Folding baby stroller

Technical field of the invention [0001] The present invention relates to baby prams, and more particularly to off-road baby prams that can be folded.

Description of the Prior Art of the Invention [0002] Traditionally, baby pushchairs have been used to push an infant slowly on a relatively hard, smooth floor or pavement. As a result, pushchairs were made small and light. These pushchairs work well enough at low speeds, but are extremely bulky and even dangerous on uneven surfaces or at higher speeds.

[0003] All-terrain baby prams have been designed to overcome these problems. These pushchairs usually use much larger wheels, often large bicycle tires.

[0004] The stroller frame components are constructed of metal tubes and frame connectors of durable plastic or other durable material to connect the frame components together to handle the harsh operating conditions they may encounter. The frame connectors are also used to rotate or swivel one frame element relative to the other, and are used to detachably connect other frame elements together.

[0005] Some advanced designs of off-road pushchairs have allowed some degree of folding of off-road baby pushchairs, with less than desirable compactness. In addition, conventional folding mechanisms include complications that increase cost and reduce reliability and ease of use.

[0006] Document EP 0894693 A2 discloses a foldable baby stroller having laterally spaced front wheel brackets on the left and right, with the front wheel mounted to their front end, and a laterally extending rear axle with the rear wheel mounted to its each end. The trolley further includes laterally spaced rear wheel brackets on the left and on the right, each with a lower end attached to the rear axle and an upper end portion with an upper end; and laterally spaced handle brackets, left and right, each having a front and rear end with a handle extending between them. The stroller also includes laterally spaced folding assemblies on the left and right, each with a pair of mounting plates and a guide articulated between them and rotatable with respect to them. The rear end of the respective bracket among the front wheel brackets is permanently attached between the plates. The front end of the respective one of the handle brackets is articulated between the plates and pivotally relative to the front wheel bracket as a set, in the first and second sequential rotational movement from the extended position to the folded position. The upper end portion of the respective one of the rear wheel brackets is located between the plates with the upper end pivotally attached to the front end of the respective handle bracket for applying motive force to it through the handle bracket. The guide has a hole in the upper end part of the corresponding rear wheel bracket placed in it slidingly. The guide and guide hole are adapted to rotate the respective rear wheel bracket along with the rotation of the respective handle bracket in response to the driving force applied to the respective rear wheel bracket during both the first and second rotational movement of the respective handle bracket, and to move the upper end portion the corresponding rear wheel bracket in the guide hole, with the rotation of the respective handle bracket in response to the motive force applied to it during the second rotation of the respective handle bracket. The rotation and sliding movement of the respective rear wheel bracket moves the respective rear wheel bracket from the extended position to the folded position. Figure 6 shows an embodiment of the invention in which the folding mechanism comprises a sun gear, planetary gear and gear ring, each gear being attached to one of the three frame members and the gears rotating together to fold the stroller frame.

[0007] Document DE 19631776 discloses articulation to articulated parts of a cart, lawn mower or similar small vehicle, the articulation comprising at least two housing parts that are movable relative to each other and each having an articulated shaft. The housing parts contain a planetary gear and contain a shaft that is connected to the planetary gear, protrudes from at least one part of the housing and can be permanently attached.

BRIEF SUMMARY OF THE INVENTION [0008] The present invention relates to a foldable baby pram and folding mechanism used in a foldable baby pram.

[0009] The folding mechanism according to claim 1, comprises a frame of a foldable baby pram, for use with at least one front wheel and rear wheels, comprising: the laterally spaced front wheel brackets on the left and right, with each of the front wheel brackets on the left and on the right having an end portion, the front wheel brackets being adapted to attach at least one front wheel to them, and the front wheel brackets, on the left and on the right, rotate as one unit; the rear-mounted rear wheel brackets on the left and on the right, with each of the rear wheel brackets on the left and on the right having an end portion, each of the rear wheel brackets being adapted to attach at least one rear wheel to them and the rear wheel brackets, on the left and on the right, rotate as one unit; laterally spaced handle elements on the left and on the right, where each of the handle elements, on the left and on the right, has an end part, with each of the handle elements having a part of the handle, and the handle elements on the left and on the right, rotate as one unit; and laterally spaced folding assemblies, left and right, each of the folding assemblies, left and right, each having a first rotating element and a second rotating element rotatably connected to a rotating element, the first rotating element having the first hole with the first rack and the second rotary element has a second hole with the second rack, each of the folding units on the left and on the right, further includes a third rack located in both the first and second bore fastened to the first rack and the second rack so that the first rotary element and the second rotary element rotate relative to each other in directed coordination, and the rotary element is supported by the end portion of one of the supports the front wheel, rear wheel brackets and handle parts on the appropriate side, to rotate the first and second elements about a common axis of rotation, the end part of another element among the front wheel bracket, the rear wheel bracket and the handle element on the respective side is attached to the first rotating element and the end part of yet another element among the front wheel bracket, the rear wheel bracket and the handle element on the corresponding side is attached to the second rotary element.

