comprises a seat locker movably arranged in the corridor of the seat ring.

Optionally, the backrest locker comprises a body having a body part, at least in use, extending in the radial direction and having a cross section in a plane perpendicular to the axis of rotation which cross section shows a rectangular middle section and two tapered or wedge-shaped outer sections.

The presence of a middle section is advantageous when moving the locker through a straight corridor. A tapered/wedge-shaped sections are advantageous because then the lockers can easily be urged out of the notches.

Optionally, the second ring comprises at least one further notch arranged next to the notch, wherein the backrest locker can be moved in a direction parallel to the axis of rotation and out of the notch, wherein due to a further rotation of the backrest frame, the backrest locker falls into one of the at least one further notches.

Optionally, the backrest frame comprises a reclining mechanism for reclining the backrest from a first backrest orientation into a second backrest orientation, wherein the reclining mechanism comprises a recline button arranged in the backrest frame and the backrest locker, and wherein the activate the recline button will displace the backrest locker.

Optionally, the frame joints are disc shaped, having a width w, having a value preferably less than 20 mm.

According to a further aspect, there is provided a foldable stroller, the foldable stroller comprising: - a foldable chair according to any of the preceding claims; - a foldable stroller frame comprising two dockings, each of the docking being arranged to receive one of the coupling elements, so as to docket the foldable chair into the stroller frame.

Optionally, the stroller frame comprises two telescopic bars and two handles, each of the handles being arranged on one of the telescopic bars and arranged to activate an unlocking mechanism for enabling the folding of the stroller frame, wherein activation of the handles can blocked by a blocking mechanism arranged in the coupling element when the chair is folded.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the invention are apparent from and will be elucidated with reference to the embodiments described hereinafter. In the drawings,

Figure 1 schematically shows a side view of an embodiment of the foldable stroller;

Figure 2 schematically shows a perspective view of the foldable stroller of Figure 1 in a completely folded state;

Figure 3 schematically shows a side view of the foldable stroller of Figure 1 but in a simplified way;

Figure 4 schematically shows a side view of the foldable stroller with the chair in a nearly folded state;

Figure 5 schematically shows a perspective view of part of the stroller frame according to an embodiment;

Figure 6 shows a coupling member in more detail;

Figure 7A schematically shows a detailed view of the coupling member with the frame joint docketed;

Figure 7B schematically shows a front view of an example of the inner ring;

Figure 8 shows a perspective view of the other side of the frame joint together with the coupling element;

Figure 9A shows a perspective view of a part of the backrest frame;

Figure 9B shows a perspective view with cutout of a part of the frame joint and the coupling element;

Figure 9C shows a perspective view of the seat ring with seat which comprises a corridor in which a seat locker is movably arranged;

Figure 9D shows a side view of the backrest ring according to an embodiment;

Figure 10 shows a cut out view of the frame joint with the four rings being assembled together;

Figures 11-27 are built up with an A, B and C section, wherein section A shows a side view of the stroller in a simplified way to show the orientation of the backrest frame and the seat frame, section B of the drawings shows an open side view of the frame joint, and section C shows a schematic cross section of the frame joint, presented in a way wherein the X-direction of the C section represents the tangential direction of the physical structure shown in the corresponding section B;

Figure 28 schematically shows parts of the backrest frame and a cable which at a first outer end is coupled to the recline button;

Figure 29 schematically shows a cut perspective view of a frame joint and some parts of the chair;

Figure 30 shows a detailed side view of the joint in a fully folded state of the chair;

Figure 31 shows a detailed side view of the joint in a nearly folded state of the chair;

Figures 32A, 32B, 33A and 33B show a further embodiment of the frame joint;

Figure 34 shows some further possible examples of the cross section of the locker in a plane rectangular to the axis of rotation, and

Figure 35 shows a possible 3D configuration of the locker.

It should be noted that items which have the same reference numbers in different Figures, have the same structural features and the same functions. Where the function and/or structure of such an item has been explained, there is no necessity for repeated explanation thereof in the detailed description.

