The object of the invention relates to a transformable device useable for child sport- equipment and baby buggy, which has a frame structure, at least three wheels connected to the frame structure by way of axles, and a child carrier part-unit and seat that may be located on the frame structure, furthermore the axle of at least one of the wheels is connected to a steering column belonging to the frame structure, where the steering column is attached to the frame structure so that it may turn, when the transformable device is in a state suitable for carrying a child at least two adjustably spaced wheels in their outer position separated from each other by an outer distance are connected to the frame structure so that they may rotate by axles at positions different to the wheel connected to the steering column but positioned in the same main plane, furthermore a clamping part-unit is inserted between the child carrier part-unit and the frame structure, with the help of the clamping part-unit the child carrier part-unit is temporarily firmly fixed to the frame structure in such a way that it may be attached and removed, while the transformable device is in its sport device state the same adjustably spaced wheels are arranged at a smaller distance from each other than the outer distance, at an inner distance, and the child carrier part-unit is removed from the frame structure and replaced by the seat.

Over the course of time numerous solutions have been elaborated to facilitate the transportation of children. One of the largest groups of these includes baby buggies of differing sizes, shapes and frames. The multifunction baby buggies used today are not only suitable for facilitating the movement of children not yet able to walk for the person carrying them. AS in recent years those constructions are becoming increasingly widespread that make it possible to transform baby buggies used for the traditional purpose into a sport or free-time device.

Patent specification number KR 2014122158 discloses a solution, for example, in which the frame structure of a two-wheeled children's bicycle can be transformed using various additional components into a tricycle and even into a baby buggy. The disadvantage of the solution, however, is that the transformation demands a certain amount of technical knowledge, takes an extended period of time, and the transportation of the relatively larger sized components is expressly difficult. Therefore, this solution does not make it possible, for example, for the mother of a small child that can already walk but still requires the seat of a baby buggy to simply transform the baby buggy into a run bike, for example.

Utility model specification number CN 204077941 discloses a frame structure in which the wheels and the seat can be more simply moved, and so it is easier to make a baby buggy suitable for carrying a child out of a tricycle. The significant disadvantage of the given solution, however, is that as compared to a tricycle or bicycle arrangement that suitably establishes and develops the child's coordination, there are two wheels on the steerable axle, which does not only make steering difficult, but may also be a source of accidents.

Publication document number US 2011/0062752 relates to a baby buggy from which the child carrier part may be removed and used as a carrycot. This structural arrangement, however, does not make it possible to transform the frame structure into a sport device.

With the structure according to the invention our objective was to overcome the deficiencies of the known multifunction, transformable baby buggies and to create a version that, in addition to having a simple structure, makes it possible to transform a common three-wheeled baby buggy with a small number of motions, without any special skill or the exertion of force being required and without any further parts having to be installed, into a run bike so that suitable and safe steering and manoeuvrability can be retained both in the baby buggy and run bike states, with special respect to the favourable use of the trailing caster wheel.

A further objective was when transforming the baby buggy into a run bike was to be able to be able to remove the child's seat from the frame structure so that it does not constitute something else for the person accompanying the child to hold and take up the use of the person's hand so making moving more difficult and therefore the safe supervision of the child during this time while the child is moving freely by using the run bike. The recognition that led to the solution according to the invention was that if the baby buggy's frame structure is established in an unusual way by connecting the two wheels arranged on a virtual axle, usually at the rear, in a completely novel way to the other part of the frame structure, and, as a result of this, while transforming the frame structure, when these rear wheels approach the longitudinal plane of the frame structure, or become more distant from it, then the position of the longitudinal axis of the steering column attached to the frame structure, and its angle to the ground surface changes to the desired amount, and both in the baby buggy state and the child's run bike state a front wheel position may be established in which depending on the state the baby buggy and the run bike can both be steered safely without any danger of accident, and so the task can be solved.

The idea behind the invention also included that if the structural element serving as the child carrier seat of the baby buggy is provided in a unique way with carrier straps that simultaneously serve as the safety belt of the child seat and as the shoulder straps of a backpack, then the child seat may be carried on a person's back without any difficulty when the transformable device is in run bike state, and so the person supervising the child has both hands free, and with this the given objective may be realised.