Preferably, the first rack is formed in the first edge portion of the first rotary member forming the first opening, and the second rack is formed in the second edge portion of the second rotary member forming the second opening, each of the left and right folding assembly.

[0011] Preferably the first and second edge portions are radially offset from each other.

[0012] Conveniently, the first opening is elongated and the second opening is elongated, wherein the elongated first and second holes overlap at least partially.

Preferably, the first rack has a first pitch diameter and the second rack has a second pitch diameter, wherein the first pitch diameter and the second pitch diameter are not the same.

[0014] Preferably, the first pitch diameter of the first rack is sized to rotate one of the front wheel bracket, rear wheel bracket and handle member, attached to the first rotary element by a first rotation angle, from the folded position to the folded frame position of the baby pram. spacer, and in which the second pitch diameter of the second rack is sized to rotate one element from the front wheel bracket, the rear wheel bracket and the handle element, attached to the second rotary element by a second rotation angle, from the folded position to the folded frame position, of the baby stroller, the first and second rotation angles are not the same.

[0015] Conveniently, the first rack has a first helical pitch and the second rack has a second helical pitch, different from the first helical pitch, and wherein the third rack includes a first rack portion with a first helical pitch and a second rack portion with a second pitch helical, with the first and second parts of the third rack rotating as one unit, and the first portion of the rack of the third rack is mounted in the first hole fastened to the first rack and the second portion of the rack of the third rack is mounted in the second hole fastened to the second rack.

[0016] Preferably the rotatable element is supported by the upper end portion of the respective one of the rear wheel brackets on the left and right to rotate about a common axis of rotation.

[0017] Preferably, the front wheel brackets rotate by a first angle of rotation from the folded position to the folded frame position of the baby pram, and the handle elements rotate by a second angle of rotation from the folded position to the folded frame position of the baby pram, the first and the second rotation angle are not the same.

[0018] Conveniently, the first rack has a first helical pitch and the second rack has a second helical pitch, the same as the first helical pitch, and wherein the third rack includes a first rack portion with a first helical pitch and a second rack portion with a second pitch helix, the first and second parts of the third rack rotating as one unit, and the first portion of the rack of the third rack is mounted in the first elongated hole momentarily connected to the first rack and the second portion of the rack of the third rack is seated in the second elongated hole fastened to the second rack.

[0019] Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF PARTICULAR VIEWS OF THE DRAWINGS [0020]

Figure 1 is an isometric view of an implementation of a baby pram, an embodiment of the present invention, an exemplary embodiment shown in a completely unfolded state, ready for use

Figure 2 is an isometric view of the frame of the stroller of Figure 1 without the seat and leg cover.

Figure 3 is a front view of the frame of the pushchair of Figure 2.

Figure 4 is a side view of the frame of the pushchair of Figure 2.

Figure 5 is a side view of the frame of the pushchair of Figure 2, shown in a partially folded state.

Figure 6 is a side view of the stroller frame of Figure 2, shown fully assembled, with both the left and right front brackets and the left and right handle brackets rotated around their respective side folding assemblies towards the respective rear side brackets wheels and with the front wheel removed.

Figure 7 is an exploded isometric view of the folding assembly on the right of the embodiment shown in Figure 1, the folding assembly on the left is a mirror image thereof.

Figure 8 is an enlarged, partial view from the right of the folding assembly on the right of Figure 7, with its outer casing half removed and in a completely unfolded state.

Figure 9 is a partial view from the left of the folding assembly on the right of Figure 7, with its inner housing half removed and in a partially unfolded condition.

Figure 10 is an enlarged isometric view of the pinion and mandrel used in the alternative embodiment of the syntax assembly shown in Fig. 12, where the pinion has two toothed portions.

Figure 11 is an enlarged isometric view of the pinion and mandrel used in yet another alternative embodiment of the syntax assembly shown in Fig. 13, wherein the pinion consists of two gears attached together for use.