DETAILED DESCRIPTION OF EMBODIMENTS

Figure 1 schematically shows a side view of an embodiment of the foldable stroller. The stroller comprises a frame 1 with two telescopic bars 10 connected at the top by a handle bar 15. In an embodiment, the handle bar 15 is pivotably connected to the telescopic bars 10. Furthermore, the stroller frame 1 comprises two support structures 11 rotatably coupled to the telescopic bars 10. Two rear wheels 12 are coupled to a lower outer end of the support structures 11 and two front wheels 13 are coupled to a lower outer end of the telescopic bars 10. In Figure 1, a foldable chair 2 is coupled to the stroller frame 1. The foldable chair 2 comprises a backrest frame 21, a seat frame 22 and two coupling elements 23 (see also Figure 3) for removably coupling the chair 2 to the stroller frame 1. The chair 2 also comprises two frame joints 24 for rotatably connecting the coupling elements 23 to the backrest frame 21 and the seat frame 22, wherein the backrest frame 21 and the seat frame 22 can rotate around a rotational axis 90 (see also Figure 3). In the example of Figure 1 a canopy 25 is coupled to the chair 2. The canopy provides for comfort for the child in the sense that it protects the child against rain, wind, sunshine or noise. The canopy 25 may be foldable. In an embodiment, the canopy 25 is removable from the backrest frame 21.

Figure 2 schematically shows a perspective view of the foldable stroller of Figure 1 in a completely folded state. The telescopic bars 10 are in their shortened configuration, and the handle bar 15 is rotated relative to the telescopic bars 10 to make an angle of about 90 degrees, so that the folded stroller is made as compact as possible. Figure 2 shows a recline button 26 arranged in the backrest frame 21. This recline button 26 can be manually activated to recline the backrest frame 21 when the chair is in the unfolded state, as will be explained in more detail below. In a preferred embodiment, the folded stroller has height x depth x width dimensions equal or less than 55cm x 40cm x 20cm.

Figure 3 schematically shows a side view of the foldable stroller of Figure 1 but in a simplified way. Figure 3 schematically shows one of the frame joints 24 which is arranged to join the backrest frame 21, the seat frame 22 and the coupling element 23 in a rotatable manner. Figure 3 shows the stroller in a use-position, meaning that the seat is mounted onto the stroller frame and in an unfolded state.

Figure 4 schematically shows a side view of the foldable stroller in a nearly folded state. Arrows in Figure 4 show the direction of rotation of the different elements. Starting from Figure 3, the user (i.e. the caretaker) has activated the recline button and pulled the backrest 21 forward to bring the backrest frame 21 towards the seat frame 22, and once the two frames are brought sufficiently close (i.e. nearly parallel) to each other, the seat frame 22 will rotate together with the backrest frame 21 towards the lower part of the telescopic bar 10. This lower part of the telescopic bars 10 between the frame joint 24 and the front wheel 13 is also referred to as front leg, while the support structure 11 is also referred to a rear leg.

Figure 5 schematically shows a perspective view of part of the stroller frame I according to an embodiment. As can be seen from this figure, the support structures II are coupled to each other by an intermediate bar 51 and at the lower end meet each other due to their curved shape. Each of the support structures 11 is coupled to the telescopic bar 10 by means of a coupling member 52. Figure 6 shows a coupling member 52 in more detail. The a coupling member 52 comprises a hollow tubular shaped part 52A arranged to enclose the telescopic bar 10, and a coupling mechanism which is arranged in a housing 52B which forms an integrated part with the tubular shaped part 52A. At one side wall of the housing 52B a docket 54 is arranged to receive at least part of the coupling elements 23 of the chair 2. In this example the docket 54 has a U-shaped docket wall extending from the side wall of the housing 52B. The docket wall is arranged to as to slidably receive one of the coupling elements 23. Once inserted into the docket 54, the coupling element 23 (and thus the chair 2) is locked onto the stroller frame 1 by a locking mechanism arranged in the coupling member 52 when the chair is unfold. A handle 55 is arranged on the coupling member 52 to unlock the frame 1 so it can fold. By pressing the handle 55 a pin 56 is rotated. On this pin 56 two extensions are arranged which extend in a radial direction out of the pin. These extensions cooperate with blocking lips 82 (see also Figure 8) of the coupling elements 23. Only, when rotation of the pin 56 is possible, the handle 55 can be used in, and the frame 1 can fold.

By pushing the telescopic bars 10 down in folding position, pin 56 is rotated. On this pin 56 two extensions are arranged which extend in a radial direction out of the pin. These extensions cooperate with blocking lips 82 of the coupling elements 23. Only, when rotation of the pin 56 is possible, the telescopic bars 10 can slide down in folding position.

When the chair 2 is unfold the blocking lips 82 are blocking the pin 56 to rotate, and the telescopic bars 10 and the frame 1 cannot go in folding position.