In accordance with the set objective transformable device according to the invention that useable for child sport-equipment and baby buggy, - which has a frame structure, at least three wheels connected to the frame structure by way of axles, and a child carrier part-unit and seat that may be located on the frame structure, furthermore the axle of at least one of the wheels is connected to a steering column belonging to the frame structure, where the steering column is attached to the frame structure so that it may turn, when the transformable device is in a state suitable for carrying a child at least two adjustably spaced wheels in their outer position separated from each other by an outer distance are rotatably connected to the frame structure at positions different to the wheel connected to the steering column but have axles symmetrically positioned to the longitudinal main plane of the frame structure, furthermore a clamping part-unit is inserted between the child carrier part-unit and the frame structure, with the help of the clamping part-unit the child carrier part-unit is temporarily firmly fixed to the frame structure in such a way that it may be attached and removed, while the transformable device is in its sport device state the same adjustably spaced wheels are arranged separated from each other by an inner distance smaller than the outer distance, and the child carrier part-unit is removed from the frame structure and replaced by the seat, - set up in such a way that the frame structure has a central part-unit containing a front frame member, rear frame member and a connection piece inserted between the two, where the front frame member and the rear frame member are connected to each other with the help of the connection piece so that they may move as compared to each other, the front frame member of the central part unit is provided with front support protrusions, while the rear frame member of the central part-unit is provided with rear support protrusions, where the front support protrusions are connected to the front frame member so that they may rotate around front axles as compared to the front frame member and the rear support protrusions are connected to the rear frame member so that they may rotate around rear axles as compared to the rear frame member, and the outer end of the front support protrusions opposite to the front frame member and the outer end of the rear support protrusions opposite to the rear frame member are connected together with frame elements supporting the axles of the adjustably spaced wheels also so that they may move, furthermore the main axis of the front axle of the front frame member is at an acute angle of incidence to the base plane drawn through the points of incidence of the axles of the adjustably spaced wheels formed with the adjustably spaced wheels and through the axle of the wheel other than these, and the steering column is rotatably connected to the frame structure via a linking element rotatable around the axle different to the axle of the given wheel, and a position-setting part-unit is interposed between the frame structure, the steering column and the linking element.

A further feature of the transformable device according to the invention may be that the front frame member and the rear frame member are connected to each other so that they may move as compared to each other along the longitudinal main plane of the frame structure with the help of the connection piece. In the case of another version of the invention the main axis of the front axle of the front ^" frame member and the main axis of the rear axle of the rear frame member are at differing angular positions.

In accordance with the set objective another transformable device according to the invention useable for child sport-equipment and baby buggy, - which has a frame structure, at least three wheels connected to the frame structure by way of axles, and a child carrier part-unit and seat that may be located on the frame structure, furthermore the axle of at least one of the wheels is connected to a steering column belonging to the frame structure, where the steering column is attached to the frame structure so that it may turn, when the transformable device is in a state suitable for carrying a child at least two adjustably spaced wheels in their outer position separated from each other by an outer distance are rotatably connected to the frame structure at positions different to the wheel connected to the steering column but have axles symmetrically positioned to the longitudinal main plane of the frame structure, furthermore a clamping part-unit is inserted between the child carrier part-unit and the frame structure, with the help of the clamping part-unit the child carrier part-unit is temporarily firmly fixed to the frame structure in such a way that it may be attached and removed, while the transformable device is in its sport device state the same adjustably spaced wheels are arranged separated from each other by an inner distance smaller than the outer distance, and the child carrier part-unit is removed from the frame structure and replaced by the seat, - set up in such a way that the frame structure is provided with wheel-support axles assembled from axle elements that slide into one another located on the two sides of the longitudinal main plane of the frame structure, and the axles of the adjustably spaced wheels are connected to the outer ends of the wheel- support axles so that they may rotate, the wheel-support axles positioned on the two sides of the longitudinal main plane of the frame structure are arranged symmetrical to the longitudinal main plane, and the angle between the projection of the main axes of the individual wheel-support axles onto the longitudinal main plane and the main axis of the given wheel-support axle is an acute angle, furthermore the steering column is rotatably connected the frame structure with the insertion of a linking element that may be rotated around an axle that is not the axle of the given wheel, and a position-setting part-unit is inserted between the frame structure, the steering column and the linking element.

A further feature of the transformable device according to the invention may be that the axle elements have a cross-section that is not circular, and the area of the cross-section of the axle elements more distant from the frame structure is smaller than the area of the cross-section of the axle elements closer to the frame structure.

In the case of another version of the transformable device the axles of the adjustably spaced wheels when they are at their outer end position and inner end position are set to be coaxial with each other.

In the case of yet another different embodiment of the transformable device the steering column of the frame structure carrying the axle of one of the wheels is assembled from a main piece running through the frame structure and a wheel fork located in its continuation and supporting the axle of the wheel, and the longitudinal axis of the main piece of the steering column and the main axis of the wheel fork are at an acute angle to each other.