Figure 12 is an exploded isometric view, corresponding to Figure 7, of the folding assembly on the right of an alternative embodiment of the folding assembly, the folding assembly on the left being a mirror image thereof.

Figure 13 is an exploded isometric view corresponding to Figure 7 of the folding assembly on the right of yet another alternative embodiment of the folding assembly, the folding assembly on the left being a mirror image thereof.

Figure 14 is an exploded isometric view, corresponding to Figure 7, of the central folding assembly used in the double baby stroller shown in Fig. 15 having two release levers.

Figure 15 is an isometric view of an exemplary embodiment of a double baby stroller, an embodiment of the present invention, shown in a fully unfolded state, ready for use, but without a seat and leg cover.

DETAILED DESCRIPTION OF THE INVENTION [0021] As shown in the drawings for illustrative purposes, the present invention is implemented in the form of an off-road baby pram 10, shown in Figure 1, having a foldable tubular metal frame 12 and a transversely extending rear axle assembly 14 with transverse , non-rotating tubular rear axle 15. The rear wheels 16, on the left and right, are rotatably mounted at the ends of the rear axle assembly 14. The front end of the frame 12 has a single front wheel 18 rotatably mounted thereto.

[0022] The frame 12 has no frame base members extending backwards from the front wheel 18 to the rear axle assembly 14, as is the case with most conventional off-road pushchairs. Instead, the frame 12 comprises, on the left and right, inclined downwards and forwards, elements or brackets 20 of the front wheels, each of which extends downwards from the respective one of the folding assemblies 22 on the left and right, in a configuration tapered to the front wheel 18. The front free end 20a of each of the front wheel brackets 20, on the left and right, has a plastic front wheel connector 20b permanently attached thereto, and the corresponding one of the left and right ends of the front wheel axle 18a 18 is detachably attached thereto, to mount the front wheel to the pram frame 12.

[0023] The brackets 20 of the front wheel are connected to each other by means of a footrest 23, which extends between them, in the direction but back of their front free ends 20a, and which is permanently attached to each bracket in a rear position axis 18a of the front wheel, and extends partly above the front wheel 18. As a result of the interconnection provided by the footrest 23, and also by the front wheel 18, when attached to the front wheel connectors on the left and right, the front wheel brackets 20 on the left and right form a stationary unit relative to the folding assemblies 22, on the left and right when folding and unfolding the pushchair 10, as will be described in more detail below.

[0024] The frame 12 also includes upward and backward sloping elements or brackets 24 of the handle frame, left and right, each of which extends upward from the respective one of the folding assemblies 22, left and right, in configuration generally parallel to handle 26, extending between the handle brackets on the left and right. The handle is covered with a foam handle. The handle brackets 24 are connected to each other by means of a handle 26, which extends between them at their extreme rear and extreme upper end and is permanently attached to each of them.

[0025] As a result of the interconnection provided by the handle 26, the left and right handle brackets 24 move as one assembly with respect to the folding assemblies 22 on the left and right when folding and unfolding the pushchair 10 as will be described in more detail below. It should be noted that in place of the connecting handle 26, each handle bracket 24 may include a portion of the handle at its upper end, such as that used in umbrella strollers.

[0026] In the embodiment of the invention shown in the drawing, the left and right handle brackets 24 and the handle 26 are formed as an integral unit by bending a single piece of aluminum tube. The handle brackets 24 on the left and right are movable relative to the front wheel brackets 20 on the left and right to fold the pushchair 10 and do not form an integrated rigid upper frame together.

[0027] The frame 12 also includes, on the left and right, inclined downwards and backwards, elements or supports 30 of the rear wheel frame, each of which extends downwards from the respective one of the folding assemblies 22, left and right , in a configuration generally parallel to the rear axle assembly 14. The rear free end 30a of each of the rear wheel brackets 30 on the left and right side is permanently attached to the tubular rear axle 15 towards the respective one of the left or right ends of the tubular rear axle 15. The rear wheel brackets 30 are interconnected by rear axle assembly 14, which extends between them at their rear free ends 30a. The U-shaped cross member 31 extends between the rear wheel supports 30 on the left and right. As a result of the interconnection provided by the rear axle assembly 14 and the transverse frame member 31, the rear wheel brackets 30, on the left and right, move as one assembly with respect to the folding assemblies 22, on the left and right, for folding and unfolding the pushchair 10 as will be described in more detail below. The rear wheel brackets 30 on the left and right are also movable relative to the front wheel brackets 20 on the left and right, and the handle 24 brackets on the left and right to fold the pushchair 10. In addition, the rear wheel brackets 30, on the left and right and the rear axle assembly 14 connected to them do not form part of the base frame extending between the rear and front wheels 16 and 18. A large part of the structural strength of the pushchair 10 and the interconnection of the front wheel brackets 20, the handle brackets 24 and the rear wheel brackets 30 is provided by centrally located folding assemblies 22 on the left and right instead of the base frame.

