EP1551685A1

EP1551685A1 - Child's pushchair comprising steering wheel-locking means

Info

Publication number: EP1551685A1
Application number: EP03752848A
Authority: EP
Inventors: Damiano Marella; Vincent Truong
Original assignee: Ampafrance SA
Current assignee: Dorel France SAS
Priority date: 2002-05-21
Filing date: 2003-05-21
Publication date: 2005-07-13
Also published as: WO2003097426A1; FR2839935B1; CA2486861A1; FR2839935A1; AU2003249413A1

Abstract

The invention relates to a child's pushchair consisting of: at least one front steering assembly (16) comprising a fixed part which is solidly connected to the frame (15) of the pushchair and a mobile part which can rotate in relation to said fixed part along a first essentially vertical axis of rotation, said assembly bearing at least one wheel; and at least one rigid element which is mounted to the aforementioned fixed part, which moves in an essentially vertical manner and which co-operates with a housing provided for said purpose in the above-mentioned mobile part. In this way, means for locking/unlocking the rotation of the mobile part are formed in order to secure the mobile part with the fixed part in a central position in which the wheel or wheels are parallel to the rolling axis of the pushchair.

Description

Baby stroller fitted with directional wheel locking means.

The field of the invention is that of childcare, and more specifically baby cars (hereinafter called "strollers", this term encompassing here all childcare devices provided with wheels and allowing the transport of one or more children). More precisely still, the invention relates to the implementation of efficient rolling means on strollers.

Strollers most often have four wheels, or wheel blocks, mounted respectively at the end of legs of the stroller chassis, or at the ends of a transverse axis mounted to rotate freely on the chassis, depending in particular on the folding mode selected.

To improve the comfort of use, front wheels have been proposed which are mounted to rotate freely on a vertical axis, so that they are pivotable and thus facilitate changes of direction. In practice, these mechanisms are not always effective, and means are provided for locking each wheel in a fixed position. The implementation of these means is not easy, since it is necessary to bend down in front of each front wheel, and the latter are generally dirty ...

Consequently, users leave the wheels permanently in a fixed position (or in a free position), and do not take advantage of the advantages offered by the choice between the two positions, depending on the terrain.

It will also be noted that the free position, if it is pleasant on regular ground, poses problems as soon as one wants to climb a step or a sidewalk, or make a reverse. They then tend to go awry and block the progress of the stroller.

Three-wheeled strollers have also been developed, having a single front wheel, mounted in the central position, on a fork of the chassis. In this case, it seems a priori not possible to mount the free front wheel in pivoting, for obvious reasons of efficiency and safety (the wheel can for example be put at right angles and block the stroller). Three-wheeled strollers have therefore always a non-directional front wheel.

The invention particularly aims to overcome these drawbacks of the state of the art.

More specifically, an objective of the invention is to provide a stroller for children equipped with efficient directional wheels and easy to implement.

In particular, the invention aims to provide such a stroller, having good qualities of stability, steering control, rolling ...

A particular objective of the invention is to provide such a stroller, having a front wheel (or, according to the invention, a block of wheels) mounted in the central position.

Another object of the invention is to provide such a stroller, having good qualities of comfort and ergonomics, both for the child transported and for the person pushing the stroller.

A particular objective of the invention is also to provide such a stroller, which is adapted and / or adaptable to different types of terrain and situation (steps, reverse ...), in a simple and effective manner.

Yet another objective of the invention is to provide such a stroller, allowing a simple, effective and ergonomic action on the directional wheels. These objectives, as well as others which will appear subsequently, are achieved using a stroller for children, comprising according to the invention at least one directional front assembly, comprising a fixed part, integral with the chassis of said stroller , and a part movable in rotation relative to said fixed part, along a first substantially vertical axis of rotation, and carrying at least one wheel, and at least one rigid element mounted on said fixed part, movable substantially vertically and cooperating with a housing provided for this purpose in said movable part, forming means for locking / unlocking the rotation of said movable part, provided for securing the latter with said fixed part in a middle position, in which said wheel or wheels are parallel to the axis of rolling said stroller, thereby obtaining a stroller efficient, when driving and changing direction, and comfortable, based on a completely new approach to the front axle.