In the case of another different embodiment of the invention the linking element has a supporting piece in the vicinity of the upper end opposite to the wheel with a longitudinal axis that is at an angle to the axle of the linking element, while the child carrier part-unit has a resting piece cooperating with the supporting piece, furthermore the frame structure has at least one connection fitting, the child carrier part-unit has at least one linking piece cooperating with the connection fitting, and the clamping part-unit is formed by the combination of the supporting piece, the resting piece cooperating with it, as well as one or more connection fittings and one or more linking pieces cooperating with it. The supporting piece is formed by the structural element used as handlebars when the transformable device is in sport device state.

In the case of a further embodiment of the transformable device one of the connection fittings of the frame structure is formed by the seat located on the frame structure. From the point of view of the invention it may be preferable if when the transformable device is in sport device state the child carrier part-unit is removed from the frame structure and formed into an independent portable pack.

In the case of another different version of the transformable device the child carrier part- unit is provided with carrier straps facilitating its positioning on the user's back. The carrier straps are provided with safety connection elements, and when the child carrier part-unit is being used they are fixed to each other with the safety connection element as a safety belt serving to retain the child. Furthermore, the child carrier part-unit is fitted with a supplementary strap. Optionally the supplementary strap is provided with a connection member that can be fixed with the safety connection element.

The transformable device according to the invention has numerous preferable characteristics. The most important of these is that as a consequence of the unique design of the frame structure and the novel connection of the given wheels, not only can the transformation of the frame structure be realised easily, quickly and without any special effort, but during the transformation the front wheel automatically gets into a preferable position from the point of view of steering and manoeuvrability, which could not be achieved with the known structural arrangements.

Another feature that may be listed among the advantages is that due to the unusual carrier pants of the child carrier part-unit, the child carrier part-unit itself can be simply removed from the frame structure and when the transformable device is in sport device state it does not limit the movement of either the user child nor of the supervising person.

A further significant advantage originating from the above is that the transportation of a tired child in a baby buggy and the development of the child's movement abilities, skill, sense of balance, stamina and musculature can be performed with a single device in such a way that no spare parts or supplementary elements need to be carried by the supervising person in order the change the function of the transformable device, and after transformation there are no independent structural elements that need to be carried, put away or held or that would have a disadvantageous effect on free movement. Another advantage is that as a result of the formation of the frame structure when it is not being used it can be transformed into a small size, and while being used it makes it possible even for a larger child to "travel" in the baby buggy or even go cycling.

Due to the dual function it is a preferable effect of the transformable device according to the invention that it also teaches the child to share the burdens. As when the child sits in the baby buggy, the supervising person performs the "work", while when the transformable device is in run bike state the child getting out of the baby buggy "carries" the device. And this, even when the child is young, helps develop the behaviour that burdens must be shared, and the growing child can participate in this.

Another advantage is that the child carrier part-unit that may be used as a backpack makes it unnecessary for the supervising person to carry another bag, as the objects linked to a walk, such as food, drink, shawl, etc. may be placed in the child carrier part-unit and placed on the supervising person's back when the transformable device is in sport device state, and while the transformable device is in baby buggy state they may be placed on the baby buggy itself.

A feature that may be treated as an economic advantage is that the transformable device may be used for performing several tasks during the long period of the child's growth, and so by purchasing just one single device the child's movement can be organised from infancy up to even school age.

Further details of the transformable device according to the invention will be explained by way of exemplary embodiments with reference to figures, wherein

Figure 1 is a side view of the a possible embodiment of the transformable device according to the invention in baby buggy state,

Figure 2 shows the view of the transformable device according to figure 1 from direction II,

Figure 3 shows the view of the transformable device according to figure 1 from direction III, with the child carrier part-unit removed, Figure 4 shows a view image of the transformable device according to the invention when in sport device state,

Figure 5 shows a side view of another embodiment of the transformable device according to the invention in baby buggy state,

Figure 6 shows the view of the transformable device according to figure 5 from direction VI,

Figure 7 is a schematic view image of the transformable device according to figure 5 with the depiction of certain structural elements,

Figure 8 is a side view of the transformable device according to figure 5 in sport device state,

Figure 9 is the view from the direction IX in figure 8,

Figure 10 is a view image of the child carrier part-unit belonging to the transformable device shown in figure 5 in backpack state.

Figures 1 to 3 show the baby buggy state of the transformable device 1 according to the invention, where the frame structure 10 is provided with the child carrier part-unit 20. It can be observed that a total of three wheels 14, 15, 16 are connected to the frame structure 10. The wheel 14 is located in the longitudinal main plane 10a of the frame structure 10, while wheel 15 and wheel 16 are arranged symmetrically to the longitudinal main plane 10a of the frame structure 10 at a wide distance "Tl" from each other so that the directions of movement of wheel 15 and wheel 16 are parallel to each other.