[0028] In the embodiment example of the pushchair 10, the front wheel brackets 20 on the left and right side, the handle 24 brackets on the left and right side, and the rear wheel brackets 30 on the left and right side are made of a tube aluminum. Appropriate alternative materials may be used.

[0029] The left and right outer ends of the tubular rear axle 15 are open and threaded internally to receive a threaded steering knuckle axle 32 forming part of the respective one of the left and right rear wheels 16. A lock nut (not shown) after tightening to the axle face switch 32, blocks the switch axle against loosening when using the pushchair 10. Alternative constructions for permanently or releasably mounting the rear wheels 16 to the tubular rear axle 15 can be used, and any suitable alternative way of attaching the rear wheels 16 to the rear wheel supports 30 can be used.

[0030] The frame 12 of the pushchair 10 is shown in Figure 1, fully unfolded, with fabric seat 33a, and with leg support and fabric cover 33b. The seat 33a is suspended from the handle brackets 24 on the left and right, and the leg cover 33b extends between and is supported by the front wheel brackets 20 on the left and right. For illustrative purposes, the frame 12 is shown in Figure 2 without the seat 33a and leg covers 33b.

[0031] For the depicted implementation, user action will now be described regarding folding assemblies 22 on the left and right. The folding assemblies 22 on the left and right have the same design, one being a mirror image of the other, and the following description although in the singular applies to both assemblies. Each of the rear wheel brackets 30 on the left and right supports a lever 34, extending inwards, which has a mainly vertical orientation, as shown in Figure 3, when the frame 12 of the pushchair 10 is locked in the fully unfolded position. To begin the process of folding the frame 12, each of the levers 34 is pulled up and inward, as shown by arrows R1, to bring the folding assemblies 22 on the left and right to the unlocked state, as will be further explained below. The strap (not shown) can be connected with its ends to the levers 34 to facilitate the movement of both levers at the same time.

[0032] When each of the folding assemblies 22 on the left and right side is in the unlocked state, the handle brackets 24 on the left and right side, together with the handle 26 and the front wheel bracket 20 on the left and right side, together with with the front wheel 18, they can be rotated around the left and right folding assembly respectively, towards the rear wheel supports 30, left and right, respectively, as shown by the arrows R2 shown in Figure 4. As shown in the drawing, when the pushchair 10 is folded, the folding assemblies 22 allow a larger angle of rotation of the handle brackets 24 (greater than 90 °) than for the front wheel brackets 20 (less than 90 °). As explained further below, the front wheel brackets 20 move in targeted coordination with the movement of the handle brackets 24. When the frame 12 is folded, the brackets 20 of the front wheel 20 are rotated clockwise around the folding assemblies 22, as seen in Figure 4, while the handle brackets 24 are also rotated counterclockwise, around the folding assemblies, as seen in Figure 4. The frame 12 is shown partially assembled in Figure 5. In the fully assembled state, both the front wheel brackets 20 and the handle brackets 24 were rotated in targeted coordination with each other around the folding assemblies 22 to be positioned near the rear wheel brackets 30 as shown in Fig. 6. To do this, the front wheel 18 is removed.

[0033] The folding assembly 22, on the right, is shown in an exploded view in Figure 7 and comprises a transversely located front rotary member 35 'and a transversely located rear rotary member 35' 'each having a flat surface face facing the second element. The front rotary element 35 'has a plate or disk 36' with a central part of the plate having a central hole 37 '. The front rotary member 35 'also includes a notch 38', radially outward facing, an inner rack 39 ', in the elongated hole 41', and an arm 40 '. The rear rotary element 35 "has a plate or disk 36" with a central part of the plate having a central hole 37 ". The rear rotary element 35 "also contains a 38" notch, radially inward, the inner rack 39 "" in the elongated hole 41 "" and the arm 40 "". For each of the 35 'and 35' 'rotary elements, the 36' and 36 '' discs and the 40 'and 40' 'arms are shown as formed as part of a single flat plate;

however, in other embodiments, the discs and arms are individual parts that are permanently attached to each other.

