HK1172299B - Folding baby stroller - Google Patents

Abstract

The invention refers to a folding baby stroller and a folding mechanism used for the folding baby stroller. The baby stroller for transporting a child is disclosed. This baby stroller has a folding mechanism to facilitate folding for easier stowing and transporting. The folding mechanism, a unique feature of the design is directed toward compactness, ease of use, reliability, and reduction in manufacturing costs.

Description

Folding baby carriage

The present application is a divisional application of the invention patent application No. 200580013913.6, entitled "pushchair" with the filing date of 2005, 4/28.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the right of U.S. provisional patent application No. 60/567,325, filed on 30/4/2004, which provisional application is incorporated herein by reference in its entirety.

Technical Field

The present invention relates to strollers, and more particularly to a collapsible all-terrain stroller.

Background

Traditionally, strollers have been used to slowly propel an infant over a relatively hard and smooth floor or sidewalk. Therefore, the stroller is made small and lightweight. These strollers work well enough at slow speeds, but are extremely inflexible and even dangerous on rough roads or at higher speeds.

All-terrain strollers have been designed to overcome these problems. These strollers typically use much larger wheels, often large bicycle tires. The stroller frame members are constructed of metal tubing and durable plastic frame connectors or other durable materials to connect the frame members together for heavy duty use to which they may be subjected. The connector also serves to rotate or pivot one frame member relative to another frame member and to removably connect the other frame members together.

Some advanced designs for all-terrain strollers have made it possible to fold the all-terrain stroller to a lesser degree than desired in a compact size. In addition, conventional folding mechanisms include disadvantages of increased cost and reduced reliability and ease of use.

Disclosure of Invention

The present invention relates to a pushchair and a folding mechanism usable with the pushchair.

The folding mechanism includes a folding assembly having first and second rotatable members rotatably mounted for rotation relative to each other. A first rotatable member is positioned for rotation in a first plane of rotation and a second rotatable member is positioned for rotation in a second plane of rotation, the first and second planes of rotation being spaced apart. The first rotatable member has a first gear and the second rotatable member has a second gear. The folding assembly further has a third gear and a fourth gear configured to rotate together as a unit. The third gear is positioned in driving engagement with the fourth gear, and the fourth gear is positioned in driving engagement with the second gear such that the first rotatable member and the second rotatable member rotate relative to each other in geared coordination. The first rotatable member is configured for attachment to a first one of the first, second and third frame members, the second rotatable member is configured for attachment to a different second one of the first, second and third frame members, and the third and fourth gears are configured for support by another different third one of the first, second and third frame members.

The first gear of the folding mechanism may have a first pitch and the second gear has a second pitch different from the first pitch, and the third gear may have a third pitch compatible with the first pitch of the first gear and the fourth gear has a fourth pitch compatible with the second pitch of the second gear.

In one embodiment of the folding mechanism, the first rotatable member has a first aperture and the first gear is formed in a first edge portion of the first rotatable member defining the first aperture and the second rotatable member has a second aperture and the second gear is formed in a second edge portion of the second rotatable member defining the second aperture. The third gear is located in the first bore and the fourth gear is located in the second bore. The first and second edge portions may be radially displaced with respect to each other. Further, each of the first and second rotatable members may have a surface portion, wherein the surface portions are arranged in face-to-face juxtaposition.

The first and second rotatable members may be selectively mounted on the pivot member for rotation about a common axis of rotation, and the third and fourth gears may be coaxially mounted for rotation about an axis parallel to and spaced from the common axis of the first and second rotatable members.

In one embodiment of the folding mechanism, the third gear has a first number of gear teeth and the fourth gear has a second number of gear teeth different from the first number, and the third gear has a pitch compatible with the pitch of the first gear and the fourth gear has a pitch compatible with the pitch of the second gear.

