Abstract:
A stroller device comprising at least one carriage, the carriage comprising a support unit for supporting at least one person, typically an infant, a wheels assembly coupled to the support unit, an engagement element for engaging the carriage to another such carriage and a pivoting element coupled to the support unit allowing rotating the support unit with respect to the carriage. The support unit may be rotatably reoriented so as to allow transporting the stroller device such that the support unit of the carriage and the other support unit of the other carriage can be aligned in a train state or alternatively in a side-by-side state.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a National Phase Application of PCT International Application No. PCT/IL2008/000577, entitled “Convertible Single and Multi-Seat Stroller”, International Filing Date Apr. 30, 2008, published on Nov. 13, 2008 as International Publication No. WO 2008/135974, which in turn claims priority from Israel Patent Application No. 183033, filed May 7, 2007, both of which are incorporated herein by reference in their entirety. 
     FIELD OF THE INVENTION 
     The present invention relates to strollers and carriages. More specifically the present invention relates to a convertible single and multi-seat stroller 
     BACKGROUND OF THE INVENTION 
     Strollers and carriages (hereinafter referred to as “strollers”) for the transportation of infants and small children have been in use for many years. Also in common use are strollers offering seating options for two children. Typically present day strollers are designed so as to have children seated in different and desired inclination angles and in a fixed-angle position facing frontward, in the direction of the advancement of the stroller. Various assemblies and designs have been developed for reversibly connecting two single strollers to a single double-seat stroller-unit, thus providing a choice of using a two-seater stroller only when necessary and increasing the ease and safeness of maneuverability when transporting two small children, not necessarily of the same age. 
     Given below are prior art patents listing different techniques for the connection of two single strollers to a single stroller unit: 
     In 1928 Chatfield R., in U.S. Pat. No. 1,707,186 invented a device comprising a stretchable wheel axis composed of a shaft with a sliding bar on which, at will, a single or two strollers could be positioned. 
     In U.S. Pat. No. 4,805,938 Redmond T. and Redmond R. invented a device for connecting two baby strollers together consisting of a pair of bars or poll bracket units spaced apart and clamped between frames of the baby strollers so that a single person can operate the strollers simultaneously for transporting two babies therein. 
     In Patent Application WO2005/021351 Thompson J. and Peterson T. describe a device in which two strollers are reversibly connected by aligning and interlocking the front wheels of a stroller with the rear wheels of second stroller, thus more than two strollers can be connected in a column forming “a train” of strollers. 
     In GB 2,368,824 Colin A. describes a device comprising two independent strollers, referred to as “pushchairs”, that can be linked together in either a side-by-side or a column “train arrangement. The linkage is done by “securement members” that interlock the two strollers without any structural adjustments or changes in either of the pushchairs. 
     In GB 2,373,484 Sear L. and Croot C. describe a device comprising rails with a generally rectangular or tubular cross-section that reversibly secure and fasten frames of two strollers in a parallel side-by-side position. In the joint strollers formation one of the two wheels in the front and one of the two wheels in the rear may be inwardly folded by pivots so as to enable the maneuvering of single-stroller unit having just 6 wheels. 
     Typically, the present technology of connecting two strollers to a single stroller-unit, as described in the quoted patents, predetermines the fixation of the two strollers in either a side-by-side positioning or a longitudinal, “train” positioning. 
     In order to be conveniently store and easily transport various mechanical devices have been developed to enable the folding and collapsing of strollers. An example of such a prior art technique for folding is given in U.S. Pat. No. 5,221,106 by Shamie L. in which a stroller comprises two side frames supporting a fabric seat between them; the frames having the ability to fold inwardly by a scissor-motion of a support structure that connects the side frames together. Typically in present day strollers, either collapsible or fixed-frame stroller-units, are composed so that the length dimension of the strollers is predetermined and fixed. 
     The advantage of a stroller in accordance to the present invention is the ability to reversibly connect two independent strollers to a single stroller-unit and when doing so to have the ability to choose a desired state, either a side-by-side or longitudinal, “train” position. In addition to determining the state of two strollers, it is possible in accordance to the device of the present invention, by varying the swirl-angle of the seats to determine the direction-position of two children in connected strollers, either facing each other, facing opposite directions or partially facing each other. 
     Another advantage of a stroller in accordance to the present invention is the ability to change at will the longitude distance between two connected strollers, thus having the possibility of reducing the footprint of the connected strollers by shortening the length dimension of the stroller-unit, facilitating better maneuverability when required. 
