EP3681783A2

EP3681783A2 - Device for transporting a child, and child seat

Info

Publication number: EP3681783A2
Application number: EP18855125.3A
Authority: EP
Inventors: Freek DRIESSEN
Original assignee: Mutsy BV
Current assignee: Mutsy World BV
Priority date: 2017-09-14
Filing date: 2018-09-12
Publication date: 2020-07-22
Also published as: CN111356624A; WO2019054863A2; NL2019551B1; WO2019054863A3

Abstract

The present invention relates to a device for transporting a child, such as a pushchair or buggy, and to a child seat suitable for such a device. The child seat is here coupled to the frame of the pushchair by means of an attaching part. According to the invention, the device comprises a locking device for keeping a first pivot point between back part and seat part locked relative to the attaching part during collapsing of the seat from the recumbent position to the sitting position, and for releasing this locking prior to or as a result of the collapsing of the seat from the sitting position to the collapsed position.

Description

Device for transporting a child, and child seat

The present invention relates to a device for transporting a child, such as a pushchair or buggy, and to a child seat suitable for such a device. An example of such a device is known from EP 2895376 Al.

The known device comprises a frame and a seat provided with a seat part and a back part, wherein the seat part and the back part can pivot relative to each other about a first pivot point for the purpose of collapsing and folding open the seat. The seat can here be collapsed from a recumbent position, via a sitting position to a collapsed position. The known device further comprises an attaching part for attaching the seat to the frame. The seat part is here pivotally connected to this attaching part.

In the known device the frame comprises an undercarriage with swivelling wheels on the front side and with fixedly disposed wheels on the rear side. On the front side the undercarriage is pivotally connected to an upper carriage. This upper carriage comprises a pair of lower tubes which are disposed parallel to each other and are pivotally coupled on an upper side thereof to respective upper tubes. A push bar is received telescopically in the upper tubes.

To collapse the known device the push bar is first placed in the lowermost position. The lower tubes and the upper tubes are then unlocked, whereby the upper tubes can be pivoted forward until they come to lie substantially parallel to the lower tubes. The undercarriage and the upper carriage are then unlocked, whereby the upper and lower tubes can be pivoted downward so that the upper carriage comes to lie substantially in the same plane as the undercarriage.

During the above stated collapsing the seat can remain coupled to the upper carriage. This is because the seat can be collapsed, whereby it does not obstruct said collapsing. This is possible in that the seat part and back part of the seat are pivotally connected at the first pivot point. More particularly, the known device comprises a four-bar linkage, wherein a first arm is formed by the attaching part. This part is pivotally connected on a first side to the back part and pivotally connected on a second side to a first end of a second arm. The second arm is pivotally connected at a second end to the seat part. The piece of the back part between the first pivot point and the pivot point between back part and attaching part forms a third arm, and the piece of the seat part between the first pivot point and the pivot point between the seat part and the second arm forms a fourth arm. As a result of the above stated four-bar linkage the seat part will move rearward during collapsing of the seat and the back part will come to lie substantially in the same plane as the seat part. The four-bar linkage has the advantage that the centre of gravity of the child relative to the undercarriage does not change, or hardly so, when the child is moved from a sitting position to a recumbent position and vice versa. In order to be able to transport the known device in for instance the boot of a car it is important that the device is able to collapse into the most compact package possible. It has been found that the compactness of the known device in collapsed state can be insufficient for some applications.

It is therefore an object of the present invention to provide a device which can be collapsed into a compact package.

This object is achieved with the device according to claim 1, which is characterized in that the device further comprises a locking device for keeping the first pivot point locked relative to the attaching part during collapsing of the seat from the recumbent position to the sitting position, and for releasing this locking prior to or as a result of the collapsing of the seat from the sitting position to the collapsed position.

According to the invention, as a result of or prior to the collapsing of the seat from the sitting position to the collapsed position, the first pivot point will at a given moment no longer be locked relative to the attaching part. This means that the position of the first pivot point is no longer fixed relative to the attaching part. The seat is however still pivotally connected to the attaching part. According to the invention, it is thus possible to pivot the at least partially collapsed seat as a whole relative to the attaching part. More particularly, the invention allows the seat to be pivoted relative to the attaching part, while the relative position of back part and seat part can be kept constant. It is hereby possible to better position the collapsed seat relative to the frame during collapsing of the device, whereby a more compact whole can be obtained.