The folding assembly may be used as part of a pushchair frame or other device. Strollers typically have a front wheel support, a rear wheel support, and a handle member. The folding assembly may include pivoting members, first rotatable members having a first aperture containing a first gear, second rotatable members having a second aperture containing a second gear. The first and second rotatable members are rotatably coupled to the pivoting member for rotation about a common axis of rotation. A third gear is located in the first and second bores in driving engagement with the first and second gears such that the first and second rotatable members rotate relative to each other in geared coordination.

The first gear may have a first pitch and the second gear may have a second pitch different from the first pitch, and the third gear may include a first gear portion having the first pitch and a second gear portion having the second pitch. The first and second portions of the third gear are configured to rotate as a unit. The first gear portion of the third gear is located in the first bore in driving engagement with the first gear and the second gear portion of the third gear is located in the second bore in driving engagement with the second gear.

The pivot member is configured to be supportingly engaged by one of the front wheel support, the rear wheel support, and the handle member, the second rotatable member is configured to be attached to a different one of the front wheel support, the rear wheel support, and the handle member, and the second rotatable member is configured to be attached to a different one of the front wheel support, the rear wheel support, and the handle member.

The first gear is formed in a first edge portion of the first rotating member defining the first aperture, and the second gear is formed in a second edge portion of the second rotating member defining the second aperture. In the depicted embodiment, the first and second edge portions are radially displaced relative to each other.

The first and second apertures may be elongated, wherein the elongated first and second apertures at least partially overlap. The first gear has a first pitch diameter and the second gear has a second pitch diameter, wherein the first pitch diameter and the second pitch diameter are not the same. The first gear may be located radially outward of the second gear.

The depicted embodiment has the first pitch diameter of the first gear sized to rotate one of the front wheel support, the rear wheel support and the handle member on which the first rotatable member is configured to attach from the folded position to the unfolded position of the pushchair frame through a first angle of rotation, and the second pitch diameter of the second gear sized to rotate one of the front wheel support, the rear wheel support and the handle member on which the second rotatable member is configured to attach from the folded position to the unfolded position of the pushchair frame through a second angle of rotation, wherein the first and second angles of rotation are not the same.

The first rotatable member has an arm configured to be attached to one of the front wheel support, the rear wheel support, and the handle member, wherein the first rotatable member is configured to be attached to the one, and the second rotatable member has an arm configured to be attached to one of the front wheel support, the rear wheel support, and the handle member, wherein the second rotatable member is configured to be attached to the one.

The folding assembly may comprise a movable member and each of the first and second rotatable members may further comprise a recess in which the movable member is receivable when the first and second rotatable members are rotated about the pivot member to a position in which the recesses of the first and second rotatable members are in alignment.

The folding assembly may also include a housing in which the pivot member may be located. The housing is configured to be attached to one of a front wheel support, a rear wheel support, and a handle member, while the pivoting member is configured to be in supporting engagement therewith.

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

Drawings

Fig. 1 is an isometric view of an exemplary embodiment of a stroller embodying the present invention shown in a fully deployed, ready to use state.

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

Fig. 3 is a front view of the stroller of fig. 2.

Fig. 4 is a side view of the stroller of fig. 2.

Fig. 5 is a side view of the stroller frame of fig. 2 shown in a partially folded condition.

Fig. 6 is a side view of the stroller frame of fig. 2 shown in a fully folded state with the left and right front supports and the left and right side handle supports rotated about their respective side folding assemblies toward their respective side rear wheel supports and the front wheels removed.

FIG. 7 is an exploded isometric view of the right side folding assembly of the embodiment shown in FIG. 1, with the left side folding assembly being a mirror image thereof.

FIG. 8 is a right side view of an enlarged portion of the right side folding assembly of FIG. 7 with the outer half shell of the assembly removed and in a fully folded condition.

FIG. 9 is a left side view of a portion of the right side folding assembly of FIG. 7 with the inner housing half removed and in a partially unfolded state.

Fig. 10 is an enlarged isometric view of a pinion and pin used in an alternative embodiment of the folding assembly shown in fig. 12. Wherein the pinion has two gear portions.