     The ability to change at will the distance between two connected strollers has a significant bearing on tempering with the interaction between the children in the strollers, a factor that can be of major importance in transporting children. 
     SUMMARY OF THE INVENTION 
     There is thus provided, in accordance with some preferred embodiments of the present invention, a stroller device comprising at least one carriage, the carriage comprising a support unit for supporting at least one person, typically an infant, a wheels assembly coupled to the support unit, an engagement element for engaging the carriage to another carriage of said at least one carriage, and a pivoting element coupled to the support unit allowing rotating the support unit with respect to the carriage, facilitating the support unit to be rotatably reoriented so as to allow transporting the stroller device such that the support unit of the carriage and the other support unit of the other carriage can be aligned in a train state or alternatively in a side-by-side state. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the device comprises at least two carriages of said at least one carriage. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the engagement element comprises at least one bar and a connector provided with a bore for receiving a matching bar. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the engagement element comprises a hollow bar with an opening into which a matching bar may be inserted and slide. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the device comprises a compacting mechanism so as to facilitate reducing and alternatively increasing the footprint of the stroller device, when the stroller device comprises at least two carriages. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the compacting mechanism comprises a foot actuator. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the wheels assembly comprises at least three wheels. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the wheels assembly comprises four wheels. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the carriage comprises a push-handle. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the push-handle is foldable. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the length of the push-handle is adjustable. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the wheels assembly comprises an elevating mechanism for elevating at least one of the wheels with respect to the other wheels. 
     Furthermore, in accordance with some preferred embodiments of the present invention, at least one of the wheels is detachable from the wheels assembly. 
     Furthermore, in accordance with some preferred embodiments of the present invention, at least some of the wheels of the wheels assembly comprise swivel wheels. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the swivel wheels have a fixed position allowing fixing the swivel wheels in at least one orientation. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the swivel wheels can be fixed in four perpendicular orientations. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the support unit comprises a seat with an adjustable back-rest. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the support unit comprises an adjustable leg-rest. 
     Furthermore, in accordance with some preferred embodiments of the present invention, the carriage is foldable. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to better understand the present invention, and appreciate its practical applications, the following Figures are provided and referenced hereafter. It should be noted that the Figures are given as examples only and in no way limit the scope of the invention. Like components are denoted by like reference numerals. In the Figures the term “frontal side” refers to the side of the single, small wheel, in a single stroller state, as illustrated in  FIG. 1  given below and does not necessarily relate to the direction of motion of the stroller. The “rear side” refers to the side of a single stroller state with the relatively larger wheels and does not necessarily relate to the direction of motion of the stroller. 
         FIG. 1  is an illustration of a single stroller in accordance with a preferred embodiment of the present invention. 
         FIG. 2A  is an illustration of a Wheels Assembly Construction (WAC) of an infant stroller in accordance with the present invention, as viewed from the front. The WAC is shown in a stretched state. 
         FIG. 2B  is a detailed illustration of the frontal section of a WAC, as shown in  FIG. 1 , with a securing-pin in an opened state. 
         FIG. 2C  is a detailed illustration of the frontal section of a WAC, as shown in  FIG. 1 , with a securing-pin in a closed state. 
         FIG. 3A  is an illustration of a WAC viewed from the rear. The WAC is shown in a stretched state. 
         FIG. 3B  is an illustration of a WAC viewed from the rear. The WAC is shown in a compact state. 
         FIG. 4A  is an illustration of two stretched-state WACs placed in a front to front position prior to being connected. 
         FIG. 4B  is a detailed illustration of a section of a frontal wheel axial structure (FWAS) that serves in connecting two WACs, thus connecting two strollers to a single stroller unit. 
         FIG. 5  is an illustration of two stretched-state WACs connected front to front. 
         FIG. 6  is an illustration of two compact-state WACs connected front to front. 
         FIG. 7  is an illustration of two strollers in accordance to the present invention, connected in a stretched longitudinal train-state with the frontal seat swirled perpendicularly to the rear seat. 
         FIG. 8  is an illustration of two strollers in accordance to the present invention, connected in a compact longitudinal train-state. 
         FIG. 9  is an illustration of two strollers in accordance to the present invention; connected in a side-by-side state. 
         FIG. 10A  is an illustration of an apparatus for connecting the push-handle of two strollers in accordance to the present invention in a locked position. 