The wheel 14 is connected to the wheel fork 93 of the steering column 90 so that it may rotate around its own axle 11, while the main piece 91 of the steering column 90 runs through the frame structure 10. The longitudinal axis 92 of the main piece 91 of the steering wheel 90 and the main axis 94 of the wheel fork 93 of the steering column 90 are at an acute angle "γ" to each other. The linking element 40 may be found at the end of the main piece 91 of the steering column 90 falling towards the child carrier part-unit 20, and the supporting piece 60 also used as handlebars is located at the upper end 42 of it.

The axle 41 of the linking element 40 and the longitudinal axis 92 of the main piece 91 of the steering column 90 are preferably coaxial. The longitudinal axis 61 of the supporting piece 60, when the transformable device 1 is in baby buggy state, is preferably at a perpendicular angle "β" to the axle 41 of the linking element 40, and therefore to the longitudinal axis 92 of the main piece 91 of the steering column 90 and, in the case of the given embodiment, to the longitudinal main plane 10a of the frame structure 10 as well.

The linking element 40 that may be made independent of the main piece 91 of the steering column 90 makes it possible in a given situation, when the transformable device 1 is in baby buggy state, for the part of the main piece 91 of the steering column 90 holding the wheel fork 93 to turn around the longitudinal axis 92 of the main piece 91 of the steering column 90 independently of the supporting piece 60, while the linking element 40 and therefore the supporting piece 60 also remain motionless. When the transformable device 1 is in its other state, i.e. when used as a sport device the entire steering column 90 and the linking element 40 constitute a single rigid unit, where the wheel fork 93 and the supporting piece 60 can only turn at the same time.

The position-setting part-unit 50 is interposed between the frame structure 10, the; linking element 40 and the steering column 90, which is responsible for fixing the linking element 40 carrying the supporting piece 60 in a given position to the frame structure 10 so that it cannot move, or in another use state it connects the linking element 40 and the main piece 91 of the steering column 90 to each other, however it permits the connected main piece 91 and linking member 40 to turn together in the frame structure 10 around the longitudinal axis 92 of the steering column 90.

The position-setting part-unit 50 in its one setting is used when the child carrier part- unit 20 is located on the frame structure, and partially rests on the supporting piece 60. In such a case the linking element 40 and the frame structure 10 are fixed to one another so they cannot move.

With the transformable device 1 in this state the resting piece 21 of the child carrier part-unit 20 is connected with the supporting piece 60, which is fixed to the frame structure 10 via the linking element 40 with the help of the position-setting part-unit 50, while the linking piece 22 of the child carrier part-unit 20 is fixed to the connection fitting located on the frame structure 10. In the case of the given embodiment the connection fitting 17 is established in the seat 70 of the transformable device 1.

It must be noted here that the resting piece 21, in the case of the given embodiment, has a geometrical shape that conforms to the shape and size of the supporting piece 60, and creates a positive engagement between the child carrier part-unit 20 and the supporting piece 60. Naturally an independent fixing device, e.g. a button-operated lock link may also be built in between the child carrier part-unit 20 and the supporting piece 60.

Contrary to this the linking piece 22 of the child carrier part-unit 20, in a given case, is locked to the connection fitting 17 formed in the seat 70 via a positive engagement and friction lock device. The connection fitting 17, the linking piece 22 as well as the supporting piece 60 and the resting piece 21 together form the clamping part-unit 30. The linking piece 22-connection fitting 17, and the resting piece 21-supporting piece 60 connections may be any desired connection. The only basic requirement is for the resting piece and the linlcing piece 22 of the child carrier part-unit 20 to create a suitable safe and immovable link between the child carrier part-unit 20 and the frame structure 10 that is easily released.

Figure 2 and figure 3 well illustrate that in the case of the present embodiment of the transformable device 1 the wheel 15 and wheel 16 relatively distant from the longitudinal main plane 10a of the frame structure 10 are each connected to the frame structure by a wheel-support axle 80. The wheel 15 is connected to the given wheel-support axle 80 via the axle 12 and the wheel 16 is connected to the given wheel-support axle 80 via the axle 13. The axle 12 and the axle 13 are independent of each other. It is preferable, however, if the axle 12 and the axle 13 are located on a single straight line when the transformable device 1 is in use.