FIG. 11 is an enlarged isometric view of a pinion and pin used in another alternative embodiment of the folding assembly shown in FIG. 13, wherein the pinion includes two gears that are secured together for use.

FIG. 12 is an exploded isometric view corresponding to FIG. 7 showing a right side folding assembly of an alternative embodiment of a folding assembly, wherein the left side folding assembly is a mirror image thereof.

FIG. 13 is an exploded isometric view corresponding to FIG. 7 showing a right side folding assembly of another alternative embodiment of a folding assembly, wherein the left side folding assembly is a mirror image thereof.

Fig. 14 is an exploded isometric view corresponding to fig. 7, showing the central folding assembly used in the tandem stroller shown in fig. 15 with two release bars in fig. 15.

Fig. 15 is an isometric view of an exemplary embodiment of a tandem stroller embodying the present invention shown in a fully deployed, ready-to-use condition, but without the seat and leg guards.

Detailed Description

As shown in the drawings for purposes of illustration, the present invention is embodied in a full-service stroller 10 as shown in fig. 1 having a collapsible tubular metal frame 12 and a transversely extending rear axle assembly 14, wherein the rear axle assembly 14 has a transverse non-rotating tubular rear axle 15. Left and right side rear wheels 16 are rotatably mounted to the ends of the rear axle assembly 14. The front end of the frame 12 has a single front wheel 18 rotatably mounted thereto.

The frame 12 does not have a base frame member that extends rearwardly from the front wheel 18 to the rear axle assembly 14 as most conventional full-road strollers. Instead, the frame 12 includes left and right side downwardly and forwardly inclined front wheel frame members or supports 20, each of which extends downwardly in a converging configuration from a corresponding one of the left and right side folding assemblies 22 to the front wheel 18. The front free end 20a of each of the left and right side front wheel supports 20 has a plastic front wheel connector 20b fixedly attached thereto and a corresponding one of the left and right ends of the axle 18a of the front wheel 18 removably attached thereto so that the front wheel can be mounted to the stroller frame 12.

The front wheel supports 20 are interconnected by a foot board 23 which spans between the supports, towards but rearward of their front free ends 20a, and is fixedly attached to each support at a location rearward of the axle 18a of the front wheel and extends partially over the front wheel 18. Due to the interconnection provided by the front wheels 18 when the front wheels 18 are attached to the left and right side front wheel connectors and the foot board 23, the left and right side front wheel supports 20 form a stationary unit relative to the left and right side folding assemblies 22 when the stroller 10 is folded and unfolded, as described in more detail below.

The frame 12 also includes left and right side upwardly and downwardly sloping handle frame members or supports 24, each of which extends upwardly from a corresponding one of the left and right side folding assemblies 22 in a generally parallel configuration to a handle 26 extending between the left and right side handle supports. The handle 26 is covered by a grip made of foam material. The handle supports 24 are interconnected by a handle 26, which handle 26 spans between the handle supports at their rearmost and uppermost extensions and is fixedly attached to each handle support.

Due to the interconnection provided by the handles 26, the left and right side handle supports 24 move as a unit relative to the left and right side folding assemblies 22 when folding and unfolding the stroller 10, as described in more detail below. It should be noted that instead of interconnecting the handles 26, each handle support 24 may be provided at its upper end with a handle portion as used in umbrella strollers.

In the illustrated embodiment of the invention, the left and right side handle supports 24 and the handle 26 are formed as an integral unit by bending a single length of aluminum tubing. The left and right side handle supports 24 are movable relative to the left and right side front wheel supports 20 to fold the stroller 10 and do not together form an integral rigid upper frame.