         FIG. 10B  is an illustration of an apparatus for connecting the push-handles of two strollers in accordance to the present invention in a semi-opened position. 
         FIG. 10C  is an illustration of an apparatus for connecting the push-handles of two strollers in accordance to the present invention in an opened position. 
         FIG. 11A  is an illustration of an assembled swirl-wheel apparatus used in a stroller in accordance to the present invention. 
         FIG. 11B  is an illustration of a disassembled swirl-wheel apparatus used in a stroller in accordance to the present invention. 
         FIG. 12A  is a detailed illustration of the components of the seat apparatus shown in  FIG. 8  and  FIG. 9 . 
         FIG. 12B  is a detailed illustration of an assembled seat apparatus shown in  FIG. 8  and  FIG. 9 . 
         FIG. 13  is a detailed illustration of two not identical strollers positioned to be connected in a longitudinal train-state. 
         FIG. 14  is an illustration of the components of two not identical strollers, positioned to be connected in a longitudinal train-state. 
         FIG. 15A  is an illustration of two not identical strollers connected in a stretched longitudinal train-state. 
         FIG. 15B  is an illustration of two not identical strollers connected in a compact longitudinal train-state. 
         FIG. 16  is an illustration of two not identical strollers connected in a stretched longitudinal train-state with the seats facing each other. 
         FIG. 17A  is a side-view illustration of a single, compactable stroller, as shown in  FIG. 14  in an assembled and ready to be rolled state. 
         FIG. 17B  is a side-view illustration of the stroller in  FIG. 17A  in a folded and minimized state. 
         FIG. 17C  is an illustration of the components of two not identical strollers, connected in a side-by-side configuration. 
         FIG. 18  is an illustration of a single stroller with a wheels axial-structure with a two parallel-bars assembly. 
         FIG. 19  is an illustration of two connected strollers as shown in  FIG. 18 , in a longitudinal train-state. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The present invention is directed at a stroller device that enables the user to reversibly engage or connect (i.e. may be disconnected later) with ease two strollers to obtain a single stroller-unit. The connection can be by either coupling the two strollers in a longitudinal train-state or in a side-by-side state. When connecting, the distance between the connected strollers can be varied at will, from a “compacted” state, referred to as a state where the seats are close to each other, to a “stretched” state, where the seats are wide apart. In the “stretched” state the back of the seats of the frontal seating-position may be reclined substantially more than in the “compacted” state, adding to the comfort of transport. In the compacted state the footprint of the stroller-unit is considerably reduced as compared when in the extended “stretched” state, enabling easier maneuverability in crowded and narrow locations such as when traveling in narrow elevators or strolling along aisles in a shop. 
     When in a longitudinal train-state the direction of the two seats in the stroller-unit can be varied to either having both seats facing the direction of advancing, having the front seat facing the back seat, or having the seats perpendicular to each other. Together with the side-by-side state of the stroller unit, where the seats are positioned in parallel to the direction of advancing, the person guiding the stroller-unit can at will determine the sitting interaction between the two children in the stroller-unit, depending on circumstances and mood of the children. 
     Given below are schematic illustrations of the stroller in accordance with the present invention. It should be clear that the description of the embodiments and attached Figures set forth in this specification serves only for a better understanding of the invention, without limiting its scope. 
     In order to simplify the text describing and explaining the present invention the following abbreviations are used: 
     Seat Support Unit: SSU. The term “seat” refers to include both a proper seat and a cradle or crib for infants. The proper seat can be adjusted and fixed in various sitting states from up right sitting to reclining. 
     Wheels Assembly Construction: WAC. The term “wheels” refers to either a single wheel or a pair wheels assembled in parallel in a single functional unit. 
     Rear Wheel Axial Structure: RWAS, 
     Frontal Wheel Axial Structure: FWAS 
       FIG. 1  is an illustration of a single stroller  10  in accordance with the present invention. The stroller is composed of a SSU  20  and a WAC  12  connected between them by poles or bars designated  28  (of swirling seat support unit  144 , see  FIG. 12A ). The SSU is composed of a push-handle  22  a seat  24  and a sitting support-rail  26 . The WAC is composed of an FWAS  14  and RWAS  34 . Two pairs of relatively large side-wheels  70  and  72  are connected to both sides of the RWAS by a curved bar or pole  46  and  48  (seen in  FIG. 2A ). Each pair of wheels is connected to the end of the connection-bar by a pivot that enables to have the wheels in either a locked, pre-determined position or in freed position, allowing a full free circular movement. The angle of positioning of the wheels  70  and  72  depends on the desired state of connecting two strollers; the implication of which is clarified later in the text. The smaller wheel  74  is either a free swivel wheel or a wheel that can be altered between a free swirl wheel state and a locked, pre-determined position connected by an arm  75  to the FWAS. Further description of the construction of the WAC is given below in the description and explanation of  FIG. 2 . 