The wheel-support axles 80 are assembled from axle elements 81 with differing cross- sectional sizes, so that axle elements 81 with a smaller cross-section are located at the outer end 82 of the wheel-support axle 80 closer to the wheel 15 and wheel 16. And the cross- section of the axle elements 81 grows towards the frame structure 10. The axle elements 81 may at least partially slide into each other, and therefore the wheel-support axles 80 are essentially telescopic extending axle.

The wheel-support axle 80 is connected to the frame structure 10 in a unique position. In the case of this embodiment the main axis 83 of the wheel-support axle is inclined downwards and backwards from its end connected to the frame structure 10. Therefore the perpendicular projection 10b of the main axis 83 of the wheel-support axle 80 falling on the longitudinal main plane 10a of the o frame structure 10, and the main axis 83 of the wheel-support axle 80 are at an acute angle 10c to each other.

This arrangement of the wheel-support axle 80 is important because in this way when the wheel 15 and the wheel 16 get from their outer positions to their inner end positions closer to the frame structure 10 by the pushing together of the wheel-support axles 80, not only is a smaller distance "T2" established between the wheel 15 and the wheel 16, as is illustrated in figure 4, but also the rear part of the frame structure 10 closer to the axle 12 and axle 13 gets closer to the ground surface, in other words the end of the frame structure 10 towards the seat 70 drops.

Figure 4 also well illustrates that the wheel 15 and the wheel 16 become so close to the two sides of the frame structure 10 that they essentially work as almost a wheel with a single, wide running surface. When the transformable device 1 is in this state, the child carrier part-unit 20 is taken off the frame structure 10.

In this way the seat 70 performs an actual seating task, while the supporting piece 60 fills the function of handlebars. With the help of the position-setting part-unit 50 the linking element 40 and the steering column are now connected together in the other state, and are able to turn around the longitudinal axis 92 with each other together but independently of the frame structure 10. It is important to emphasise that as a consequence of the retraction of the wheel 15 and the wheel 16 the rear part of the frame structure 10 became closer to the ground surface resulting in the front part of the frame structure 10 tilted around the axle 1 1 of the wheel. And as a consequence of this the longitudinal axis 92 of the steering column 90 is at an acute angle with the plane of the ground surface. In the given state the sport device is easier to steer due to the position of the steering column 90.

Returning to the baby buggy state of the transformable device illustrated in figure 1, it is easy to observe that in this state of use the longitudinal axis 92 of the steering column 90 meets the theoretical plane of the supporting ground surface essentially at right angles. This arrangement makes it possible for the wheel 14 to operate as a trailing caster wheel and turn freely around the longitudinal axis 92 under the frame structure 10. In this way improving the baby buggy's manoeuvrability.

It must also be mentioned here that the position-setting part-unit 50 may also be set up so that it may be used to also fix the main piece 91 of the steering column 90 holding the wheel fork 93 to the frame structure 10 in a given position. This position makes it possible to implement the jogging state when using the transformable device 1 in baby buggy state.

The operation of the transformable device 1 presented in figures 1 to 4 is as follows. Viewing the baby buggy state as the initial state, the wheel 15 and wheel 16 of the transformable device 1 are in the outer position, in other words the wheel-support axles 80 are in pulled-out, fixed state. In this case the longitudinal axis 92 of the main piece 91 holding the wheel fork 93 retaining the wheel 14 is essentially vertical, and the rear part of the frame structure 10 is in upper position. The child carrier part-unit 20 is fixed onto the connection fitting 17 located in the seat 70 of the frame structure 10 and onto the supporting piece 60 fixed on the linking element 40 that is the continuation of the main piece 91.

The position-setting part-unit 50 fixes the linking element 40 to the frame structure 10, but in a given case it makes it possible for the main piece 91 of the steering column 90 to turn around the longitudinal axis 92 as compared to the frame structure 10. In this case the transformable device 1 may be pushed by the user so that the two rear wheels 15, 16 can only rotate their own axles 12, 13, while the wheel 14 positioned under the steering column 90, in addition to rotating around its own axle 11, is also able to rotate around the vertically positioned longitudinal axis 92. This movement, which is customary in the case of three-wheeled baby buggies in use today, makes it possible to easily manoeuver the transformable device 1 in this state on the three wheels.

The transformation of the transformable device 1 takes place in the following way. First the linking piece 22 of the child carrier part-unit 20 has to be separated from the connection fitting 17 on the seat 70 of the frame structure 10, then the resting piece 21 of the child carrier part-unit 20 needs to be separated from the supporting piece 60 of the linking element 40, and then following this the child carrier part-unit 20 may be removed from frame structure 10. Optionally the child carrier part-unit 20, as shown in figure 10, may be folded into a single package "CS", which, after this, the supervising person can carry on his/her back.