In the device known from EP 2895376 Al the four-bar linkage causes the pivoting movement of the seat part relative to the attaching part to be coupled to the movement of the back part. It is thus not possible here to pivot the collapsed seat as a whole relative to the attaching part, whereby the intended compactness cannot be achieved to sufficient extent.

In addition to obtaining a more compact package after the collapsing, the present invention can result in a lighter device which is less complex. The seat can further be placed in a flatter position.

After releasing of the locking, the pivoting of the back part relative to the seat part is preferably mechanically uncoupled from the pivoting of the seat part relative to the attaching part.

The seat part is preferably pivotally connected at a second pivot point to the attaching part.

The second pivot point can here have a constant position relative to the attaching part during collapsing of the seat from the recumbent position to the collapsed position.

The frame can be provided with an undercarriage which is provided with wheels and an upper carriage pivotally coupled to this undercarriage, wherein the attaching part is coupled releasably to the upper carriage and wherein the frame can be collapsed by pivoting the upper carriage and undercarriage relative to each other. The undercarriage can here be formed by a pair of tubes, wherein swivel wheels are coupled to the undercarriage on the front side or rear side. The tubes can be disposed parallel to each other for a device which is provided with four wheels. It is however also possible, for a device which is provided with three wheels, for the tubes to approach each other in forward direction.

The upper carriage can comprise a pair of tubes or arms disposed parallel to each other. A telescopically adjustable push bar can be received in these tubes. It is further possible for the upper carriage to comprise a pair of lower tubes and a pair of upper tubes, wherein the upper tubes are pivotally coupled to the lower tubes and wherein the push bar is received in the upper tubes. The upper carriage can here be collapsed by pivoting the upper tubes toward the lower tubes.

The locking device can be configured to release the locking as a result of the collapsing of the seat from the sitting position to the collapsed position. In this embodiment the locking can be released in that the back part pivots relative to the seat part. This in contrast to an embodiment wherein the locking is released prior to the pivoting movement, for instance by a manual operation of the locking with an operating member. The locking device can be configured to keep the first pivot point locked relative to the attaching part during a first part of the collapsing from the sitting position to the collapsed position, and to release this locking during the remaining part of this collapsing. It is possible for the degree of locking to decrease gradually until a determined relative position of back part and seat part, wherein the locking is released, has been reached. This is for instance the case if there are two elements which engage in each other to greater or lesser extent and wherein the relative position of these elements changes during the pivoting of the back part relative to the seat part.

The locking device can comprise a first locking element coupled to the attaching part and a second locking element coupled to the seat, wherein the first locking element and the second locking element can lock relative to each other for the purpose of said locking of the first pivot point relative to the attaching part. The second locking element can here be pivotally coupled to the seat part and the second locking element can be configured to pivot as a result of the collapsing of the seat in order to thus release the locking between the first locking element and the second locking element.

In the above stated embodiment it is preferred for the device to comprise a resilient element, such as a torsion spring, for bringing the pivoting movement of the second locking element under spring tension, wherein the spring tension is chosen to make the second locking element rotate for the purpose of enabling locking with the first locking element.

To realize a mechanical coupling between the pivoting movement of the back part relative to the seat part, the back part can be provided with a support which defines a path on which the second locking element supports. During collapsing of the seat from the sitting position to the collapsed position an end of the second locking element will here follow the path and cause a rotation of the second locking element relative to the first locking element in order to break the locking between the first and second locking element. The support can for instance be formed as a stop edge arranged all around the first pivot point, wherein the distance between the first pivot point and the point at which the second locking element finds support against the stop edge progresses as a function of the angular position of the support point.

The seat part, at least when the seat is in the sitting position, the recumbent position or an intermediate position, extends in transverse direction above the attaching part so that it rests on the attaching part or touches it, whereby a downward movement of the seat relative to the attaching part is prevented. This mechanical construction can be seen as a downward locking. The engagement of the first locking element by the second locking element can further prevent an upward movement of the seat relative to the attaching part. This mechanical construction can be seen as an upward locking. The seat can be fixed relative to the attaching element by co-action of the downward and upward locking.