       FIG. 2A  is detailed illustration of the WAC  12  viewed from the front. The WAC is composed of two parallel and diagonally running poles  30  and  32  rigidly connected at one end to a RWAS  34  and near the other end, running through, without being permanently fixed in place, to a FWAS  14 . The FWAR has a securing-pin  36  on its vertical sidewall with an opened and closed positions and a release lever  38  for opening the securing-pin. On being closed the securing-pin locks rigidly in place the poles  30  and  32  of the adjacent stroller, running through the FWAR. Two bores run through the FWAS  40  and  42  parallel and diagonally to poles  30  and  32 . The bores, seen more clearly in  FIGS. 2B and 2C , are used for connecting two strollers to obtain a single stroller-unit by joining the WACs of the strollers. The connection mechanism is elaborated in  FIG. 4  and  FIG. 5 , given later in the text. The FWAS and the RWAS are bridged by a segmented bar  50  connected by a hinge  51  to the FWAS and by bearing-rings  44  and  45  ( 45  seen in  FIG. 3A ) positioned around the two wheels-connector bars,  46  and  48 , running perpendicular from both sides of the RWAS. Bar  50  terminates on the RWAS end with a foot-activator  52  that serves as a step-lever for the compaction of the WAC. The compacting mechanism of the WAC is clarified in  FIG. 3A  and  FIG. 3B  given below. The segments of bar  50  are connected by a pivot, designated  58 , seen in  FIGS. 3A and 3B . 
       FIG. 2B  is a detailed illustration of the frontal section of a WAC, as shown in  FIG. 1 , with a securing-pin in the FWAS in an opened state. 
       FIG. 2C  is a detailed illustration of the frontal section of a WAC, as shown in  FIG. 1 , with a securing-pin in the FWAS in a closed state. 
     To further clarify  FIG. 2A ,  FIG. 3A  is an illustration of a WAC  12  viewed from the rear and shown in a stretched state. FWAS  14  and RWAS  34  are bridged by a segmented bar  50  connected by a hinge  51  to the FWAS and by bearing-rings  44  and  45  positioned around two bars,  46  and  48 , running perpendicular from both sides of the RWAS. Bar  50  terminates on the RWAS end with a protruding foot-activator  52  that serves as a step-lever for the compaction of the WAC. 
       FIG. 3B  is an illustration of a WAC viewed from the rear, shown in a compact state. Compaction of the WAC is obtained by pushing the step-lever foot-activator  52  ground-wards. The movement of the step-lever to a vertical position causes the bar bridging the FWAS  14  to the RWAS  34  to fold at a hinge  58 . The bar folding causes overlapping segments of the bar,  60  and  62 , to disengage. With bar  50  folding FWAS is slid on the poles,  30  and  32 , towards the RWAS till both units are in contact. With FWAS slid towards the RWAS the two polls protrude in a “bare” state. The compact state is elaborated in  FIG. 6 . 
       FIG. 4A  is an illustration of two stretched-state WACs  12  placed in a front to front position prior to being to engaged with the poles of each WAC,  30  and  32 , placed so as to fit into the bores  40  and  42  of the adjacent and matching WAC. The securing-pins  36  in the FWAS  14  of both WACs are opened automatically—pushed by the head of the adjacent stroller-inserting pole and close automatically when the secure pin meets the pole hole (by spring or by the elastic of the material-snap). A detailed illustration of the configuring of the poles  30  and  32 , and bores  40  and  42  in a stretched state of a FWAS  14  shown in  FIG. 4A  is given in  FIG. 4B . The securing-pins  36  of each of the FWAS, respectively, is inserted into hole,  19 , in poles  30  of the adjacent stroller. 
       FIG. 5  is an illustration of two stretched-state WACs  12  connected front to front. Poles  30  and  32  of each WAC are inserted into the matching cavities  40  and  42  (seen in  FIGS. 2A and 4B ) in the adjacent WAC and the securing-pins  36  in both WAC in a locked state. 