Advantageously, said fixed part is suspended at the forward-facing end of at least one extension of said chassis, and said wheel or wheels are carried by an element integral with said movable part extending along a second axis substantially horizontal, offset towards the rear of said stroller relative to said first axis.

In forward travel, the distance projected between these two axes improves driving comfort. Preferably, said fixed part and said movable part are secured to one another using an axial fixing means extending along said first axis of rotation.

It can for example be a shouldered screw, or a pin.

Advantageously, the stroller comprises suspension means mounted between said chassis and said fixed part. These suspension means can in particular comprise at least one spring mounted so that said fixed part, said spring or springs and the end of said chassis carrying said fixed part define a suspension triangle.

According to another advantageous aspect of the invention, the stroller comprises means for locking / unlocking the rotation of said movable part, securing the latter with said fixed part in a middle position, in which said wheel or wheels are parallel to the rolling axis of said stroller.

Said locking / unlocking means can thus advantageously comprise a rigid element (for example a pin, or plunger) mounted on said fixed part and cooperating with a housing provided for this purpose in said movable part.

According to an advantageous characteristic, said rigid element has a conical or frustoconical shape. This makes it easier to guide and / or take up play in the rigid element. Preferably, said rigid element cooperates with a spring of compression tending to bring it into its locked position, when the locked position is selected.

According to an advantageous characteristic, said locking / unlocking means are controlled remotely, using control means.

Preferably, said control means comprise a lever or a control button mounted on the handlebars of said stroller. Said control lever can in particular be mounted on a control block also comprising a brake control. Advantageously, said locking / unlocking means are actuated by cable.

In this case, preferably, said rigid element is mounted at the end of said cable, and in that said compression spring is mounted on said cable, between said rigid element and a stop. In particular, said control means can act on the distance between said stop and the distal end of said rigid element.

According to another advantageous aspect of the invention, said movable part is movable in rotation relative to said fixed part over a predetermined angular range relative to the axis of travel of said stroller. Said angular range is preferably symmetrical with respect to the rolling axis, and for example of the order of 20 to 35 ° on each side of said rolling axis.

According to yet another advantageous aspect of the invention, said front axle comprises return means tending to bring said movable part back to a middle position, in which the said wheel or wheels are parallel to the axis of travel of said stroller.

Advantageously, said return means comprise a torsion spring mounted on said fixed part.

According to another advantageous characteristic of the invention, said front axle comprises means intended to facilitate the movement of said movable part with respect to said fixed part. Said means intended to facilitate movement can in particular comprise at least one ball.

Advantageously, said means intended to facilitate movement comprise at least three balls, giving a planar support. Preferably, each of said balls is housed in a barrel with a spherical base formed in said fixed part (respectively said mobile part) and circulates in a ball path of hemispherical section in said mobile part (respectively said fixed part).

According to a first advantageous embodiment of the invention, said front assembly forms a suspended front axle.

According to a second advantageous embodiment of the invention, said stroller comprises two wheels or wheel blocks extending respectively in the extension of two front stretchers, and each provided with said locking means. According to a third advantageous embodiment of the invention, the stroller comprises a single wheel or block of front wheels, mounted in the extension of a first directional fork.

In this case, said wheel or said wheel block is preferably mounted on a second fork, movable in rotation about a horizontal axis with respect to said first fork, and in that it has suspension means between said first and second forks .

Other characteristics and advantages of the invention will appear more clearly on reading the following description of preferred embodiments of the invention, given by way of simple illustrative and nonlimiting examples, and of the appended drawings among which:

- Figure 1 shows a block diagram of a first embodiment of a stroller implementing a front axle according to the invention;

- Figure 2 illustrates in more detail the front axle and the front end of the stroller of Figure 1; - Figure 3 is a view of the movable part of the front axle of Figure 2;

- Figure 4 is a view of the fixed part of the front axle of Figure 2;

- Figure 5 shows the front axle locking pin of Figure 2;

- Figure 6 illustrates the control handle of the pin of Figure 5 and the braking means;

- Figures 7A to 7C schematically illustrate some alternative embodiments of the invention;

- Figure 8 shows a second embodiment of a stroller according to the invention, having 4 wheels; - Figure 9 is a simplified sectional view of the locking means for each front wheel of the stroller of Figure 8;