The second locking element can comprise an engaging part and a follower fixedly connected to the engaging part, wherein an end of the follower supports on the path and wherein the engaging part is configured to engage the first locking element. Because of the fixed connection between engaging part and follower, the movement of the follower defined by the path, more particularly the rotation of the follower, will result in a similar movement of the engaging part. The engaging part can comprise a hook, and wherein the first locking element comprises a shaft or pin extending in transverse direction.

The seat part can comprise a bottom part and side walls placed on either side of the bottom part and connected thereto. Each side wall is here connected on an upper side thereof to an end part. This end part extends in transverse direction so that it can support, at least in the sitting position, recumbent position or intermediate position of the seat, on the attaching part, and wherein the second locking element is pivotally connected to the end part. Each side wall can here be provided with a pair of side wall parts disposed parallel to each other, wherein the follower extends from the end part into a space between the pair of side wall parts and wherein the engaging part extends, at least when the seat is in the sitting position, recumbent position or intermediate position, from the end part toward the first locking element mounted in the attaching part. In this way the mechanism of the follower and the support is shielded from for instance children.

The engaging part can protrude on the underside of the end part for the purpose of engaging the first locking element. As described above, the first locking element can be embodied as a pin or shaft extending in transverse direction, i.e. substantially parallel to the shaft on which the wheels are mounted. Giving the attaching part a partially open form on an upper side enables the first locking element to be engaged by the engaging part. In the above the locking was released as a result of the relative pivoting movement of back part and seat part. It is however also possible for the device to comprise an operating member for operating the locking device for the purpose of said releasing of the locking. As an example the locking device can be configured to release the locking only when the seat is in the sitting position or in an at least partially collapsed position. Operating of the operating member preferably causes, by means of a mechanical coupling, the movement of the second locking element relative to the first locking element as a result of which the locking is released. In contrast to the above described embodiments wherein the locking was released as a result of the relative pivoting movement of back part and seat part, in this embodiment it is possible to opt to maintain the locking, even if the seat comes to lie in fully collapsed state.

The attaching part preferably comprises coupling means for coupling the attaching part to the frame. The coupling means can for instance be configured to realize a snap connection to the frame. As an example the coupling means can comprise a first coupling part which is connected to the frame, and more particularly to the upper carriage, and a second coupling part which is connected to the seat part. The first or second coupling part can here comprise a protrusion or pin which is under spring tension and which can engage in an opening or recess of the other of the first or second coupling part. By coupling the first and second coupling part the protrusion or the pin will enter the opening or recess, whereby the seat is locked to the frame. A further operating member can be provided for the purpose of moving the protrusion or the pin counter to the spring tension so that the seat to be removed from the frame.

The device can further be provided with a bumper bar which is pivotally connected at a third pivot point to the attaching part. The device can further comprise a first arm which is connected to the bumper bar or has a constant position relative to the bumper bar, a second bar which is pivotally connected at an end to the first arm and is pivotally connected at a second end to the back part at a distance from the first pivot point, wherein the positioning of the first arm and second arm is such that the bumper bar rotates in the same direction as the back part during collapsing of the seat. In this embodiment the movement of the bumper bar is mechanically coupled to the pivoting movement of the back part relative to the seat part. The bumper bar has a constant position relative to the first arm because the first arm is connected to the bumper bar directly or via intermediate non-pivoting elements.

It is preferred for the first and second arms to likewise extend in the space between the side wall parts for the purpose of shielding these parts. It is further preferred for the third pivot point and the second pivot point to be identical.

The device can be provided with a foot support mounted pivotally on the frame and having therein a recess for partially receiving the bumper bar. After the seat has been fully collapsed the bumper bar will have been received in the recess, whereby the device can be made even more compact.

According to a second aspect, the invention provides a child seat suitable for a device for transporting a child as described above. Such a child seat comprises a seat part and a back part, wherein the seat part and the back part can pivot relative to each other about a first pivot point for the purpose of collapsing and folding open the seat. The child seat further comprises an attaching part for attaching the seat to a frame of the above stated device. The seat part is here pivotally connected to the attaching part and the seat can be collapsed from a recumbent position, via a sitting position to a collapsed position.