       FIG. 6  is an illustration of two compact-state WACs engaged front to front. With the FWAS  14  and the RWAS  34  drawn close to each other in both WACs the poles  30  and  32  in each WAC are inserted into the cavities  40  and  42  (seen in  FIGS. 2A and 4B ) of the other WAC in a state that places the four poles in a fixed and tight parallel bundle. 
     Reversing the activities detailed above reverses the connection of compact-state strollers and reverses the compact state of each of the stroller. The bridging bar  50  is stretched by stepping on segment  62 , illustrated in  FIG. 3B , and the RWAS is distanced from FWAS by sliding on the polls  30  and  32 . The polls  30  and  32  of each stroller are withdrawn from the cavities of the adjacent stroller,  40  and  42  after the releasing of the securing pins  36 . In order to separate the strollers the securing pin is released and the strollers are pulled away from each other simultaneously. 
       FIG. 7  is an illustration of two strollers  10  engaged in a stretched longitudinal train-state to form a single stroller-unit  11 . The SSU  20  and the WAC  12  in each stroller are connected by vertical poles or bars  28  connected to the RWAS. Bar  28  connects to the RWAS by a ring around the wheel-axial bar,  46  and  48 , as is further illustrated in  FIG. 3A ,  FIG. 3B  and  FIG. 8 . The connection of the SSU to the RWAS and the structure of the seat support section and its swirling ability are clarified in detail in  FIG. 12A  and  FIG. 12B . The swirling of the seats enable a full circular motion with ability to fix the seats in 90 degree swirling increments, facilitating to seat two infants in either a facing position, a back-to-front position, a side by side position or in a perpendicular 90 degree angle sitting positions, as shown in the Figure. The push-handle  22  in the SSU can be folded by the aid of a pivot  23  on both sides of the handle, thus eliminating obstruction when two strollers are connected. The folding of the push-handle also assists in maneuvering with the stroller in a narrow and/or crowded location. When WAC are connected wheel  74  of each stroller is drawn near the FWAS by pulling the bar-arm connection  75  (see  FIG. 1 ) through a position-fixing tube  77 . The placement of the fixing tube  77  in the FWAS is shown in  2 B, and  4 B When two WAC are connected the side wheels  70  and  72  roll on the ground while the wheel  74  of both WAC are kept in an elevated position, not touching the ground. The side wheels  70  and  72  in the front, in the direction of movement, may be left to swirl freely while the side wheels at the back are fixed in place in the direction of movement. The ability to lock or fix the wheels in 90 degrees increments is elaborated in  FIG. 11B . 
       FIG. 8  is an illustration of two strollers  10  connected in a compact longitudinal train-state to a single stroller unit  11 .  FIG. 8  illustrates the positioning of the two SSU of the strollers in closer vicinity than the positioning in stretched-state, as shown in  FIG. 7 , thus enabling easier maneuverability with the stroller-unit  10 . A leg-rest ( 17   a ,  17   b ) is provided for supporting the legs of the infant sitting on the stroller, bearing in mind the fact that in the process of growing the legs become longer, rendering the leg-rest unnecessary, in which case it is folded away, leaving room for the longer legs (also see  FIG. 15A ). 
       FIG. 9  is an illustration of two strollers  10  connected in a side-by-side state to form a single stroller-unit  11 . The WAC of the two strollers are connected in a compact-state, as illustrated in  FIG. 6  and  FIG. 8 , and wheels  70  and  72  positioned in the breadth-direction of advancement of the stroller-unit  11 . To improve the maneuverability of the stroller  11  in a side-by-side state, depending on circumstances, the frontal direction wheels and/or the back direction wheels of the connected strollers can either be pre-directionally fixed in place of left to be rotationally free to swirl in the advancing direction of movement. See bellow  FIG. 11A  and  FIG. 11B  for illustration and explanation of the wheels apparatus. The push-handles  22  of both strollers are connected by a bridging apparatus  80  illustrated in detail in  FIGS. 10A ,  10 B and  10 C. The mechanism of connecting the push-handles  22  can be of various constructions. The connection, as shown in  FIG. 10A  to  FIG. 10C , is a typical example of such a connection mechanism. 