- Figure 10 shows the front part of a 3-wheeled stroller, according to another embodiment of the invention;

- Figure 11 is a sectional view of the connecting means of the wheel and the chassis of Figure 10;

- Figure 12 shows, in section, the locking means of the stroller of Figure 10. The invention therefore relates to a new approach to locking the (or the) wheel (s) before a stroller. Figure 1 shows a block diagram of a first embodiment of such a stroller, implementing a suspended front axle (this diagram being deliberately simplified, and not to scale, the suspended axle, in particular, being of size enlarged compared to the rest of the stroller), conventionally comprising a foldable frame 11, carrying a hammock 12 (or if necessary another device which can receive one or more children). The chassis 11 receives two rear wheels 13, mounted on an axle 14.

At the front, the chassis 11 has a fork 15 (or a single element, corresponding to the junction of the two branches of the fork). According to the invention, a front axle 16 is mounted suspended from the end of this fork 15. This front axle 16, illustrated in more detail in FIG. 2, is formed of two parts: a fixed part 21 secured to the chassis 11, and a movable part 22, relative to the fixed part 21.

The fixed parts 21 and mobile 22 form a whole (the front axle). The mobility of the mobile part 22 takes place with respect to a substantially vertical axis 23, so that the front wheel (s) can pivot, relative to the chassis 11.

It will be noted that the term "fixed" applied to the fixed part 21 relates to this rotation relative to the axis 23. This fixed part 21 remains however slightly mobile relative to the chassis, to ensure a suspension function. The fixed part 21 is therefore suspended from the fork 15 by a horizontal axis

24, so as to form, with one (or more) suspension element such as a spring 25, a suspension triangle.

The movable part 22 is mounted in pivot connection with the fixed part 21, using a shouldered screw controlling the tightening of the two parts. In the case of a single wheel, this can be mounted directly on the mobile part 22.

In the case of a block of two wheels, this has a vertical axis offset from another horizontal axis on which the wheels are mounted. The vertical axis is housed, to be secured there, in a housing 26 provided for this purpose in the movable part 22. In forward travel, the distance projected between these two axes improves driving comfort, by centering the two front wheels. in the direction of travel.

On the other hand, in reverse, this distance appreciably deteriorates driving comfort, the front wheels taking any position, and / or locking in one of their extreme positions (25 ° relative to the direction of travel, as will appear more clearly thereafter).

This problem is resolved by providing means for locking the front axle in a fixed position.

We have seen that this principle was known in itself. However, it is impractical in its known form. According to a particular aspect of the invention, provision is therefore made for controlling these offset locking means on the handlebars. The locking means are illustrated in FIG. 5. A pin 51 is mounted at the end of a cable, circulating in a sheath 52, with a compression spring 53. This assembly is assembled on the fixed part 21. The sheath 52 abuts against a ring 54, against which the spring 53 also rests. The remote control makes it possible to vary the length of the cable and therefore the length L of the pin (depending on whether the spring 53 is or is not compressed).

In a first position, the pin 51 (or plunger), which extends vertically, does not act (the spring being compressed). In a second position

(the spring pushing the pin back), the latter comes to plunge into a housing provided for this purpose in the mobile part 22. The fixed and mobile parts are then secured, and the steering is blocked.

Of course, the housing is positioned so that the wheels are straight (parallel to the rear wheels). If the pin 51 is not opposite this housing (that is to say if the wheels are not straight) during locking, the compression spring 53 acts on the pin so that it ensures the locking as soon as the train passes into its upright position. The return means described below facilitate this operation.

An embodiment of the control of these locking means is illustrated in FIG. 6. A single control block 61 groups together a braking control 62 (known per se) and the locking control 63, which can take two stable positions PI and P2 , corresponding to the two positions of the pin 51.

The lever 63 acts on the cable 64, via reduction means 65 pulling or releasing the cable 64.

FIG. 3 illustrates the mobile part 22. In this embodiment, means 31 and 32 for receiving the axis of the wheels are provided (it could also be suspended).

Note the presence of the housing 33 provided to receive the plunger 51, and a path 34 for guiding the latter as long as the wheels are not straight.