[0034] The rotatable elements 35 'and 35' ', together with the corresponding one of the rear wheel brackets 30, are arranged between the inner and outer slotted halves of the housing 42, which allows the arms 40' and 40 '' to project outside the housing. The inner wall of each housing half 42 has a recess 42a of a size and shape that, when the two housing halves are located together, the recesses form a cavity into which the upper free end portion 30b of the respective rear wheel bracket 30 penetrates, and the upper free end portion 31 cross frame. A bolt (not shown) extends through the hole 42f in each half of the housing 42 and through the hole 30c in the top portion 30b of the free end of the rear wheel bracket 30 and the hole in the top of the free end of the frame transverse member 31 to securely clamp the rear wheel bracket and member transverse frame between the inner and outer half of the housing.

[0035] The central holes 37 'and 37' 'of the targets 36' and 36 '', respectively, are sized to receive a sleeve 43 passing through them having a length greater than the combined thickness of the two targets. The 35 'and 35' 'rotating elements are pivotally mounted on the sleeve to rotate within the housing 42 in parallel rotation planes about the axis of rotation transverse to the plane of the 36' and 36 '' discs. The end portions of the sleeve extend beyond the central holes 37 'and 37' ', each having a circumferential groove 43a in which the clamp 43b, in the shape of a letter, engages, to hold the sleeve 43 in place. The sleeve 43 also passes through the washer 43d located between the discs

36 'and 36 ° of 35' and 35 '' rotational elements to serve as a spacer and bearing surface for the rotational movement of rotary elements around the bushing 43. Each of the 36 'and 36' 'discs has a flat face in combination with the flat face of the other shield, with a 43d washer between them.

[0036] Each of the end portions of the sleeve 43 extending beyond the C-shaped clamp 43b is located in and held by a retaining cup 42b formed by an inner wall of respectively positioned one of the inner and outer halves of the housing 42. Each of the inner and outer the housing halves 42 have an opening 42c communicating with the respective retaining cups 42b. The sleeve 43 has a longitudinally extending size, passes the central hole 43c, aligned with the holes 43b of the inner and outer halves of the housing 42 and such as to receive a through bolt, which is entirely through the inner and outer halves of the housing. The nut 45a is screwed onto the threaded end portion of the screw 45 to clamp the inner and outer halves of the housing assembly 42, securely together with the 36 'and 36 ° discs freely rotating on the sleeve 43 and separated from each other by a washer 43d, and with the arm 40 'passing forward through the front portion of the slot 42e in the housing, and an arm 40' 'passing back through the rear portion of the slot in the housing. The arms 40 'and 40' 'are flat elongated plates.

[0037] As noted above, the disks 36 'and 36' 'of the 35' and 35 '' rotatable elements have their flat faces facing each other. This creates laterally adjacent parallel plates with elongated holes 41 'and 41' ', each having teeth of the respective one of the radial outer or inner gears 39' and 39 '' formed along part of the edge of the respective one of the elongated holes 41 'and 41' ' . The teeth of the radially outer rack 39 'of the disc 36' are formed along the radially outer edge of the elongated hole 41 ', and the teeth of the radially inner rack 39' 'of the disk 36' 'are formed along the radially inner edge of the elongated hole 41' '. Flat discs 36' and 36 '' are arranged in spaced parallel planes, and radially outer and inner gears 39 'and 39' 'are arranged similarly in spaced parallel planes and not in a common plane, or in direct connection with each other. The elongated holes 41 'and 41' 'are located on the disks 36' and 36 '' so as to at least partly overlap when rotating the 35 'and 35' 'rotating elements between the folded and unfolded state of the pushchair 10.

[0038]

Pinion 44 is located within the elongated holes 41 'and 41 "in simultaneous toothed engagement with both the radially outer rack 39' of the front rotary member 35 'and the radially inner rack 39' 'of the rear rotary member 35' '. Pinion 44 is positioned so that it passes through and out of each of the elongated holes 41 'and 41' 'of disks 36' and 36 '' in a position where the elongated holes overlap when folding and unfolding the pushchair 10, and extend fully between 39 'radially outer and inner gears

39 'discs

36 'and 36' in simultaneous connection with both teeth

<td>sprockets.</td><td>I don't think so</td><td> 44</td><td>moves</td><td>driving</td><td colspan="2">rotational force</td>