       FIGS. 10A ,  10 B and  10 C illustrate in a sequence the opening (or closing, if viewed from  10 C to  10 A) of the bridging apparatus  80  connecting the push-handles of two strollers, as shown in  FIG. 9 . 
       FIG. 10A  is an illustration of an apparatus for connecting the push-handle of two strollers in a side-by-side state in accordance to the present invention in a locked position. Apparatus  80  comprises two units,  88  and  89  each positioned on another stroller. Each of the units is hinged by a tube that surrounds push-handle tubes  83  and  85 , respectively, and has an extending plate  84  and  86  (shown in  FIG. 10C ). An elongated knob on a pivot  82 , positioned on plate  86 , is inserted into an elongated narrow cavity  87  in plate  84 . By turning the knob by 90 degrees it can no longer exit the cavity and plates  86  and  84  are interlocked. 
       FIG. 10B  is an illustration of an apparatus for connecting the push-handle of two strollers in a semi-opened position. The knob  82  is turned to be aligned with the narrow cavity  87 . 
       FIG. 10C  is an illustration of an apparatus for connecting the push-handle of two strollers in accordance to the present invention in an opened position. Knob  82  is turned and aligned with the narrow cavity  87 . Plate  84  is swirled upwards around tube  85  and liberates the knob  82 . Plate  86  is swirled downwards and the push-handles of the two strollers are disengaged. 
       FIG. 11A  is an illustration of an assembled swirl-wheel apparatus used in a stroller in accordance to the present invention. The connection of a swirl-wheel apparatus  90  in both of the large wheel pairs in the RWAS is illustrated in  FIG. 1 . 
       FIG. 11B  is an illustration of a disassembled swirl-wheel apparatus  90 , shown in  FIG. 11A . Bar or pole  46  and  48  of the RWAS, as illustrated in  FIGS. 3A and 3B  are each inserted into ring fixture  92  which is mounted on a protruding tube  94  extending from an axial-block  96 . Ring  92  has a hollow hole  106  running through it and a framed slit on its side  109  opened at the bottom. The protruding tube  94  has four equally circumference-spaced vertically framed slits that have the exact width of the slit on tube  92 . A rectangular plate  107  with a handle-ring is inserted trough the slit on ring  92  and into one of the four slits of the protruding tube  94 . The slit of choice in the protruding tube determines the connection-direction of the wheels in 90-degree increments. If the rectangular plate is not inserted into the protruding tube  94  the wheels are free to swirl around pole  46 , with no pre-determined orientation. On insertion of the plate  106  the angle of the wheels in respect to the RWAS is determined. A securing-pin  108  is inserted trough the ring  92  and through hole  113  in bar or pole  46  of the RWAS, thus connecting and fixing the swirl-wheel apparatus  90  to the RWAS. A pair of cogwheels  100  (only one seen in the figure) connects to the axially center of the internal facing side of the pair of wheels  98  and  99 . A stop-paddle is pivotally connected ( 105 ) to the axial-block and has protruding bulges that, on lowering the paddle, insert amongst the cogs of the cogwheels  100  and the stroller comes to a stop. 
       FIG. 12A  is a detailed illustration of some of the components of the Seat Support Unit: SSU designated  20  in  FIG. 1 . The seat-connection apparatus comprises a seat-base unit  174  and a swirling-seat-support unit  144 . The seat-support unit comprises a ring frame  176  positioned horizontally and connected by protruding platform-plates  196  to two vertical support bars  28  that connect to the RWAS. The ring frame  176  has four evenly spaced horizontal holes  192  in the circumference running horizontally through the middle of the wall of the ring. A securing-pin with a handle  182 , having a spring  184  and a screw nut  186  are provided for securing the seat-base unit in place in the seat-support unit. The seat-base unit  174  comprises a ring  188  that fits and “wraps around” the circumference of the seat-base unit  144  and protrudes from a plate  190  in which the ring is embedded. The seat-support ring  188  has horizontal two holes in the circumference running horizontally through the middle of the wall of the ring placed across from each other and both fit to align with the holes of the seat-support frame ring  176 . The locking and securing of the swirl seat-support unit  144  to the seat-base unit  174  is done by inserting the securing-pin  182  through one of the holes, designated  194 , in the “wrapping” ring  188  and through an aligned hole in the “Wrapped”  176 . The decision which of the holes in ring  176  will be aligned with the insertion hole in ring  188  determines the direction positioning of the seat-base unit  174  of the swirl-seat support unit. In connecting the seat-base unit  174  with the seat support unit  144 , spring  184  is compacted and keeps the securing-pin  182  in tension so that when hole  194  is aligned with hole  192  by the swirling of ring  188 , the securing-pin will be automatically inserted into  192  by the power of the spring. Spring  184  is connected to nut  186 , so that when pin  182  is drawn out from the hole spring  184  pulls the pin inwardly, so that when the pin is in front of a hole the pin locks the seat in position. 