After the child carrier part-unit 20 has been removed and the securing of the wheel- support axles has been released the wheel 15 and the wheel 16 connected to the wheel- support axles 80 of the frame structure 10 via the axle 12 and the axle 13 may be pushed towards the frame structure 10. As soon as pressure is exerted from outside onto the wheel 15 and/or the wheel 16, the axle elements 81 of the wheel-support axle 80 slide into one another, and so the long wheel-support axle 80 is telescopically contracted and the wheel 15 and the wheel 16 are at a distance "T2" from each other much shorter than the distance "Tl", as is shown in figure 4. When they reach the inner extreme position the wheel- support axles 80 may be secured once again.

While the wheel 15 and the wheel 16 are being pushed inwards and the wheel-support axles 80 are becoming shorter, due to the particular position of the main axis 83 of the wheel-support axles 80, the rear part of the frame structure 10 drops and becomes closer to the ground surface. Due to this change of position the frame structure 10 tilts, and the longitudinal axis 92 of the steering column 90 rotatably fitted into the frame structure 10 also changes its position with respect to the ground surface, and is no longer perpendicular to it, instead from the direction of the seat 70, it is at an acute angle to it. However, as a result of this the caster wheel function of the wheel 14 is terminated and becomes a simple steerable wheel. Then, by adjusting the position-setting part-unit 50 the securing of the linking element 40 to the frame structure 10 may be released, but simultaneously the linking element 40 and the main piece 91 of the steering column 90 become engaged. As a result of this the wheel 14 that is able to rotate around the axle 11 of the wheel fork 93 of the steering column 90 constitutes a single unit with the supporting piece 60 of the linking element 40, which now performs the function of handlebars. Therefore, with the turning of the supporting piece 60 the wheel 14 is able to rotate around the longitudinal axis 92 of the main piece 91 of the steering column 90.

Following this transformation the baby buggy according to the invention and presented in figure 1 is changed into the sport device illustrated in figure 4, and may be used as a run bike. When the small child gets tired, by performing the operations described above in reverse order the transformable device 1 may once again be transformed into a baby buggy, where the distance between the wheel 15 and the wheel 16 is widened to the distance "Tl", and the rear part of the frame structure 10 rises once again. This restores the angle between the longitudinal axis 92 of the steering column 90 and the ground surface to the perpendicular, and the functioning of the wheel 14 as a caster wheel as well.

Moving over now to figures 5 to 7, they show a different embodiment of the transformable device 1 according to the invention. Although the rear part of the frame structure 10 tilts up and down here also, and the wheel 14 also switches between the functions of caster wheel and steered wheel, the structure of the frame structure 10 is completely different.

This version of the transformable device 1 also has three preferably positioned wheels 14, 15, 16. Where wheel 14 is connected to the wheel fork 93 of the steering column 90 via the axle 11 , while the axle 12 of wheel 15 and the axle 13 of wheel 16 are each connected to a frame element 19c. The rear support protrusions 19b and the front support protrusions 19a connect the frame elements 19c to the central part-unit 18.

The central part-unit 18 contains a front frame member 18a closer to the steering column 90, a rear frame member 18b closer to the frame elements 19c retaining the wheel 15 and the wheel 16, and a connection piece 18c positioned between the two forming a hinged connection with them. The connection piece 18c here is preferably a pneumatic slave cylinder.

The task of the connection piece 18c of the central part-unit 18 here is to make it possible for the front frame member 18a and the rear frame member 18b to become displaced along the longitudinal vertical main plane 10a of the frame structure 10 with respect to each other, which movement is an essential condition for the transformable device 1 according to the embodiment to appropriately change function.

Figure 6 illustrates well that the front support protrusion 19a is connected to the front frame member 18a along the front axle 18d, while the outer end 19aa of the front support protrusion 19a more distant from the front frame member 18a is connected to the frame element 19c carrying the axle 12 of the wheel 15. The front support protrusion 19a is connected to the front frame member 18a so that it may tilt around the main axis 18e of the front axle 18d and the outer end 19aa of the front support protrusion 19a is also connected to the frame element 19c so it may tilt. The same may be said about the connection of the frame element 19c retaining the axle 13 of the wheel 16, the other front support protrusion 19a, and the front frame member 18a as well.

In addition to the front support protrusion 19a each frame element 19c is also connected to the outer end 19ba of the rear support protrusion 19b. While the rear support protrusion 19b is connected to the rear frame member 18b of the central part-unit 18 through the rear axle 18f so that it may tilt around the main axis 18g of the rear axle 18f.

As the frame structure 10 is symmetrical along the longitudinal main plane 10a, the individual front support members 19a and rear support members 19b are arranged symmetrically along the longitudinal main plane 10a.