The frame 12 also includes left and right side downwardly and rearwardly inclined rear wheel frame members or supports 30, each of which extends downwardly from a corresponding one of the left and right side folding assemblies 22 in a generally parallel configuration to the rear axle assembly 14. The rear free end 30a of each of the left and right side rear wheel supports 30 is fixedly attached to the tubular rear wheel shaft 15 toward the corresponding one of the left and right ends of the tubular rear wheel shaft 15. The rear wheel supports 30 are interconnected by a rear axle assembly 14, the rear axle assembly 14 spanning between the supports at their rear free ends 30 a. A U-shaped cross member 31 extends between the left and right side rear wheel supports 30. Due to the interconnection provided by the rear axle assembly 14 and the cross-frame member 31, the left and right side rear wheel supports 30 move as a unit relative to the left and right folding assemblies 22 to fold and unfold the stroller 10, as described in more detail below. The left and right side rear wheel supports 30 are also movable relative to the left and right side front wheel supports 20 and the left and right side handle supports 24 to fold the stroller 10. Furthermore, the left and right side rear wheel supports 30 and the rear axle assembly 14 connected thereto do not form part of a base frame extending between the rear wheel 16 and the front wheel 18. The structural strength of the stroller 10 and the interconnection of the front wheel support 20, the handle support 24, and the rear wheel support 30 is provided in large part by the centrally located left and right side folding assemblies 22, rather than by the base frame.

In the illustrated embodiment of the stroller 10, the left and right side front wheel supports 20, the left and right side handle supports 24, and the left and right side rear wheel supports 30 are made of aluminum tubing. Suitable alternative materials may also be used.

The left and right outer ends of the tubular rear wheel axle 15 are open and internally threaded to receive a threaded stub wheel axle 32, the stub wheel axle 32 forming part of a corresponding one of the left and right rear wheels 16. A locking nut (not shown) when locked against a surface of the stub axle 32 may lock the stub axle against loosening during use of the stroller 10. Alternative constructions may be used to fixedly or removably attach the rear wheel 16 to the tubular rear axle 15, and any suitable alternative for mounting the rear wheel 16 to the rear wheel support 30 may also be used.

The frame 12 of the stroller 10 is shown in fig. 1 in a fully deployed state with the seat 33a and leg support and protection 33b made of fabric. The seat 33a is suspended from the left and right side handle supports 24, and the leg protector 33b spans between the left and right side front wheel supports 20 and is supported by the front wheel supports 20. For purposes of illustration, the frame 12 is shown in FIG. 2 without the seat 33a and the leg guard 33 b.

For the depicted embodiment, the user's operation of the left and right side folding assemblies 22 will now be described. The left and right side folding assemblies 22 are of identical construction, one being a mirror image of the other, and the following description, although in singular form, will apply to both. When the frame 12 of the stroller 10 is locked in the fully deployed position, each of the left and right rear wheel supports 30 supports an inwardly extending bar 34, the bar 34 having a primarily vertical orientation as shown in fig. 3. To begin the process of folding the frame 12, each lever 34 is pulled upwardly and inwardly as depicted by arrow R1, thereby placing the left and right side folding assemblies 22 in an unlocked condition, as explained further below. A strap (not shown) may be connected to the rods 34 by their ends to facilitate simultaneous movement of the two rods.

When each of the left and right side folding assemblies 22 is in an unlocked state, the left and right side handle supports 24, along with the handle 26 and the left and right front wheel supports 20, along with the front wheel 18, can be rotated about the left and right side folding assemblies, respectively, toward the left and right rear wheel supports 30, respectively, as depicted by arrow R2 in fig. 4. As shown, the folding assembly 22 allows the handle supports 24 to rotate a greater angle (greater than 90 °) than the front wheel supports 20 when the stroller 10 is folded. As explained further below, the front wheel support 20 moves in geared coordination with movement of the handle support 24. When the frame 12 is folded, the front wheel support 20 rotates clockwise about the folding assembly 22 as viewed in FIG. 4, and the handle support 24 also rotates counterclockwise about the folding assembly as viewed in FIG. 4. The frame 12 is shown in a partially folded condition in fig. 5. In a fully folded state, the front wheel supports 20 and the handle supports 24 rotate in geared coordination with each other about the folding assembly 22 so as to be positionable in close proximity to the rear wheel supports 30 as shown in FIG. 6. To this end, the front wheel 18 is removed.