       FIG. 12B  is a detailed illustration of an assembled seat-connection apparatus whose components are shown in  FIG. 12A . 
     Another embodiment of the present invention is an easy and comfortable connection of two not identically composed strollers, shown in  FIG. 13  through  FIG. 17B   
       FIG. 13  is an illustration of two disassembled strollers, designated  120  and  122 , having different compositions in a position to be engaged in a longitudinal train-state. For a better understanding  FIG. 13  should be viewed together with  FIG. 14 . Stroller  122  comprises a hollow bar  124 , encompassed on one end by sliding ring-bar  128  and on the other end having two “L”-shaped plates, designated  143  and  145 , that protrude vertically on both sides of bar  124 . The “L”-shaped plates are pivotally connected to connector  227  on bar  124  and wheel axis designated  47 . The sliding ring bar  128  has a reversible snapping mechanism  250  that snaps into bar  124  and locks ring bar into place on bar  124 . On releasing the snapping the sliding bar is free to move. Sliding ring bar  128  has two flanks  132  running diagonally downward in both side-directions. Wheels  134 ,  136 , are connected by connecting-support bar  150 , which can be locked in an engaged lower position or raised to a disengaged position through slots  148  of each flank and (see  FIG. 14  for elaboration). The wheels can be folded and lifted upward, towards bars  124  pulling and changing the state of the support bar  150  in slot  148 . Stroller  120  comprises a hollow bar  126 , encompassed on one end by sliding ring-bar  130  adjacent to a sliding ring bar  152  and having on the other end having two “L”-shaped plates, designated  142  and  140 , that protrude vertically on both sides of bar  126 . The sliding ring bar  152  has a reversible snapping mechanism  252  that snaps into bar  126  and to sliding bar  130 , locking the ring bar into place on bar  126 . On half releasing the snapping the sliding bar is free to move connected sliding bar ring  152 . Full releasing, allows removing the sliding bar  130  with the connected wheels  138 , 139  (the wheels of the other stroller can also be removed similarly). A “U” shaped bar  141  is pivotally connected at  141   a  to the axis points of connector  227  and points  141   b  are connected to connection points  155   a  of “U” shaped bar  155 . Points  155   b  of “U” shaped bar  155  are connected to connecting points  152   a  of sliding ring bar  152  (see  FIG. 14  for further clarification). By stepping down on bar  141  sliding bars  152  and  130  slide along bar  126  towards the “L”-shaped plates and bar  155  rises vertically from bar  126 , so that the two strollers are drawn together to a compact state. In order to return to the stretched position bar  155  is activated, forcing the compacting mechanism back. 
     The “L” plates  140  and  142  of stroller  120  and plates  143  and  145  of stroller  122  are pivotally connected to connector  227  of bar  126  (and similarly to bar  124 ). 
     Curved bar  47  is perpendicularly and fixedly connected to the corners of the “L” shaped plates,  140  and  142 . The bar runs through the “L” plates and has swirl wheel mechanisms  90  connected at both ends. The swirl wheel mechanism  90 , as clarified in  FIG. 11B , can be fixed at different angles. 
     Sliding ring bar  130  has two flanks  132  running diagonally downward in both side-directions. Wheels  138 ,  140 , are connected to the bottom end of the flanks by a slot  148  (better seen in  FIG. 14 ) and the flanks of each two wheels are held rigidly in place by a connecting-support bar  150  engaging the two flanks (see illustrated in  FIG. 14  of elaboration). The wheels can be folded and lifted upward, towards bars  124  pulling and changing the state of the support bar  150 . 
     To connect stroller  120  to stroller  122 , sliding ring bar  128  is connected to sliding bar  130  using reversible locking mechanism (protruding snap pin  256  on bar  128  and catcher  258  on bar  130 ). The reversible snapping mechanism  252  and snap  250  (on sliding ring bar  128 ) are released from bar  124  and  126 . Bar  126  is inserted into bar  124  and simultaneously, bar  124  is inserted into sliding bar  130  and sliding bar  152 . When bar  124  reaches inside sliding bar  152 , the reversible snapping mechanism  252  locks it in position. The wheels  134 ,  136  of stroller  122  and wheels  138 ,  139  of stroller  120  can be disengaged by raising them. 