The child seat according to the invention is characterized in that the child seat further comprises a locking device for keeping the first pivot point locked relative to the attaching part during collapsing of the seat from the recumbent position to the sitting position, and for releasing this locking prior to or as a result of the collapsing of the seat from the sitting position to the collapsed position. It will be apparent to the skilled person that the child seat according to the second aspect of the invention can be given an identical form to the seat of the above stated device for transporting a child.

The invention will be discussed in more detail hereinbelow with reference to the accompanying figures, wherein:

Figure 1 shows an overall perspective view of an embodiment of the device as according to the present invention;

Figure 2 shows only the child seat of figure 1 ;

Figure 3A shows a partially exploded view of the child seat, wherein figure 3B shows an associated schematic view of only the seat part;

Figure 4A shows a transverse view of the child seat in the sitting position and figure 4B an associated schematic view; and

Figure 5A shows a transverse view of the child seat in the collapsed position and figure 5B an associated schematic view.

Figure 1 shows an overall perspective view of an embodiment of the device as according to the present invention. A pushchair 1 comprising an undercarriage 2 and an upper carriage 3 is shown. Undercarriage 2 comprises a pair of arms 4 disposed parallel to each other and connected to each other by two transverse connections 5. Placed on the front side of undercarriage 2 are two swivel wheels 6, while two non-swivelling rear wheels 7 are placed on the rear side of undercarriage 2.

Upper carriage 3 comprises a pair of lower tubes 8 which are disposed parallel to each other and which are connected by means of a hinge 10 to upper tubes 9. A push bar 11 is received telescopically in these latter tubes. After unlocking by means of operating means (not shown) push bar 11 can be moved downward. Upper tubes 9 can then be unlocked relative to lower tubes 8 by further operating means (not shown). After unlocking, upper tubes 9 with push bar 11 received therein can be pushed forward until upper tubes 9 come to lie substantially in the same plane as lower tubes 8. After this the upper carriage 3 can be unlocked relative to undercarriage 2, if desired. After unlocking, upper carriage 3 can be moved downward by means of hinges 18 until undercarriage 2 and upper carriage 3 come to lie substantially in the same plane.

Pushchair 1 further comprises a seat 100 comprising a seat part 12 and a back part 14. Seat part 12 comprises a bottom part 121 which is connected on either side, preferably in integral manner, to a side wall 13, see figure 2. Back part 14 of child seat 100 is pivotally connected to seat part 12, as will be further elucidated below. In addition to seat part 12 and back part 14, child seat 100 comprises an attaching part 15 with which child seat 100 is coupled to lower tubes 8.

In the above stated collapsing of the frame by means of rotating/pivoting upper tubes 9 toward lower tubes 8 and then rotating upper carriage 3 downward child seat 100 must not have a blocking effect. As a result, child seat 100 can be collapsed, as will be elucidated below, prior to the collapsing of pushchair 1.

Pushchair 1 also comprises a bumper bar 16 and a leg support 17. As will be elucidated below, bumper bar 16 can pivot relative to attaching part 15.

Figure 2 shows only child seat 100 in perspective view. It is visible here that side walls 13 of seat part 12 each comprise a pair of side wall parts 130, 131 which are placed at a mutual distance. Side walls 13 further each comprise an end part 133.

Back part 14 can pivot relative to seat part 12 about first pivot point 132. Bumper bar 16 can pivot relative to attaching part 15 about a second pivot point 161. At pivot point 161 child seat 100 is also pivotally connected as a whole to attaching part 15. Rotation of leg support 17 is possible by means of hinge 171.

Figure 3 A shows a partially exploded view of child seat 100. Figure 3B shows an associated schematic view.

It can be seen in figure 3 A that a toothing 136 which can co-act with a toothing 142 in back part 14 is accommodated in the space between side wall parts 130, 131. Also visible in the space between side wall parts 130, 131 is a bush 137, which bush can co-act with a bush 141 in back part 14. It is thus for instance possible for a rivet or other type of pin to be placed through an opening in side wall 13 at the position of first pivot point 132 for coupling to bushes 137, 141, so that back part 14 can be pivoted relative to seat part 12. Back part 14 can be placed in a desired position and locked relative to seat part 12 by operating means (not shown) which co-act with toothings 136, 142. Such an adjusting option is known from the prior art and therefore requires no further explanation. Attaching part 15 comprises two openings 151, 152 through which pins 1511, 1521 are inserted. The pin inserted through opening 152 is here accessible on the upper side of attaching part 15.