When the telescopic bars 10 or the frame 1 is in folding position. The blocking lips 82 are blocked by the pin 56 to move, and the chair cannot unfold.

Figure 7A schematically shows a detailed view of the coupling member 52 with the frame joint 24 docketed. In Figure 7A that side of the frame joint 24 is shown, which in use faces the chair. Some elements of the frame joint 24 are left out so as to show the structure of the main part of the frame joint 24. The frame joint 24 comprises a disc shaped body with at the outer circumference a multitude of structures arranged in a ring, referred to as the outer ring 71. This outer ring 71 has at least one tapered notch 72 at an inner circumference. This notch 72 is arranged to receive (part of) a locker as will be explained in more detail later on.

At a central part, the frame joint 24 also comprises a structure forming a disc 73 and around that disc 73 a first ridge 80 and a second ridge 85 are arranged. These ridges 80 and 85 can be regarded as being part of an inner ring 74. As can be seen in Figure 7A, the first ridge 80 is thinner than the disc 73 while the second ridge 85 is as thick as the disc 73.

The inner ring 74 comprises at least one tapered notch 75 at an outer circumference. This notch 75 is formed between the two ridges 80, 85. The notch 75 is arranged to receive a further locker as will be explained in more detail later on. It is noted that in the embodiment shown in Figure 7A, a relatively large part of the inner ring 74 is empty space. This empty space can be regarded as being a large notch or groove in the inner ring 74, and as such is regarded here as being part of the inner ring 74. In Figure 7A a circular dashed line indicates the outer circumference of the defined inner ring 74. Figure 7B schematically shows a front view of the inner ring 74 of Figure 7A. A groove 104 is defined in the inner ring 74 see the inner dotted line. This groove 104 is a ring shaped groove and extends from one wall (see 125) of the ridge 85 to the other wall (see 129) of the ride 85 and passed the ridge 80. The function of the groove 104 and walls 129, 125 will be explained in e.g. Figures 12C.

Figure 8 shows a perspective view of the other side of the frame joint 24 together with the coupling element 23. The coupling element 23 comprises two lockers 81 which are arranged to lock the coupling element 23 to the docket 54 in pockets 54A shown in Figure 6. Furthermore, the coupling element 23 comprises two blocking lips 82 which are movably arranged in the coupling element 23 and block, in one of their two possible positions, a rotation of the pin 56 arranged in the housing 52B, see also Figure 6. The two blocking lips 82 are moved to one of their two possible positions by a transmission system (not shown in Figure 8) arranged in the coupling element 23.

Figure 9A shows a perspective view of a part of the backrest frame 21 which, in this embodiment, forms an integral part with a seat disc 91 and a backrest ring 92. Figure 9A also shows a backrest locker 93 which is arranged in a corridor 94 in the backrest ring 92. At the inner side, i.e. the side facing inward, the backrest rings 92 comprise a groove 128. This groove extends in a tangential direction but over less than 360 degrees. So the groove 128 has two outer ends, one of them is indicated with reference number 122.

Figure 9B shows a perspective view with cutout of a part of the frame joint 24 and the coupling element 23. At an inner circumference of the outer ring 71, a ridge 131 is arranged, which ridge comprises two sidewalls 134, 135. Once in the assembled state, the outer ring 71 will surround the backrest ring 92 shown in Figure 9A and the inner ring 74 will be arranged within the backrest ring 92. In the coupling element 23 a transmission 95 is movably arranged to cause the lockers 81 to move in opposite directions and out of the coupling element 23. If the transmission moves back towards the central axis 90 of the frame joint, the lockers 81 will be pulled back to each other by means of a helical spring 83.

Between the backrest ring 92 and the inner ring 74, a seat ring 96 is coaxially arranged. Figure 9C shows a perspective view of an embodiment of the seat ring 96 fixed to the seat frame 22. The seat ring 96 comprises a corridor 97 in which a seat locker 98 is movably arranged so that the seat locker 98 can move in a radial direction from and to the axis of rotation 90. In this example the seat locker 98, in a plane perpendicular to the axis of rotation 90, has a cross section shown two tapered outer ends and an intermediate rectangular part. Other cross sections are conceivable as will be elucidated with reference to Figure 34.

When placed in the corridor 97 of the seat ring 96 of Figure 9C, the locker 98 is guided by three walls formed by the seat ring 96, and a fourth wall not visible in Figure 9C. This fourth wall is formed by the surface 20 shown in Figure 7A which is the inner surface of the side wall of the joint 24. As can be seen in Figure 9C, one of the walls forming the corridor 97 comprises a tapered extension having two side walls 105 and 106. These side walls determine the range of the possible rotation of the seat disc 96 relative to the inner disc 71, and thus the range of the possible rotation of the seat frame 22 relative to the stroller frame 1.