     The sliding ring bars  128  and  130  of strollers  122  and  120 , respectively, that support the wheels, can be individually of both removed when connecting the two strollers  120  and  122 , leaving four ground rolling wheel-units without additional suspended wheels. The “L” plates ( 140 ,  142  in stroller  120  and  143 ,  145  in stroller  122 ) in both strollers support on the top a swirling seat-connection unit  135 , which supports a seat  146 . The push-handles  220  of the strollers,  120  and  122 , comprise of folded open-ended rectangle bar  222  that can be either stretched or inserted, at will, through connection tubes  226  and into receiving tubes  224 , fixed on both sides of the seat  146 . See  FIG. 14  for the stretched and compacted states of the push-handles. 
     The seat  146  has either an opened, “seatable” state or a folded, compacted state. To understand the transition from one state to the other  FIGS. 13 ,  14 A,  14 B,  17 A and  17 B should be viewed. When in an opened position bar  232  is locked at an angel of about 45 degrees by bar  230 , which is pivotally connected to the seat  146 . Bar  232 , on both sides of the seat, holds the push-handles  220  in an upright “pushable” angle. When folding the seat, a securing pin protruding from opposite sides of the seat, and which resides inside groove  232   a  of bar  232  (bars  232  are symmetrical) is disengaged so that the groove is allowed to slide over it until bars  230  and  232  are aligned in a horizontal position. 
     To fully fold and compact the stroller (stroller  120 ) the “L” shaped plates  140  and  142  are folded. See  FIG. 17A  and  FIG. 17B  for further clarification. 
       FIG. 14  is a detailed illustration of two strollers  120  and  122  positioned to be joined together in a longitudinal train-state.  FIG. 14  should be viewed in conjunction with  FIG. 15A  and  FIG. 15B . Stretched state joining of the two strollers is illustrated in  FIG. 15A , a compact joining of the strollers is given in  FIG. 15B . 
     Disengaging of the two strollers,  120  and  122 , is done by reversing the activities described above for the joining of the strollers. 
       FIG. 16  is an illustration of two strollers  120  and  122  joined in a stretched longitudinal train-state with the seats facing each other. The changing of the angles of the seats  146  is obtained by changing the relative angle of the swirl-seat  146  in respect to the swirling seat-connection unit  135 , seen in  FIG. 13 . 
       FIG. 17A  is a side-view illustration of stroller  120 , shown disassembled in  FIG. 13  and assembled in  FIG. 14 . The stroller is illustrated in stretched state and ready for use. 
       FIG. 17B  is a side-view illustration of one of the stroller  120  shown in  FIG. 13  and in  FIG. 14  in a folded and minimized state. Wheel  90  is raised and reoriented sideways, reducing the overall profile of the folded stroller. The seat and the push handles are horizontally aligned. 
       FIG. 17C  is an illustration of the components of two not identical strollers, connected in a side-by-side configuration 
     Another embodiment of a stroller that can connect to form a multi-seat stroller, in accordance to the present invention, is given in  FIG. 18  and  FIG. 19 . 
       FIG. 18  is an illustration of a single stroller  200  with a two parallel-bars wheels axial-structure  206 . The axial-structure  206  is designed two parallel bars  202  and  204 . The bars enable two independent strollers  200  to be connected and form a single stroller state, as seen in  FIG. 19 . 
       FIG. 19  is an illustration of two connected strollers  200  as seen in  FIG. 18 , forming a single stroller state  210 . The connection of the strollers is done by the attachment of the parallel bars of both strollers. 
     The present invention introduces a novel design for strollers, allowing connecting two strollers in a side-by-side and alternatively in train configuration. At the same time, in some preferred embodiments of the present invention the joined strollers can be compacted offering greater maneuverability and comfort. 
     Conveniently, the two joined strollers can be easily disengaged and used separately. 
     It should be clear that the description of the embodiments and attached Figures set forth in this specification serves only for a better understanding of the invention, without limiting its scope. 
     It should also be clear that a person skilled in the art, after reading the present specification could make adjustments or amendments to the attached Figures and above described embodiments that would still be covered by the present invention.