<td colspan="2">between the brackets</td><td> 20</td><td>front</td><td>wheel a and</td><td>supports</td><td> 24</td>

<td>handles co</td><td>causes</td><td>that</td><td colspan="2">one turns in</td><td>answers</td><td>on</td>

rotation of the second [0039] Pinion 44 is rotatably mounted on the mandrel

44a, each end portion of which extends beyond the pinion 44 located in the opening of the flat sleeve 44b and is rotatably held by the flat sleeve. Each of the flat sleeves 44b is disposed in and held by a retaining cup 44c formed by the inner wall of one of the inner and outer housing halves 42, respectively. The pinion 44 as such is supported by a housing 42 that is rigidly attached to the respective one of the rear wheel brackets 30 to move with it, of course, being rotatable about the axis of the stem 44a. With this arrangement, the pinion 44 is rotatable about a rotation axis and transverse to the plane of the 36 'and 36' 'discs, parallel to and away from the rotation axis of the 36' and 36 '' discs.

[0040] Pinion 44 engages with both the radially outer rack 39 'of the front rotary member 35' and the radially inner rack 39 '' of the rear rotary member 35 ''. In this regard, through pinion 44, radially outer rack 39 'and radially inner rack 39' 'are interconnected momentarily so that if one of them is rotated, the rotational force is transmitted by the pinion to the other to cause also revolved around sleeve 43. Thus, if the front wheel brackets 20 or the handle brackets 24 are rotated relative to the rear wheel brackets 30, the second element of the front wheel brackets and the handle brackets is driven to rotate as well.

[0041] The radially outer and inner gears 39 'and 39' 'have the same helical pitch, since the pinion 44 engages with both gears, but each has a larger pitch diameter than the pinion. However, the radially inner rack 39 '' has a smaller radius of curvature or pitch diameter than the radially outer rack 39 ', so the resulting rotational movement of the rear rotary member 35' 'will be greater than the rotational movement of the front rotary member 35'. In other words, for any amount of rotation of the pinion 44, the rear rotary member 35 '', and therefore the handle bracket 24, attached to it will rotate more than the front rotary member 35 '' and therefore the front wheel bracket 20 attached to it. This is useful because, as mentioned above, and as shown in Figure 4, to assemble the front wheel bracket 20 and the handle brackets tightly around the rear wheel brackets 30 a greater rotation angle is required for the handle brackets (in one embodiment about 108 °) than for the front wheel brackets (about 72 ° in the same embodiment). In another embodiment, the rotation angle of the handle brackets and the front wheel brackets is the same (in the second embodiment after about 90 °).

[0042] The pitch diameter for each of the radially outer rack 39 'of the front rotary member 35' and the radially inner rack 39 '' of the rear rotary member 35 '', and the pitch diameter of the pinion 44 are selected so as to obtain the desired ratio of front rotational movement and rear rotary element 35 'and 35' ', to fold the pushchair 10 into a compact form with the handle brackets 24 and the front wheel brackets 20 closely fitting the rear wheel brackets 30. However, although it is helpful to be able to choose different pitch diameters for the 39 'and 39' 'radial outer and inner rack, an even greater degree of design flexibility may be desirable.

[0043] In another embodiment of the folding assembly 22 shown in Figures 10 and 12, a pinion 44 'is shown having a first and second pinion portion 44x and 44y, the first pinion portion having a first helical pitch, a first pitch diameter and the first number of teeth, and the second part of the pinion has a different second helical pitch, a second pitch diameter and a different second number of teeth. The first and second parts 44x and 44y of the pinion are made as one part and rotate together as a concentric (coaxial) assembly on the shaft 44a, but are essentially two pinions each having their own teeth parameters. The first pinion part 44x is positioned to mesh with the 39 'radially outer rack and has a helix pitch corresponding to that rack and five teeth, and the second pinion portion 44y is positioned to engage the 39' 'radially inner rack helix pitch corresponding to this rack and four teeth. The first and second pinions 44x and 44y may have the same or different pitch diameters. In this way, the radially outer and inner rack 39 'and 39' 'and the first and second parts 44x and 44y of the pinion, which respectively mesh with each other, can be designed with tooth parameters that provide a wider range of differing amounts of front rotational movement and rear rotary element 35 'and 35' 'when folding and unfolding the pushchair 10. As a result, there is more design freedom and allowed flexibility because the pair of radially outer rack 39 'and the first pinion part 44x can be designed with the first teeth parameters to produce the first rotational movement of the front rotary member 35' and the pair of radially inner rack 39 '' and the second pinion parts 44y may be designed with different second tooth parameters, to produce a different second rotational movement of the rear 35 "rotating element, with independent selection of the parameters of the first and second teeth.