Figure 3 A further shows that a second locking element 134 is accommodated in the space between side wall parts 130, 131. This element is shown in more detail in figure 3B. Second locking element 134 comprises a follower 1341, here formed as a finger, and an engaging part 1342 connected fixedly to follower 1341. Second locking element 134 is received pivotally in end part 133 at the position of pivot point 135.

As shown in figures 3 A and 3B end part 133 extends in transverse direction so that it can support on attaching part 15. It can be seen in figure 3A that second locking element 134 protrudes from end part 133 on the underside. More particularly, engaging part 1342 extends outside the space between side wall parts 130, 131. Engaging part 1342 will here, at least when child seat 100 is in the sitting position, engage pin 1521 which is placed in attaching part 15 at the position of opening 152. Pin 1521 can be referred to as first locking element. Because of this locking between first locking element 1521 and second locking element 134, child seat 100 cannot move upward. This is because, as shown in figure 3B, engaging part 1342 engages first locking element 1521 from an underside of this element. Child seat 100 can however not move downward either because end part 133 rests on attaching part 15.

Follower 1341 extends between side wall parts 130, 131 and supports on a stop edge 143 in back part 14. This is shown in further detail in figures 4A and 5 A.

Figure 3 A further shows that a part 164 protrudes from side wall 13. This part is received in a slot 163 of a bumper bar adapter 162. Bumper bar 16 can be placed releasably in this adapter.

End part 133 comprises a first part 1331 and a second part 1332 which can be coupled to each other. Part 1331 comprises here a bush 1333. First part 1331, second part 1332, side wall part 130 and side wall part 131 are fixedly connected to each other. Seat 100 is pivotally coupled to attaching part 15 by means of a pin 1334 at the position of second pivot point 161. Adapter 162 can further also pivot about second pivot point 161. This movement is however coupled to the movement of back part 14 by means of a bar linkage, which will be elucidated below.

Bumper bar 16 is connected to a first arm 165, see figure 3B. The relative position between first arm 165 and bumper bar 16 is here constant. At the end of first arm 165 a second arm 167 is pivotally connected at pivot point 166. At another end, second arm 167 is pivotally connected to back part 14 at pivot point 168.

Because of the coupling by means of first arm 165 and second arm 167, bumper bar 16 will pivot as a result of a pivoting movement of back part 14 relative to seat part 12. With a suitable placing and dimensioning of first arm 165 and second arm 167 it can be achieved that bumper bar 16 moves rearward when child seat 100 is placed in the recumbent position and moves forward when child seat 100 is collapsed. More particularly, it can be achieved that bumper bar 16 is at least partially received in a recess (not shown) of leg support 17 when seat 100 is fully collapsed. It is hereby not necessary to unlock bumper bar 16 separately so that it can be pivoted. The automatic adjustment of the position of bumper bar 16 in a change in position of seat 100 is further convenient for the user.

Figure 4A shows child seat 100 in transverse view, wherein side wall part 131 is not shown for the sake of clarity. In the shown sitting position, which is shown in perspective in figure 4B, follower 1341 supports on stop edge 143, which is formed in or coupled fixedly to back part 14. Stop edge 143 is here preferably placed concentrically around first pivot point 132 and bush 141.

Figure 4A shows that when back part 14 pivots forward, follower 1341 comes into contact with stop edge 143 at a position situated increasingly further away from first pivot point 132 and bush 141. Follower 1341 and engaging element 1342 will hereby rotate, and at a given moment engaging element 1342 will no longer engage pin 1521 which is placed through opening 152. The whole seat 100 can hereby pivot relative to attaching part 15 about second pivot point 161. This is shown in figures 5 A and 5B. Figure 5 A shows in particular that follower 1341 engages stop edge 143 at a position lying further away from bush 141 than shown in figure 3 A.