At the outer circumference, the seat ring 96 comprises a ridge 89 which has an outer end 123. As such the ridge 89 forms an extension that falls into the groove 128 of the inner side backrest ring, see Figure 9A.

Figure 9D shows a side view of the backrest ring 92 according to an embodiment. In Figure 9D the dashed line 18 indicates a substantially tubular shaped element 18 arranged between element 91 and the front of the backrest ring 92. The element 18 comprises a tubular wall interrupted by two walls 119 and 120 extending in a direction having a radial component. The two walls 119, 120 function as limiters to limit a rotational movement of the backrest ring 92 relative to the outer ring 71 and thus the rotational movement of the backrest frame 21 relative to the stroller frame 1.

Figure 10 shows a cut out view of the frame joint 24 with the four rings 74, 96, 92 and 71 being assembled together. This total assembly enables a relative thin design (e.g. thinner than 20 mm) of the joint 24, resulting in a chair design that has a relatively small width. Typical values of the width of the chair 2 lie in the range of 25 cm - 30 cm, while the total width of the stroller including the stroller frame 1 may have a width of less than or equal to 40 cm. Such dimensions will fulfill the carry-on hand luggage requirements of most airline companies.

The backrest ring 92 and the seat ring 96 are arranged in between the outer ring 71 and the inner ring 74 from frame joint 24. For this reason the backrest ring 92 and the seat ring 96 are also referred to as intermediate rings 92, 96. Figure 10 also shows the seat locker 98 and the backrest locker 93 (in black). It is noted that in this example the seat ring 96 is hollow, and from Figure 10 it seems as if the seat ring 96 is built up of two rings, but functionally it is one integral part, as also can be seen from Figure 9C.

Now the functioning of the frame joint 24 will be explained with reference to some drawings showing different stages of the folding and unfolding of the chair 2.

Each of the Figures 11-22 are built up with an A, B and C section. Section A shows a side view of the stroller in a simplified way to shown the orientation of the backrest frame 21 and the seat frame 22. Section B of the drawings shows an open side view of the frame joint 24. Section C shows a schematic cross section of the frame joint 24, presented in a way wherein the X-direction of the C section represents the tangential direction of the physical structure shown in the corresponding section B.

Figure 11A shows a side view of the stroller with the chair 2 in a folded state, so the backrest 21 and the seat have nearly the same orientation. Figure 11B shows that in this situation, the seat locker 98 occupies (i.e. has entered with an outer end into) a notch 101 arranged in the inner circumference of the back rest ring 92. At the same time, the seat locker 96 occupies (i.e. has entered with an outer end into) a notch 102 arranged in the inner circumference of the back rest ring 92. In this state the backrest ring 92 and the seat ring are coupled to each other. They may rotate relative to the inner and outer ring 71, 74 from frame joint 24, but this can only be done together and not separately. In other words, the backrest frame 21 and the seat frame 22 are locked together in their rotational direction. As can be seen from Figure 11C, the inner ring 74 comprises two notches being notch 75 and notch 78. In between the notch 75 and notch 78 the inner ring 74 comprises a groove 104 through which two extensions 105, 106 of the seat ring 96 may move. It is noted that Figure 11C is a very simplified picture and that in the actual joint 24 shown in Figure 11B, has a more complex design.

As can be seen from Figure 11C, the outer ring 71 comprises a number of notches amongst which the already mentioned notch 72. A second notch 107 may be arranged next to notch 72. In between notch 107 and notch 72 a separator 108 is arranged separating the two notches 72, 107. In this example, three other notches 109, 110, 111 are arranged in the outer ring 71. The notches 109, 110, 111 are separated by separators 112 and 113. Reference numbers 115 and 116 seem to indicate a further notch and a separator but in fact represent a wider notch having a sloped surface, the surface increasing in a direction out of the plane of the paper when going from left to right in Figure 11C. The functioning of this slope will be discussed below in more detail.

In between the notch 109 and notch 107 the outer ring 71 comprises a groove 118 through which two extensions 119, 120 of the backrest ring 92 may move. Reference is made to the description of groove 104.