With the central part-unit 18, the front support protrusions 19a and the rear support protrusions 19b in the given position the wheel 15 and the wheel 16 are separated from each other by the wider distance "Tl", which in this way make transporting the child placed in the child carrier part-unit 20 safe. Another important characteristic of the given embodiment that ensures appropriate operation can be seen in figure 7. Here the schematic arrangement of the wheel 14 rotating around the axle 1 1 , the wheel 15 rotating around axle 12 and the wheel 16 rotating around the axle 13, as well as of the front frame member 18a and the rear frame member 18b is illustrated. It is a basic requirement for the base plane "AS" passing through the point of intersection 12a of the wheel 15 and the axle 12, the point of intersection 13a of the wheel 16 and the axle 13, and the axle 11 and the main axis 18e of the front axle 18d of the front frame member 18a to be at an acute angle of incidence "a" to each other. Another requirement is that the main axis 18e of the front axle of the front frame member 18a and the main axis 18g of the rear axle 18f of the rear frame member 18b should not be parallel. This condition and the ability to displace the front frame member 18a and the rear frame member 18b in the longitudinal main plane 10a makes it possible for the frame structure to be transformed in the desired way.

Returning now to figure 5 the connection between the child carrier part-unit 20 and the frame structure 10 can be easily seen. The clamping part-unit 30 can also be found here, which contains the resting piece 21 and the linking pieces 22 belonging to the child carrier part-unit 20, as well as the supporting piece 60 and the connection fittings 17 forming a part of the frame structure 10. The supporting piece 60 and the resting piece 21 are essentially identical to that disclosed in the case of the other embodiment. However here the connection fitting 17 is not located on the seat 70 of the frame structure 10, instead it is a positive engagement device formed on the frame element 19c. The support arm-like linking pieces 22 protruding from the child carrier part-unit 20 are connected to these connection fittings 17.

It must also be mentioned that the connection between the frame structure 10 and the steering column 90 is the same as that disclosed in the case of the previous embodiment. The wheel fork 93, which is fixed to the main piece 91, forming a part of the steering column 90 and retaining the axle 1 1 of the wheel 14 is also to be found here. The longitudinal axis 92 of the main piece 91 and the main axis 94 of the wheel fork 93 are also at the acute angle "γ" to each other. Furthermore the linking element 40 that is located as a continuation of the main piece 91 of the steering column 90 is also to be found here and the supporting piece 60 is located at the upper end 42 of the linking element 40. Here too the longitudinal axis 61 of the supporting piece 60 is at right angles to the axle 41 of the linking element 40. In the case of this embodiment also the position-setting part-unit 50 may be found between the linking element 40, the steering column 90 and the frame structure 10, the purpose of which is that same as that in the other embodiment.

Figures 8 and 9 illustrate the collapsed, i.e. the sport device form of the transformable device 1 according to the given embodiment. Figure 9 well illustrates that the distance "T2" between the wheel 15 and the wheel 16 is much smaller that the distance "Tl" ^' indicated in figure 6. Figure 8 depicts that the child carrier 20 part-unit has been removed from the frame structure 10 and that only the seat 70 protrudes from the frame structure 10. The front frame member 18a and rear frame member 18b of the central part-unit 18 are slipped next to one another covering the connection piece 18c that holds them together, and the front support protrusion 19a and the rear support protrusion 19b are positioned under one another and smoothed up next to the front frame member 18a and the rear frame member 18b of the central part-unit 18. And the longitudinal axis 92 of the steering column 90, contrary to that depicted in figure 5, does not intersect the ground surface supporting the transformable device 1 at right angles, but at an acute angle when viewed from the direction of the seat 70.

The structure of the child carrier part-unit 20 should also be mentioned here, which, as is usual in the case of baby buggies and illustrated in figure 5, contains carrier straps 23 serving to secure the child in the seat and guided over the child's shoulders, the safety connection elements 24 located on them and cooperating with each other, and the supplementary strap 25 that may be guided between the child's legs, as _, well as the connection member 26 belonging to it but locking in unison with the safety connection elements 24.

When the transformable device 1 disclosed in figures 5 to 9 is in use the frame structure 10 in baby buggy state is in open state. The front support protrusions 19a and the rear support protrusions 19b symmetrically arranged on the two sides of the central part-unit 18 of the frame structure 10 are in open state in a form protruding outwards and backwards from the front frame member 18a and the rear frame member 18b of the central part-unit 18, and so the wheel 15 and the wheel 16 are separated from each other by the distance "Tl". And the child carrier part-unit 20 is located on the frame structure 10.