There are also ball tracks 35, 36, and 37, of hemispherical section, cooperating with balls mounted in the fixed part 21. Figure 4 illustrates this fixed part 21. As already mentioned, the front axle is pivotable relative to a vertical axis. In order to limit the forces and the noises due to the friction between the plates, 4 (for example) balls 41 are provided,

42, 43, 44, housed in drums 45, 46, 47, 48 with a spherical base. This gives a rolling without sliding between the two plates.

These four balls, which have, for example, a diameter of 8 mm, will therefore act as four point connections, giving plane support (with a degree of hyperstatism).

The ball paths 35 to 37 already mentioned make it possible not to mark the mobile part 22 with the imprint of the balls. It is noted that these paths are limited, so that the rotation is limited over a determined range on either side of the rest position (straight wheels), for example 25 ° on each side.

Furthermore, the fixed part 21 carries a torsion spring 49, tending to return the mobile part 22 to its upright position (front wheel (s) in the same direction as the rear wheels).

The ends 491, 492 of this spring come to bear against the stops 391, 392 (Figure 3) provided for this purpose.

Thus, without handling the product, the front axle returns to the upright position as soon as it is relieved (the front wheels no longer touching the ground), for example, to climb a sidewalk, or back up. This also facilitates the locking operations described above.

The invention can of course be implemented in many other forms, without departing from the scope of the invention. By way of example, FIGS. 7A to 7C schematically illustrate different mounting variants of the wheels 71 and of the connection of the front axle 72 with the chassis 73.

In addition, the methods of mounting, fixing and implementing the various components may vary, depending on the needs and the technical solutions available. Finally, the various aspects improving the general principle of the invention (return spring, remote control of the plunger, balls ...) are of course only advantageous options, but not compulsory.

According to a second embodiment, the invention can be implemented on a stroller provided with 4 wheels, or wheel blocks, and having two front stretchers at the end of which are provided directional wheels (wheel blocks).

Figure 8 is an example of such a stroller, viewed from the side. On each side extends a stretcher 81, on which a pusher 82 can slide, during folding. At the lower end of the stretcher is mounted a wheel 83 which is directional.

For this, there is provided, as illustrated in the sectional view of FIG. 9, a fixed part 91, integral with the stretcher 81, and a part movable in rotation 92 relative to this fixed part 84. The wheel 83 is mounted on this movable part 92.

According to the same principle as described above, the fixed part carries a pin 93, movable in translation vertically. In the locked position, the pin 93 fits into a housing 94 provided for this purpose in the mobile part 92. The fixed and mobile parts are then secured, and the wheel is no longer directional.

When the pin 93 is raised (position illustrated in FIG. 9), the movable part 92 can on the other hand freely rotate around the axis 95 connecting the two parts.

According to the same approach as above, the control of the pin 93 is preferably remote, and actuated by cable 97, for example from the pusher. Return means 96 act on the pin, tending to return it to the locked position, when the actuating cable is relaxed. Of course, in the case of such a 4-wheeled stroller, symmetrical means must be provided on each side. A specific actuation can be provided for each side, for example in the form of two sliding buttons provided on each of the pushers. It is also possible to carry out centralized control, actuating the two locking means simultaneously. In FIG. 10, which is a view of the front part of a three-wheeled stroller, there is shown a third embodiment of the invention.

The single front wheel 101 is carried by a first fork 102, itself integral with a second fork 103 mounted on the chassis of the stroller, and extending substantially vertically. It is this second fork which is capable of rotation, so that the wheel is directional.

The first fork 102 is connected to the second fork 103 by horizontal axes, on each side, allowing travel of the first fork. Suspension means, formed by a spring 104, controls this travel, so as to improve the comfort of the stroller.

It is noted that the axis 105 of rotation of the wheel is offset rearward, relative to the vertical axis of the second fork 103.

FIG. 11 shows, in section, the connection between the chassis and the second fork 103. It comprises a fixed part 111 formed at the end of the chassis, and a mobile part 112, which can rotate around a vertical axis relative to the fixed part 111. This mobile part comprises means 113 for securing the second fork, and means 114 for receiving the suspension spring 104.

According to the same principle as already mentioned, a movable locking pin in the zone 115 can join the fixed 111 and mobile 112. parts. This aspect is more precisely illustrated in FIG. 12.