Figure 11C also shows that the backrest ring 92 and the seat ring 96 both comprise a further extension 122, 123 respectively. These further extensions 122 and 123 hook into each other and as such allow the backrest ring 92 to pull at the seat ring 96 and the other way around.

It is noted that in an alternative embodiment, the configuration of the rings can be a mirrored configuration, meaning that Figure 11C could be turned upside down. In such an embodiment, the functioning of the inner and outer ring are interchanged, and the notches, grooves and limitations in the inner ring as shown in Figure 11C are instead arranged in the outer ring and vice versa.

Figures 12A, 12B, 12C show the situation wherein the backrest 21 is rotated as indicated in Figure 12A. Figure 12C shows that now the backrest ring 92 will move to the right and pulls seat ring 96 to the right as well, see the arrows in Figure 12C.

This movement will be blocked due to the extension 106 meeting an outer end of the groove 104, formed by a wall of the ridge 85, see Figure 7B. This wall is also referred to stopper 125. Figure 12B shows the corresponding cross section of the joint 24 in this situation.

Figures 13A, 13B, 13C show the situation wherein the backrest 21 is rotated as indicated in Figure 13A. As shown in Figure 13A, the seat 22 stopped on the right position. Since the backrest frame 21 is further pulled up, the backrest ring 92 will be forced ‘to the right’ in Figure 13C, as indicated by the arrow. Now, due to this force, and due to the sloped walls of the notches 101, 102, the lockers 93 and 98 will move and will change automatically from position as indicated by the vertical arrows in Figure 13C.

Figures 14A, 14B, 14C show the situation wherein the backrest 21 is rotated as indicated in Figure 14A. The seat 22 will stay in place while the backrest 21 will further rotate. As a consequence the seat locker 98 will be pushed further into the notch 75 of the inner ring 74, and at the same time, the backrest locker 93 will move into notch 116. As mentioned above notches 115 and 116 are in fact one single notch having a sloped surface. The backrest locker 93 is not blocked by the notches 115, 116 but it will be displaced in the direction perpendicular to the paper towards the reader when viewing Figure 14C.

Figures 15A, 15B, 15C show the situation wherein the backrest 21 is in the fully upright position, as indicated in Figure 15A. The backrest locker 93 has glided over the sloped surface 115,116 until it clicks into the notch 72 locking the position, see Figure 15C. Figure 15B shows the corresponding cross section of the joint 24 in this situation.

Figures 16A, 16B, 16C show the situation wherein the backrest 21 is a semi reclined position, as indicated in Figure 16A. By activation of the recline button 26, see also Figure 2, the backrest 21 can be changed between fully upright to the semi reclined position. The backrest locker 93 has been pulled out of the notch 72 and clicks into the neighbouring notch 107 locking the position, which movement is indicated by a double sided arrow, see Figure 16C. Figure 16B shows the corresponding cross section of the joint 24 in this situation.

Once the user has operated the recline button 26 again, and pulls the backrest 21 downwards while keeping the recline button 26 pushed in until position notch 116, the backrest ring will rotate until the backrest frame 21 meets the seat frame 22, which state is shown in Figures 17A, 17B, 17C. After position of notch 116 the backrest ring can also rotate without using the recline button 26. Figure 17C shows that the backrest locker 93 meets a wall of the notch 115. Furthermore, the backrest ring 92 meets the extension 123 of the seat ring 96. An arrow indicates the direction of force applied to the backrest ring 92.

If the backrest frame and the seat frame are rotated further, the lockers 93, 98 will change automatically from position, as is shown in Figure 18C. Arrows in the Figure 18C indicate the movement of the different elements. The seat ring 96 will follow the backrest ring 92 during this stage of the folding. As can be seen from Figure 18C, the backrest locker is urged out of the notch 115, while the seat locker 98 is urged out of the notch 75. As can be seen from Figure 18C, both lockers 93, 98 move in a radial direction (in Figure 18C this is the Y direction), but they move in opposite directions. Figure 18A and 18B show the corresponding side views.

Figures 19A, 19B, 19C show the situation wherein the chair is completely folded and rotated in the plane of the telescopic bars 10. Figure 19C shows the positions of the rings and the lockers. It is noted that these positions are identical to those in Figure 11C, which showed the beginning of the unfolding process.

As mentioned above, the chair 2 can be removed from the stroller frame 1. Once removed from the stroller frame 2, the seat can be rotated in the horizontal plane by 180 degrees, and remounted onto the stroller frame. In this way a child can face the caretaker pushing the stroller. This configuration is also referred to as 'facing parent'. Figures 20A, 20B, 20C show the situation wherein the chair is in the facing parent configuration while being completely folded. The arrows indicate the directions in which the elements are rotated. Due to the lockers 93, 98 3, the backrest frame 21 will follow the seat frame 22 when pulled up.