[0044] As noted above, in the described first embodiment of the invention, only the pitch diameters of the radially outer and radially inner rack 39 'and 39' 'differed, but in the example of Figures 10 and 12, the pair of radially outer and first part 44x of the tine and pair the radially inner rack 39 '' and the second pinion portion 44y can be designed substantially independently of each other to achieve the desired result, such as the desired embodiment of rack 39 ', the ratio of the rotational movement of the radially outer rack 39' and the radially inner rack 39 '', and thus the desired ratio of the rotational movement of the front and rear rotary elements 35 'and 35' ', when folding and unfolding the pushchair 10 . For example, this allows design of folding assemblies 22 with greater control of the amount of movement of both the handle brackets 24 and the front wheel brackets 20 relative to the rear wheel brackets 30 formed during folding the pushchair 10, and thus allows folding into a compact form, where the handle brackets and front wheel brackets can be moved so that they fit snugly against the rear wheel brackets.

[0045] In yet another embodiment of the folding assembly 22 shown in Figures 11 and 13, a pinion 44 '' is shown, having the first and second pinion 44xx and 44yy, made as separate parts but fixed together for rotation. together as an assembly on mandrel 44a, by welding, insertion pins or other means. Alternatively, the first and second pinion 44xx and 44yy may be spline-connected to the shaft 44a, as long as the shaft can rotate freely. The first pinion 44xx has a first helical pitch, the first pitch diameter and the first number of teeth (shown as five in this embodiment) and the second pinion 44yy has a different second helical pitch, the second pitch diameter and a different second number of teeth (shown as four in this embodiment). The first pinion 44xx is positioned to engage with the radially outer rack 39 'and the second pinion 44yy is positioned to engage with the radially inner rack 39' '. As above, a pair of radially outer rack 39 'and first rack 44x and a pair of radially inner rack 39' 'and second rack 44y can be designed with tooth parameters substantially independently of each other to achieve greater flexibility in the design of folding assemblies 22 to achieve the desired rotation ratio of the radially outer rack 39 'and the radially inner rack 39' ', and thus the desired ratio of the rotational movement of the front and rear 35 'and 35' 'rotational elements when folding and unfolding the pushchair 10.

[0046] The length of the radially outer rack 39 'of the front rotary member 35' and the radially inner rack 39 '' of the rear rotary member 35 '', as well as the length of the elongated holes 41 'and 41' 'in which the pinion 44 is located, affects the size of the possible rotation of the front and rear 35 'and 35' 'rotary elements. The range of motion is limited by bumpers 51 'and 51' 'attached to the peripheral part of the front and rear 35' and 35 '' rotary elements, respectively. Each of the bumpers 51 'and 51' 'extends laterally towards the adjacent rotational element and radially outside the periphery of the adjacent rotational element. The bumpers 51 'and 51 "are attached to the 35' and 35 '' rotational elements in positions along the periphery of the rotary element to which the bumpers are attached so that when the rotary elements are rotated to place the folding units 22 in the fully unfolded state, as shown in Figure 8, the bumpers 51 'and 51' 'are connected and prevent further rotation of the rotary elements in this direction of rotation. In the embodiment shown, the bumpers 51 'and 51' 'are positioned to allow a rotation angle of the handle brackets 24 of about 108 ° and front wheel brackets 20 of about 70 °.

[0047] It is understood that although in the illustrated embodiment the front wheel brackets 20 and the handle brackets 24 are attached to the rotatable elements 35 'and 35' 'folding assemblies 22 on the left and on the right (and rear wheel brackets 30 attached permanently to the housing 42), other embodiments may have rear wheel brackets 30 and handle brackets 24 attached to rotatable members 35 'and 35' 'folding assemblies 22 (and front wheel brackets 20 permanently attached to housing 42) such that they rotate to fold around the front wheel supports. Similarly, the rear wheel brackets 30 and the front wheel brackets 20 can be attached to the rotatable elements 35 'and 35' 'of the folding assemblies 22 (and the handle brackets 24 permanently attached to the housing 42) so that they rotate to fold around handle brackets.