In this figure 12, there is shown the pin 121, the end of which is here frustoconical. Its movement is controlled by a cable, circulating in a sheath

122. Again, a spring 123 is provided, tending to bring the pin back into a locked position, in which the pin 121 enters the housing 124 defined in the movable part.

Claims

1. Stroller for children, characterized in that it comprises at least one directional front assembly, comprising a fixed part, integral with the chassis of said stroller, and a part movable in rotation relative to said fixed part, along a first axis of substantially vertical rotation, and carrying at least one wheel, and at least one rigid element mounted on said fixed part, mobile substantially vertically and cooperating with a housing provided for this purpose in said mobile part, forming means for locking / unlocking the rotation of said movable part, designed to secure the latter with said fixed part in a middle position, in which the said wheel or wheels are parallel to the axis of travel of said stroller.

2. Stroller according to claim 1, characterized in that said fixed part is suspended at the end directed towards the front by at least one extension of said chassis, and in that said wheel or wheels are carried by an element integral with said movable part extending along a second substantially horizontal axis, offset towards the rear of said stroller relative to said first axis.

3. Stroller according to any one of claims 1 and 2, characterized in that said fixed part and said movable part are secured to each other by means of an axial fixing means extending according to said first axis of rotation.

4. Stroller according to any one of claims 1 to 3, characterized in that it comprises suspension means mounted between said chassis and said fixed part.

5. Stroller according to claim 4, characterized in that said suspension means comprise at least one spring mounted so that said fixed part, said spring or springs and the end of said chassis carrying said fixed part define a suspension triangle.

6. Stroller according to any one of claims 1 to 5, characterized in that said rigid element has a conical or frustoconical shape.

7. Stroller according to any one of claims 1 to 6, characterized in that said rigid element cooperates with a compression spring tending to bring it into its locked position, when the locked position is selected.

8. Stroller according to any one of claims 1 to 7, characterized in that said locking / unlocking means are controlled remotely, using control means.

9. Stroller according to claim 8, characterized in that said control means comprise a lever or a control button mounted on the handlebars of said stroller.

10. Stroller according to claim 9, characterized in that said control lever is mounted on a control block also comprising a brake control.

11. Stroller according to any one of claims 8 to 10, characterized in that said locking / unlocking means are actuated by cable.

12. Stroller according to claim 11, characterized in that said rigid element is mounted at the end of said cable, and in that said compression spring is mounted on said cable, between said rigid element and a stop.

13. Stroller according to claim 12, characterized in that said control means act on the distance between said stop and the distal end of said rigid element.

14. Stroller according to any one of claims 1 to 13, characterized in that said movable part is movable in rotation relative to said fixed part over a predetermined angular range relative to the axis of travel of said stroller.

15. Stroller according to claim 14, characterized in that said angular range is of the order of 20 to 35 ° on each side of said rolling axis.

16. Stroller according to any one of claims 1 to 15, characterized in that said front axle comprises return means tending to return said movable part to a middle position, in which the said wheel or wheels are parallel to the axis of travel of said stroller.

17. Stroller according to claim 16, characterized in that said return means comprise a torsion spring mounted on said fixed part.

18. Stroller according to any one of claims 1 to 17, characterized in that said front axle comprises means intended to facilitate the movement of said movable part relative to said fixed part.

19. Stroller according to claim 18, characterized in that said means intended to facilitate movement comprise at least one ball.

20. Stroller according to claim 19, characterized in that said means intended to facilitate movement comprise at least three balls, giving a plane support.

21. Stroller according to any one of claims 19 and 20, characterized in that each of said balls is housed in a spherical base drum formed in said fixed part (respectively said movable part) and circulates in a ball path of hemispherical section in said movable part (respectively said fixed part).

22. Stroller according to any one of claims 1 to 21, characterized in that said front assembly forms a suspended front axle.

23. Stroller according to any one of claims 1 to 21, characterized in that it comprises two wheels or wheel blocks extending respectively in the extension of two front stretchers, and each provided with said locking means.

24. Stroller according to any one of claims 1 to 21, characterized in that it comprises a single front wheel or block of wheels, mounted in the extension of a first directional fork.

25. A stroller according to claim 24, characterized in that said wheel or said wheel block is mounted on a second fork, movable in rotation about a horizontal axis relative to said first fork, and in that it has means for suspension between said first and second forks.