Figures 21 A, 21B, 21C show the situation wherein the backrest frame and seat frame are further rotated to a substantially vertical position, see Figure 21A. The user may pull at the seat frame 22, as indicated by the arrow in Figure 21 A. Since in this stage the seat ring 96 and the backrest ring 92 are locked to each other, the backrest frame 21 will follow the rotation of the seat frame 22. The backrest frame 21 will stop on the fully upright position due to the fact that the extension 119 of the backrest ring 92 is blocked by the stopper 135, as is shown in Figure 21C. Figure 21B shows the corresponding side view of the open frame joint 24.

If the seat frame is rotated further, the backrest frame will not follow (it will stop on the fully upright position), and the chair will start to unfold. The beginning of this unfolding is shown in Figures 22A, 22B and 22C. As can be seen from Figure 22C, the lockers 93, 98 will automatically move into opposing radial directions, and into the notches 109 and 78 respectively.

The chair may be further unfolded by rotating downward the seat frame 22 as indicated in Figure 23A. Figure 23B shows the corresponding side view of the open joint. The seat frame 22 will stop on the right position due to the fact that the seat ring 96 is stopped from rotating by a stopper stopping the extension 105 and locker 98, see Figure 23C.

The frame joint enables the unfolding of the chair in a single rotational movement, wherein the backrest and the seat are both stopped from rotating further when being in their correct (i.e. their use) positions.

Figures 24A, 24B, 24C show the situation wherein the backrest 21 is a semi reclined position, as indicated in Figure 24A. By activation of the recline button 26, see also Figure 2, the backrest 21 can be changed between fully upright to the semi reclined and fully reclined position. The backrest locker 93 has been pulled out of the notch 109 and clicks into the neighbouring notch locking the position, which movement is indicated by a double sided arrow, see Figure 24C. In this embodiment, the backrest frame 21 can be fixated into three different orientations, due to the fact that the locker 93 can fall into three notches, see notches 109, 110 and 111. Figure 24B shows the corresponding cross section of the joint 24 in this situation. Not all notches are visible in Figure 24B.

Once the child has been removed from the chair, the seat frame 22 can be pulled up and rotated as indicated in Figure 25A. It is noted that no button needs to be pushed. Due to the force applied on the seat ring 96, which is transferred to the backrest ring 92 by extension 122, 123, the backrest locker 93 is urged out of the notch 110 and into the notch 102 arranged in the seat ring 96, see also Figure 25C.

If the seat frame 22 is rotated further, it will meet the backrest frame 22, and together they will be rotated as indicated in Figure 26A. Figure 26C shows that the lockers, 98 will change automatically from position. The backrest frame 21 and the seat frame 22 will both be unlocked from the inner and outer ring which are coupled to the stroller frame 2 via the coupling element 23, as was shown in Figure 7.

Figures 27A, 27B, 27C show the situation wherein the backrest 21 and the seat frame 22 are fully folded and brought in line with the plane of the telescopic bars 10. Figure 27 is in fact the same as Figure 20 but no forces are applied.

Figure 28 schematically shows parts of the backrest frame 21. Inside the backrest frame a cable 100 is arranged which at a first outer end 140 is coupled to the recline button 26 and at its other outer end is coupled to the opposite backrest locker 93. By pulling the cable 100, the backrest locker 93 is moved in a co-axial direction relative to the axis of rotation 90. In this way, the user can displace the backrest locker 93 by operating the recline button 26. It is noted that the recline button 26 could be arranged at another location in the backrest frame 21, for example at one of the sides of the backrest frame.

Figure 29 schematically shows a cut perspective view of a frame joint 24 and some parts of the chair. The frame joint 24 is cut in a plane through the axis of rotation 90. Figure 29 shows the outer ring 71, the backrest ring 92, the seat ring 96 and the inner ring 74 all being axially arranged around the axis of rotation 90. The four rings are arranged in the same plane perpendicular to the axis 90. This enables a very thin design of the joint 24. Figure 29 further shows that the backrest locker 93 is movable in a radial direction relative to the rotational axis 90, and also in a co-axial direction. The backrest locker 93 is moved in the radial direction due to a rotational movement of the backrest ring 92 relative to the seat ring 96 as was shown in Figure 12C, or relative to the outer ring 71, as was shown in Figure 18C.