Engaging part 1342 is placed under spring tension by means of a torsion spring so that this urges engaging part 1342 to rotate in clockwise direction in figure 4A.

As shown in figures 4-5, the collapsing of the child seat according to an aspect of the present invention can be divided into a first part and a second part. During the first part, i.e. during movement from the recumbent position to the sitting position, both the first and the second pivot point are locked relative to the attaching part. During the second part, for instance from a position between the sitting position and the fully collapsed position to the collapsed position, only the second pivot point is locked relative to the attaching part. The whole seat can hereby turn about the second pivot point, whereby the seat can be moved further toward the front side of the pushchair and a more compact whole of the collapsed pushchair can be obtained.

The locking shown in the figures between the first and second locking element can also be released by operating an operating member (not shown). In such an embodiment the stop edge as shown in figure 4A can be omitted.

The invention has been discussed in the foregoing on the basis of embodiments of the invention. It will be apparent to the skilled person that the scope of protection of the application is not limited to these embodiments, but that various changes are possible without departing from the scope of protection defined by the appended claims. 1 Pushchair

2 Undercarriage

3 Upper carriage

4 Parallel arm undercarriage

5 Transverse connection undercarriage

6 Swivel wheel

7 Rear wheel

8 Lower tube

9 Upper tube

10 Hinge

11 Push bar

12 Seat part

13 Side wall seat

14 Back part

15 Attaching part

16 Bumper bar

17 Leg support

18 Hinge undercarriage

100 Seat

121 B ottom part seat

130 Inner side wall part

131 Outer side wall part

132 First pivot point

133 End part

134 Second locking element

135 Hinge second locking element 136 Toothing

137 Bush

141 Bush

142 Toothing

143 Stop edge

151 Opening end part

152 Opening end part 161 Second pivot point

162 Bumper bar adapter

163 Slot

164 Protruding part

165 First arm

166 Hinge arm

167 Second arm

168 Hinge arm

171 Hinge leg support

1331 Part end part

1332 Part end part

1333 Bush

1334 Pin

1341 Follower

1342 Engaging part 1551 Pin

1521 Pin

Claims

1. Device for transporting a child, such as a pushchair or buggy, comprising:

a frame;

a seat provided with a seat part and back part, wherein the seat part and back part can pivot relative to each other about a first pivot point for the purpose of collapsing and folding open the seat;

an attaching part for attaching the seat to the frame;

wherein the seat part is pivotally connected to the attaching part;

wherein the seat can be collapsed from a recumbent position, via a sitting position to a collapsed position;

characterized in that the device further comprises a locking device for keeping the first pivot point locked relative to the attaching part during collapsing of the seat from the recumbent position to the sitting position, and for releasing this locking prior to or as a result of the collapsing of the seat from the sitting position to the collapsed position.

2. Device according to claim 1 , wherein, after releasing of the locking, the pivoting of the back part relative to the seat part is mechanically uncoupled from the pivoting of the seat part relative to the attaching part.

3. Device according to claim 1 or 2, wherein the seat part is pivotally connected at a second pivot point to the attaching part.

4. Device according to claim 3, wherein the second pivot point has a constant position relative to the attaching part during collapsing of the seat from the recumbent position to the collapsed position.

5. Device according to any one of the foregoing claims, wherein the frame comprises an undercarriage which is provided with wheels and an upper carriage pivotally coupled to this undercarriage, wherein the attaching part is coupled releasably to the upper carriage and wherein the frame can be collapsed by pivoting the upper carriage and undercarriage relative to each other.

6. Device according to any one of the foregoing claims, wherein the locking device is configured to release the locking as a result of the collapsing of the seat from the sitting position to the collapsed position.

7. Device according to claim 6, wherein the locking device is configured to keep the first pivot point locked relative to the attaching part during a first part of the collapsing from the sitting position to the collapsed position, and to release this locking during the remaining part of this collapsing.

8. Device according to claim 6 or 7, wherein the locking device comprises a first locking element coupled to the attaching part and a second locking element coupled to the seat, wherein the first locking element and the second locking element can lock relative to each other for the purpose of said locking of the first pivot point relative to the attaching part.

9. Device according to claim 8, wherein the second locking element is pivotally coupled to the seat part and wherein the second locking element is configured to pivot as a result of the collapsing of the seat in order to thus release the locking between the first locking element and the second locking element.