The right side folding assembly 22 is shown in an exploded view in fig. 7 and includes a laterally outwardly positioned front rotatable member 35' and a laterally inwardly positioned rear rotatable member 35 ", each having flat faces facing toward each other. The front rotatable member 35 ' includes a plate or disc 36 ' having a central plate portion with a central aperture 37 '. The front rotatable member 35 ' further includes a notch 38 ', a radially outward inner gear 39 ' located in the elongated aperture 41 ', and an arm 40 '. The rear rotatable member 35 "has a plate or disc 36" with a central plate portion having a central aperture 37 ". The rear rotatable member 35 "also includes a notch 38", an inner gear 39 "located radially inwardly of the elongated aperture 41", and arm portions 40 ". For each of the rotatable members 35 ' and 35 ", the disks 36 ' and 36" and the arms 40 ' and 40 "are depicted as being formed as part of a single flat piece; however, in other embodiments, the disk and the arm are separate pieces fixedly connected together.

The rotatable members 35 'and 35 "are contained between the inner and outer grooved halves of the housing 42, along with corresponding ones of the rear wheel supports 30, which allow the arms 40' and 40" to extend outside of the housing. The inner wall of each half of the housing 42 has a recess 42a sized and shaped such that when the two halves of the housing are placed together, the recess forms a cavity to receive therein an upper free end portion 30b of the respective rear wheel support 30 and an upper free end portion of the cross member 31. A bolt (not shown) extends through the aperture 42f in each half of the housing 42 and through the aperture 30c in the upper free end 30b of the rear wheel support 30 and the aperture in the upper free end portion of the cross member 31 to firmly clamp the rear wheel support and cross member between the inner and outer halves of the housing.

The central apertures 37 'and 37 "of the disks 36' and 36", respectively, are sized to receive a bushing 43 therethrough having a length that is greater than the combined thickness of the two disks. The rotatable members 35 'and 35 "are rotatably mounted on the bushing for rotation within the housing 42 in parallel planes of rotation about an axis of rotation transverse to the plane of the disks 36' and 36". Each end of the bushing extending beyond the central bores 37' and 37 "has an annular groove 43a to receive a C-clip 43b to hold the bushing 43 in place. The bushing 43 also extends through a washer 43d, and the washer 43d is located between the disks 36 'and 36 "of the rotatable members 35' and 35" to act as a spacer and bearing surface for rotational movement of the rotatable members about the bushing 43. The disks 36' and 36 "each have a flat face that is juxtaposed face-to-face with the flat face of the other disk with the washer 43d therebetween.

The ends of the bushings 43 that extend beyond the C-clip 43b are each seated in and retained by a retaining cap 42b, which retaining cap 42b is formed by the inner side walls of a correspondingly positioned one of the inner and outer halves of the housing 42. Each of the inner and outer halves of the housing 42 has a hole 42c communicating with the corresponding fixing cap 42 b. The bushing 43 has a longitudinally extending central bore 43c that is aligned with the bores 43b in the inner and outer halves of the housing 42 and is sized to receive a bolt 45 therethrough, the bolt 45 extending completely through the inner and outer halves of the housing. Nuts 45a are threaded onto the threaded ends of the bolts 45 so that the inner and outer halves of the housing 42 of the folding assembly 22 can be securely clamped together with the discs 36 'and 36 "free to rotate on the bushings 43 and separated by the washers 43d, and so that the arms 40' extend forwardly through the front of the slots 42e in the housing and the arms 40" extend rearwardly through the rear of the housing slots. The arms 40' and 40 "are flat elongated plates.