[0048] To prevent unintentional folding, there are prams 10 when the folding assemblies 22 are in the fully unfolded state as shown in Figure 8, each folding assembly has a releasable locking mechanism with a slidably attached head 50 having a locking handle 52. The spring 54 applies pressure to the head 50 to keep the locking handle 52 in contact with the smooth, rounded peripheral portion of each of the folding assembly discs 36 'and 36' 'when the rotating elements are rotated near the fully unfolded state of the pushchair. The notches 38 'and 38' 'of the discs 36' and 36 '' are located along the reinforced peripheral part of the discs, in a place where, when the stroller 10 reaches the fully unfolded state, the notches are in line and the spring 54 will drive the head 50 forward, to place the locking handle 52 in both notches and thus prevent the discs from rotating towards the folded state. Part of the 36 'and 36' 'discs around the 38' and 38 '' notches have increased thickness for increased strength.

[0049] The head 50 is slidably mounted in the housing

42, in a position above the recess 42a in which the upper portion 30b of the free end of the rear wheel bracket 30 engages.

The upper end of the spring 54 connects to the head 50 and the lower end connects to the spring bracket 56 located inside the upper portion 30b of the free end of the rear wheel bracket 30. The lever 34 of the folding assembly 22 is pivotally mounted to the rear wheel bracket 30 and has a front portion passing through the hole in the head 50 and connected to the mandrel inside the head so that when the lever 34 is pulled up and inward as shown by arrows R1 on Figure 3, the head 50 is moved downward from the disks 36 'and 36' ', thus causing that the locking handle 52 is retracted from the notches 38 'and 38' 'and allowing the discs 36' and 36 '' to rotate towards the fully assembled state, shown in Figure 6, generally by moving the mussel shell to place the handle brackets 24 and the front brackets 20 the wheels in close contact with the rear wheel supports. The folding assembly 22 is shown in Figure 9 between the unfolded and folded states, with the locking handle 52 of the head 50 retracted from the notches 38 'and 38' '.

[0050] When the spring 54 provides sufficient force to the head 50 to keep the locking handle 52 in the notches 38 'and 38 ° to lock the pushchair 10 fully unfolded, this force is not so great that it requires excessive force to be applied to the lever 34 by the user to withdraw the locking handle from the notches when the folding assembly is to be folded.

[0051] Each of the folding assemblies 22 on the left and right has a corresponding left or right front wheel bracket 20 bolted to the arm 40 'of the front rotating member 35' and a corresponding left or right handle 24 bracket bolted to the 40 '' rear arm 35 '' rotary element.

[0052] It is understood that although rotatable elements

35 'and 35' 'are shown as including discs 36' and 36 '', in other embodiments, the rotatable elements 35 'and 35' 'may have different shapes.

[0053] Another embodiment of the all-terrain pushchair 10 'is shown in Figure 15. This embodiment has the basic same structure as the pushchair 10, but is designed to carry two children side by side. The frame 12 of the stroller 10 ', in addition to having frame brackets 24 on the left and right, has a central frame bracket 24' that extends upwards from the central folding assembly 22 '(shown in Fig. 14) of the same structure as the previously described folding assemblies 22, except that the central folding assembly 22 'has outwardly extending levers 34 on the left and right. Each of the levers of the central folding assembly 22 'can be pulled up and out to place the central folding assembly 22' in the unlocked state. As with the folding assembly 22 described above, each lever 34 of the central folding assembly 22 'is pivotally attached to the rear wheel bracket 30' and has a front portion passing through an opening in the head 50 of the central folding assembly 22, although from opposite sides thereof . The movement of each of the levers 34, when pulled up and out, causes the head 50 of the central folding assembly 22 'to move downward from the discs 36' and 36 '' of the central folding assembly 22, thereby causing, that the locking handle 52 is retracted from the 38 'and 38' 'notches and allows the disks 36' and 36 '' to rotate toward the fully folded state. The strap (not shown) can be connected with its ends to the lever 34 of the folding assembly 22 on the left, and to the lever

34, on the left, the central assembly 22 'for folding, and another strap (not shown) can be connected with its ends to the lever 34 of the folding assembly 22 on the right, and to lever 34, on the right, the central folding assembly 22 'to facilitate the movement of both levers with which the strap is connected at the same time.

[0054] From the above, it should be noted that although specific embodiments of the invention have been described herein for illustrative purposes, various modifications may be made without departing from the scope of the invention. Accordingly, the invention is not limited otherwise than by the appended claims.

BabyJogger, LLC

Proxy:

78P35994PL00

EP 1 744 941 B1