10. Device according to claim 9, comprising a resilient element, such as a torsion spring, for bringing the pivoting movement of the second locking element under spring tension, wherein the spring tension is chosen to make the second locking element rotate for the purpose of enabling locking with the first locking element.

11. Device according to claim 9 or 10, wherein the back part comprises a support which defines a path on which the second locking element supports, wherein during collapsing of the seat from the sitting position to the collapsed position an end of the second locking element follows the path and causes a rotation of the second locking element relative to the first locking element in order to break the locking between the first and second locking element.

12. Device according to claim 11, wherein the support is formed as a stop edge arranged all around the first pivot point, wherein the distance between the first pivot point and a point at which the second locking element finds support against the stop edge progresses as a function of the angular position of the support point.

13. Device according to any one of the claims 8-12, wherein the seat part, at least when the seat is in the sitting position, the recumbent position or an intermediate position, extends in transverse direction above the attaching part and rests on the attaching part or touches it, whereby a downward movement of the seat relative to the attaching part is prevented.

14. Device according to claim 13 and claim 11 or 12, wherein the engagement of the first locking element by the second locking element prevents an upward movement of the seat relative to the attaching part.

15. Device according to claim 14, wherein the second locking element comprises an engaging part and a follower fixedly connected to the engaging part, wherein an end of the follower supports on the path and wherein the engaging part is configured to engage the first locking element.

16. Device according to claim 15, wherein the engaging part comprises a hook, and wherein the first locking element comprises a shaft or pin extending in transverse direction.

17. Device according to claim 15 or 16, wherein the seat part comprises:

a bottom part;

side walls placed on either side of the bottom part and connected thereto, wherein each side wall is connected on an upper side thereof to an end part;

wherein the end part extends in transverse direction so that it can support, at least in the sitting position, recumbent position or intermediate position of the seat, on the attaching part, and wherein the second locking element is pivotally connected to the end part.

18. Device according to claim 17, wherein each side wall is provided with a pair of side wall parts disposed parallel to each other, wherein the follower extends from the end part into a space between the pair of side wall parts and wherein the engaging part extends, at least when the seat is in the sitting position, recumbent position or intermediate position, from the end part toward the first locking element mounted in the attaching part.

19. Device according to any one of the claims 1-10, comprising an operating member for operating the locking device for the purpose of said releasing of the locking.

20. Device according to claim 19, wherein operating of the operating member causes, by means of a mechanical coupling, the movement of the second locking element relative to the first locking element as a result of which the locking is released.

21. Device according to any one of the foregoing claims, wherein the attaching part comprises coupling means for coupling the attaching part to the frame.

22. Device according to any one of the foregoing claims, further comprising a bumper bar which is pivotally connected at a third pivot point to the attaching part, the device further comprising a first arm which is connected to the bumper bar or has a constant position relative to the bumper bar, a second bar which is pivotally connected at an end to the first arm and is pivotally connected at a second end to the back part at a distance from the first pivot point, wherein the positioning of the first arm and second arm is such that the bumper bar rotates in the same direction as the back part during collapsing of the seat.

23. Device according to claim 22 and any one of the claims 17-18, wherein the first and second arms extend in the space between the side wall parts.

24. Device according to claim 22 or 23, wherein the third pivot point and the second pivot point are identical.

25. Device according to any one of the claims 22-24, further comprising a foot support mounted pivotally on the frame and having therein a recess for partially receiving the bumper bar.

26. Child seat suitable for a device for transporting a child as defined in any one of the foregoing claims, comprising:

a seat part and back part, wherein the seat part and back part can pivot relative to each other about a first pivot point for the purpose of collapsing and folding open the seat;

an attaching part for attaching the seat to a frame of the device;

wherein the seat part is pivotally connected to the attaching part;

characterized in that the child seat further comprises a locking device for keeping the first pivot point locked relative to the attaching part during collapsing of the seat from the recumbent position to the sitting position, and for releasing this locking prior to or as a result of the collapsing of the seat from the sitting position to the collapsed position.

27. Child seat according to claim 26, wherein the seat is embodied as defined in any one of the claims 1-25.