As described above, the disks 36 'and 36 "of the rotatable members 35' and 35" have their flat faces juxtaposed face to face. This provides laterally adjacent parallel plates having elongated apertures 41 ' and 41 ", each elongated aperture 41 ' and 41" having gear teeth of a respective one of the radially outward and inward gears 39 ' and 39 ", the gears 39 ' and 39" being formed along an edge portion of the respective one of the elongated apertures 41 ' and 41 ". The gear teeth of the radially outward gear 39 ' of the disc 36 ' are formed along the radially outward edge of the elongated hole 41 ', and the gear teeth of the radially inward gear 39 "of the disc 36" are formed along the radially inward edge of the elongated hole 41 ". The planar disks 36 'and 36 "are arranged in spaced parallel planes and the radially outward and inward gears 39' and 39" are similarly arranged in spaced parallel planes but not in a common plane or directly engaging each other. The elongated apertures 41 ' and 41 "are located on the disks 36 ' and 36" so as to at least partially overlap during rotation of the rotatable members 35 ' and 35 "between the folded and unfolded states of the stroller 10.

The pinion gear 44 is located within the elongated apertures 41 ' and 41 "in gear engagement with the radially outwardly facing gear 39 ' of the forward rotatable member 35 ' and the radially inwardly facing gear 39" of the rearward rotatable member 35 ". The pinion gear 44 is positioned to extend through and over each of the elongated apertures 41 'and 41 "of the disks 36' and 36" at a location where the elongated apertures overlap during folding and unfolding of the stroller 10, and completely spans between the radially outward and inward facing gears 39 'and 39 "of the disks 36' and 36" while forming a gear mesh with both gears. The pinion gear 44 transmits a driving rotational force between the front wheel support 20 and the handle support 24, which enables one to rotate in response to rotation of the other.

The pinion gear 44 is rotatably mounted to a pin 44a, with each end of the pin 44a extending beyond the pinion gear 44 positioned within a hole of a flat bushing 44b and secured by the flat bushing. Each flat bushing 44b is positioned in and secured by a retaining cap 44c, which retaining cap 44c is formed by the inner side walls of a correspondingly positioned one of the inner and outer halves of the housing 42. Thus, the pinion gear 44 is supported by the housing 42 which is rigidly attached to a corresponding one of the rear wheel supports 30 for movement therewith, although the pinion gear 44 may rotate about the axis of the pin 44 a. With this arrangement, the pinion gear 44 is rotatable about an axis of rotation transverse to the plane of the disks 36 'and 36 ", and the axis of rotation is parallel to and spaced from the axis of rotation of the disks 36' and 36".

The pinion gear 44 engages the radially outward gear 39 'of the front rotatable member 35' and the radially inward gear 39 "of the rear rotatable member 35". Subsequently, the radially outward gear 39' and the radially inward gear 39 ″ are mutually drivingly engaged with each other by the pinion gear 44, so that if either is rotated, the rotational force will be transmitted to the other through the pinion gear, so that the other is also rotated about the hub 43. Thus, if either the front wheel supports 20 or the handle supports 24 are rotated relative to the rear wheel supports 30, the other of the front wheel supports and the handle supports is also driven to rotate.

The radially outward and inward gears 39' and 39 "have the same pitch because the pinion gear 44 engages both, but each has a larger pitch diameter than the pinion gear. However, the radially inward gear 39 "has a smaller radius of curvature or pitch diameter than the radially outward gear 39 ', and thus the resulting rotational movement of the rear rotatable member 35" will be greater than the rotational movement of the front rotatable member 35'. In other words, regardless of how many pinions 44 are rotated, rear rotatable member 35 ", with handle supports 24 attached thereto, will rotate more than front rotatable member 35', with rear wheel supports 24 attached thereto. As noted above and as shown in fig. 4, this is useful because to fold the front wheel supports 20 and the handle supports 24 tightly around the rear wheel supports 30 requires the handle supports to have a greater angle of rotation (in one embodiment about 108 °) that is greater than the angle of rotation of the front wheel supports (in the same embodiment about 72 °). In another embodiment, the angle of rotation of the front wheel support and the handle support are the same (about 90 ° each in the second embodiment).