The backrest locker 93 is moved in the co-axial direction due to a pulling force of the cable 100. Figure 29 also shows a spring 130 arranged behind the backrest locker 93 which pushed the locker 93 back against the backrest ring 92. The co-axial movement of the locker 93 enables the joint 24 to switch between different inclinations of the seat frame 22, see also Figure 16C.

Figure 30 shows a detailed side view of the joint 24 in a fully folded state of the chair 2. In that situation the coupling element 23 points in the same direction as the backrest frame 22 and the seat frame 21. Reference is also made to Figure 11A and 20A. In Figure 30 the backrest locker 93 is visible through a rectangular window, which seems to make the locker look rectangular, but also in this example the backrest locker 93 has the same shape (at least in the plane of view) as the seat locker 98.

The coupling element 23 comprises a transmission 95 that is movably arranged to cause the lockers 81 to move in opposite directions and out of the coupling element 23. In Figure 30 the backrest ring 92 is orientated in such a way that a tapered outer end of the transmission 95 has entered the notch 99 at the outer circumference of the backrest ring 92. Once the folded chair 2 is slightly rotated, the transmission is forced out of this notch 99. Figure 31 shows a detailed side view of the joint 24 in a nearly folded state of the chair 2. As compared to Figure 30, the coupling member 23 is slightly rotated relative to the backrest frame 22 and the seat frame 21. In that situation the transmission 95 is forced out of the notch 99 and moves as indicated by the arrow.

Due to this movement, the two lockers 81 which are arranged to lock the coupling element 23 to the docket 54 shown in Figure 6, are separated and will enter cavities 54A (also referred to as pockets 54A) in the docket walls shown in Figure 6. This will result in a locking of the chair relative to the stroller frame. So, only when a child is out of the chair, the chair can be folded, collapsed, and brought in line with the telescopic bars 10, and thus be uncoupled from the frame. A further embodiment is now described with reference to Figures 32A, 32B, 33A and 33B. In this embodiment, the frame joint comprises one locker instead of two. Furthermore, the above described notch 101 in the backrest ring 92 and the notch 75 are absent. The further embodiment can be folded and unfolded, a folded state being shown in Figure 20A. Once the user pulls up the seat 22, the backrest 21 will follow, see also Figure 21A, which is copied in Figure 32A. Figure 32B shows the schematic cross section of the fame joint. In this example, the backrest locker 93 has a different shape as compared to the previously described embodiment. The backrest locker 93 in Figure 32B has a substantially rectangular cross section with two beveled corners. So this embodiment of the locker 93 is non-symmetrical with reference to a radial line. The locker may be embodied by an elongated beam shaped body having at one of its side walls two sloped parts, making the two outer ends of the locker somewhat tapered or wedge shaped. In the example of Figure 32B it can be seen that three notches 109,110,111 have corresponding cross sections. The seat ring 96 comprises a notch 102 which has one sloped side wall. Once a force is applied by this sloped side wall, the locker 93 is urged out and moved towards the notch 109 in the outer ring 71. This force is a result of the user rotating the seat frame 22 further down while the backrest frame 21 will stay in its position shown in Figure 32A. As explained with reference to Figure 22C, the backrest frame 21 will stay in its position due to the fact that extension 119 arrived at the end 135 of the groove 118.

Figures 33A and 33b show the situation wherein the chair is folded wherein the seat frame 22 is rotated towards the backrest frame 21. The seat ring 96 will move to the left in Figure 33B and will push the backrest ring 92 to the left. This will cause the locker 93 from moving towards the axis of rotation indicated by the arrow in Figure 33B pointing down. As a consequence the backrest frame 21 is unlocked and can rotate together with the seat frame to the plane of the telescopic bars 10, to further fold the stroller.

Figure 34 shows some further possible examples of the cross section of the locker 93 in a plane rectangular to the axis of rotation 90. It is noted that the locker 93 can have a rectangular cross section in a plane defined by the axis of rotation. The locker 93 can have the same thickness as the rings 71, 92 or may be a little thinner. Typical values of the thickness th of locker 93 lie in the range of 10 mm - 35 mm. In case the locker 93 can be moved in the axial direction, e.g. by means of pulling cable 100. The locker may have a 3D configuration shown in Figure 35. As can be seen in Figure 35, the locker 93 comprises a connection point 148 for the cable 100 and two surfaces 149 to support locker 93 when it moves along the axis 90.The components of the frame joint 24 can all be made out of plastic by other materials are also possible, such as metal or aluminum.