When transforming the transformable device 1 from baby buggy into sport device after removing the child carrier part-unit 20 and, as shown in figure 10, changing it into a pack "CS", and as the wheel 15 and the wheel 16 approach each other, the outer ends 19aa of the front support protrusions 19a and the outer ends 19ba of the rear support protrusions 19b approach one another. During this the front support protrusions 19a rotate around the main axes 18e of the front axles 18d of the front frame member 18a, and also rotate as compared to the frame elements 19c. While the rear support protrusions 19b rotate around the main axes 18g of the rear axles 18f of the rear frame members 18b, and also rotate as compared to the frame elements 19c.

However, the main axis 18e of the front axle 18d of the front frame member 18a is not parallel with the main axis 18g of the rear axle 18f of the rear frame member 18b. The outer end 19aa of the front support protrusion 19a and the outer end 19ba of the rear support protrusion 19b are located on a single frame element 19c. Therefore the front support protrusion 19a and the rear support protrusion 19b are only able to approach one another, with causing permanent damage or breakage, if the front frame member 18a and the rear frame member 18b change their positions as compared to each other. As the front frame member 18 a and the rear frame member 18b can be slid as compared to each other in the longitudinal main plain 10a of the frame structure 10, only the sliding path is determined by the connection piece 18c that links the front frame member 18a and the rear frame member 18b.

In this way then the front frame member 18a and the rear frame member 18b of the central part-unit 18 go from the pulled apart state illustrated in figure 5 to the closed up state illustrated in figure 8, and in the meantime the front support protrusion 19a and the rear support protrusion 19b turn towards the central part-unit 18 and move to be flush up against it. The wheel 15 and the wheel 16 arrive up to the two sides of the frame structure 10, as shown in figure 9, during which the distance between the wheel 15 and the wheel 16 drops to the distance "T2".

While the front frame member 18a and the rear frame member 18b of the central part- unit 18 are approaching one another the inclination of the frame structure 10 with respect to the ground surface also changes, as a consequence of which the previously vertical longitudinal axis 92 of the main piece 91 of the steering column 90 also tilts and, as is well illustrated in figure 8, by the end of the transformation of the frame structure 10, is at an acute angle to the ground surface. Therefore the wheel 14 operating as a caster wheel in baby buggy state is "transformed" into an easily steerable wheel.

In summary then even in the case of the frame structure 10 arrangement different to the other and used in the case of this embodiment the same change of state takes place during the transformation between the two use states. In other words the position of the steering column 90 retaining the front wheel 14 and the resulting functional movement change in addition to the rear wheel 15 and rear wheel 16 approach each other or are separated from each other.

Moving now to figure 10, it illustrates the child carrier part-unit 20 according to figure 5 in folded up state transformed into a pack "CS". Here the carrier strap 23 of the child carrier part-unit 20 provided with connection elements 24 serving to secure the child in the child seat serve for putting on the pack "CS" as a backpack, while the other fittings are located on the inside of the folded up child carrier part-unit 20, i.e. they are covered up.

In this way then the child carrier part-unit 20 when removed from the frame structure 10 may be easily worn on the responsible person's back, and may serve as a backpack as long as the child is using the transformable device 1 as a sport device.

As a single necessary auxiliary device the transformable device according to the invention may be used to good effect for transporting smaller children and also for satisfying their demand for movement, while the child's movement skills, sense of balance and musculature may be suitably developed, but the child's physical burdening is not exaggerated, as when the child becomes tired, the child may sit back in the sport device that may also be used as a baby buggy.

List of references

transformable device frame structure 10a longitudinal main plane

10b perpendicular projection 10c angle

11 axle

12 axle

12a point of intersection

13 axle

13a point of intersection

14 wheel

15 wheel (adjustably spaced)

16 wheel (adjustably spaced)

17 connection fitting

18 central part-unit

18a front frame member 18b rear frame member 18c connection piece

18d front axle

18e main axis

18f rear axle

18g main axis

19a front support protrusion

19aa outer end

19b rear support protrusion

19ba outer end

19c frame element 0 child carrier part-unit 21 resting piece

22 linking piece

23 carrier strap

24 safety connection element

25 supplementary strap

26 connection member 0 clamping part-unit 0 linking element 41 axle

42 upper end 0 position-setting part-unit 0 supporting piece 61 longitudinal axis 0 seat 0 wheel-support axle 81 axle member

82 outer end

83 main axis 90 steering column 91 main piece

92 longitudinal axis

93 wheel fork

94 main axis

"AS" base plane

"CS" pack

"Tl" distance

"T2" distance

"a" angle of incidence

"β" angle

"γ" angle