The pitch diameter of each of the radially outward gear 39 ' of the front rotatable member 35 ' and the radially inward gear 39 "of the rear rotatable member 35" and the pitch diameter of the pinion gear 44 are selected to produce the desired ratio of rotational movement of the front and rear rotatable members 35 ' and 35 "in order to fold the stroller 10 into a compact form with the handle supports 24 and the front wheel supports 20 securely nested against the rear wheel supports 30. However, while the ability to select different pitch diameters for the radially outward and inward gears 39' and 39 "is helpful, a greater degree of design flexibility may be more desirable.

In another embodiment of the folding assembly 22 as shown in fig. 10 and 12, the pinion gear 44' is shown having first and second pinion gear portions 44x and 44y, with the first pinion gear portion having a first pitch, a first pitch diameter and a first number of gear teeth, and the second pinion gear portion having a different second pitch, a second pitch diameter and a different second number of gear teeth. The first and second pinion gear portions 44x and 44y are manufactured as a single component and rotate as a unit in a coaxial arrangement on the pin 44a, but are essentially two pinions each having its own gear parameters. The first pinion gear portion 44x is positioned to engage the radially outward gear 39' and has a pitch corresponding thereto and five gear teeth, and the second pinion gear portion 44y is positioned to engage the radially inward gear 39 "and has a pitch corresponding thereto and four gear teeth. The first and second pinion gear portions 44x and 44y may have the same or different pitch diameters. In this manner, the radially outward and inward gears 39 'and 39 ", along with the first and second pinion gear portions 44x and 44y that mesh therewith, respectively, may be designed, depending on the gear parameters, to produce a wide range of different amounts of rotational movement of the front and rear rotatable members 35' and 35" when folding and unfolding the stroller 10. In fact, there is more design freedom and flexibility allowed, since the radially outward gear 39 'and first pinion gear portion 44x pair can be designed to produce a first rotational movement of the forward rotatable member 35' according to a first gear parameter, and the radially inward gear 39 "and second pinion gear portion 44y pair can be designed to produce a second, different rotational movement of the rearward rotatable member 35" according to a second, different gear parameter, wherein the first and second gear parameters selected are independent.

As noted above, the first described embodiment differs only in the pitch diameters of the radially outward and inward gears 39 'and 39 ", but in the embodiment of FIGS. 10 and 12, the radially outward gear 39' and first pinion gear portion 44x pairing and the radially inward gear 39" and second pinion gear portion 44y pairing can be designed to be substantially independent of the other so that a desired result can be produced when folding and unfolding the stroller 10, such as producing a desired ratio of rotational movement of the radially outward gear 39 'to the radially inward gear 39 ", and thus the front and rear rotatable members 35' and 35". For example, this allows the design of the folding assembly 22 to have more control over the amount of movement of both the handle supports 24 and the front wheel supports 20 relative to the rear wheel supports 30 that results during folding of the stroller 10, and thus allows folding into a compact form in which the handle supports and the front wheel supports move into a secured nest against the rear wheel supports.

In another embodiment of the folding assembly 22 as shown in fig. 11 and 13, the pinion gear 44 "is shown as having first and second pinion gears 44xx and 44yy that are made as separate pieces but are fixedly connected together by welding, a bayonet, or some other means to rotate as a unit on pin 44 a. Alternatively, the first and second pinions 44xx and 44yy may be disposed in the key grooves of the pin 44a as long as the pin is freely rotatable. The first pinion 44xx has a first pitch, a first pitch diameter, and a first number of gear teeth (five are shown in this embodiment), and the second pinion 44yy has a different second pitch, a second pitch diameter, and a different second number of gear teeth (four are shown in this embodiment). The first pinion gear portion 44xx is positioned to engage the radially outward gear 39' and the second pinion gear portion 44yy is positioned to engage the radially inward gear 39 ". As previously described, the radially outward gear 39 ' and first pinion gear portion 44xx pairing and the radially inward gear 39 "and second pinion gear portion 44yy pairing can be designed with gear parameters substantially independent of the other to provide greater flexibility in designing the folding assembly 22 to produce a desired ratio of rotational movement of the radially outward gear 39 ' and the radially inward gear 39" and thus a desired ratio of rotational movement of the front and rear rotatable members 35 ' and 35 "when folding and unfolding the stroller 10.