It is noted that in the above, both the term “bars” and “tubes” are used. It is noted that a “tube” is regarded as a hollow bar, but that a “bar” as mentioned above does not necessarily need to be hollow. In some embodiments, the bars mentioned above could be homogenous (not hollow) or at least partly homogenous. Furthermore, the stroller frame 1 could have non-telescopic bars, having frame elements that are pivotably arranged, wherein folding the stroller frame is possible by pivoting the frame elements relative to each other.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.

In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

A folding chair (2) for a pram, the folding chair comprising: - a backrest frame (21); - a seat frame (22); - two coupling elements (23) for removably coupling the seat to the pram; - two frame connections (24) for rotatably connecting the coupling elements to the backrest frame and the seat frame, wherein the backrest frame and the seat frame can rotate about an axis of rotation (90) and wherein each of the frame connections (24) comprises: - a first ring ( 74) attached to one of the coupling elements and comprising two limiters (125, 129); - a second ring (71) attached to one of the coupling elements and comprising two limiters (134, 135) and at least one notch (109) on a circumference, characterized in that the folding chair further comprises: - a seat ring (96) attached to the seat frame (21) and arranged between the first and second ring, the seat ring comprising at least one notch (102) on a circumference; - a backrest ring (92) attached to the backrest frame and arranged between the seat ring and the second ring (71), the backrest ring comprising a passage (94) extending in a radial direction, and - a backrest lock (93) movably arranged in the passage (94) of the backrest ring (92), wherein the foldable seat (2) can be manually changed from a folded state to an unfolded state, by rotating the backrest frame and the seat frame.

The folding chair of claim 1, wherein the first ring (74) is an inner ring, coaxially arranged within the second ring, referred to as the outer ring (71), wherein the outer ring (71) on an inner circumference at least one notch (109), and wherein the at least one notch (102) is disposed in the seat ring on an outer periphery of the seat ring.

The folding chair according to any one of the preceding claims, wherein the backrest frame (21) and the seat frame (22) can rotate freely around the axis (90) in the folded state until the backrest ring (92) is blocked by one of the limiters (134, 135) while the seat ring can rotate further, whereby, as a result of this further rotation of the seat ring, the backrest lock is driven out of the notch (101) of the seat ring and into the notch (109) of the second ring, and wherein the backrest lock is secured in the notch (109) of the second ring, by a circumference of the seat ring (96).

The folding chair according to any of the preceding claims, wherein the seat ring (96) comprises a passage (97), and wherein the backrest ring (92) comprises at least one notch (101) on a circumference, each of the frame connections ( 24) includes a seat lock (98) movably mounted in the passage (97) of the seat ring (96).

The folding chair according to any one of the preceding claims, wherein the backrest lock (96) comprises a body with a body part which, at least in use, extends in the radial direction and has a cross-section in a plane perpendicular to the axis of rotation (90) which shows a cross-sectional center section and two tapered or wedge-shaped outer sections.

The folding chair of any one of the preceding claims, wherein the second ring (71) comprises at least one further notch (110, 111) disposed adjacent to the notch (109), wherein the backrest magnifier can be moved in a direction parallel to the axis of rotation and out of the notch (109), wherein a further rotation of the backrest frame causes the backrest lock to fall into one of the at least one further notches (110, 111).

The folding chair according to claim 6, wherein the backrest frame (21) comprises an adjustment mechanism for reclining the backrest from a first backrest orientation into a second backrest orientation, the adjustment mechanism including a backrest button (26) arranged in the backrest frame ( 21), and wherein activating the backrest button (26) will move the backrest lock (93).

The folding chair according to any of the preceding claims, wherein the frame connections (24) are disc-shaped, with a width w, with a value of preferably less than 20 mm.

A foldable pram, the foldable pram comprising: - a foldable seat (2) according to one of the preceding claims; - a foldable pram frame (1) comprising two couplings, each of the couplings being adapted to receive one of the coupling elements (23) to connect the foldable seat to the pram frame.

The foldable pram according to claim 9, wherein the pram frame comprises two telescopic rods (10) and two handles (55), each of the handles being mounted on one of the telescopic rods (10) and adapted to activate an unlocking mechanism so that folding of the pram frame is made possible, whereby the activation of the handles can be blocked by a blocking mechanism arranged in the coupling element (23) when the seat is folded.