The length of the radially outward gear 39 'of the forward rotatable member 35' and the radially inward gear 39 "of the rearward rotatable member 35", and the length of the elongated apertures 41 'and 41 "within which the pinion gear 44 is positioned, will likely affect the amount of rotation of the forward and rearward rotatable members 35' and 35". The range of movement is limited by stops 51 'and 51 "attached to peripheral portions of the front and rear rotatable members 35' and 35", respectively. Each of the stops 51' and 51 "extends laterally toward and radially outward of the periphery of the adjacent rotatable members. The stops 51 ' and 51 "are attached to the rotatable members 35 ' and 35" at locations along the periphery of the rotatable members to which they are attached such that when the rotatable members are rotated to place the folding assembly 22 in the fully unfolded state as shown in fig. 8, the stops 51 ' and 51 "engage and prevent further rotational movement of the rotatable members in the direction of rotation. In the depicted embodiment, the stops 51' and 51 "are positioned to allow for a rotation angle of the handle support 24 of about 108 ° and a rotation angle of the front wheel support 20 of about 70 °.

It should be understood that while the front wheel supports 20 and handle supports 24 are attached to the rotatable members 35 'and 35 "of the left and right side folding assemblies 22 in the depicted embodiment (and the rear wheel supports 30 are fixedly attached to the housing 42), other embodiments may have the rear wheel supports 30 and handle supports 24 attached to the rotatable members 35' and 35" of the folding assemblies 22 (and the front wheel supports 20 fixedly attached to the housing 42) so that they can be folded rotationally about the front wheel supports. Similarly, the rear wheel support 30 and the front wheel support 20 may be attached to the rotatable members 35' and 35 "of the folding assembly 22 (and the handle support 24 fixedly attached to the housing 42) such that they can be folded rotationally about the handle support.

To prevent inadvertent folding of the stroller 10 when the folding assemblies 22 are in the fully unfolded condition shown in fig. 8, each folding assembly has a releasable locking mechanism with a slidably mounted head piece 50 having a locking tab 52. The spring 54 applies a biasing force to the head piece 50 to maintain the locking tab 52 in contact with the smooth circular perimeter of each of the discs 36' and 36 "of the folding assembly as the rotatable members are rotated to approximate the fully deployed state of the stroller. The notches 38 'and 38 "of the disks 36' and 36" are positioned along the reinforced peripheral portion of the disks at a location where the notches are in alignment when the stroller 10 reaches the fully deployed condition, and the spring 54 urges the head 50 forward to position the locking tabs within the two notches and thus prevent the disks from rotating to the collapsed condition. The portions of the disks 36 'and 36 "surrounding the notches 38' and 38" have an increased thickness for increased strength.

The head piece 50 is slidably mounted in the housing 42 at a position above a recess 42a, which recess 42a receives the upper free end portion 30b of the rear wheel support 30. The upper end of the spring 54 engages the head piece 50 and the lower end engages a spring support 56 located inside the upper free end portion 30b of the rear wheel support 30. The lever 34 of the folding assembly 22 is pivotally mounted to the rear wheel support 30 and has a nose which extends through a hole in the headpiece 50 and engages a pin in the headpiece such that when the lever 34 is pulled upwardly and inwardly as depicted by arrow R1 in fig. 3, the headpiece 50 will move downwardly away from the disks 36 ' and 36 "thereby causing the locking tabs 52 to be withdrawn from the notches 38 ' and 38" and allowing the disks 36 ' and 36 "to rotate in a generally clam-shell like movement to a fully extended condition as shown in fig. 6 to position the handle support 24 and the front wheel support 20 with the fastening sleeve nested against the rear wheel support 30 in place. The folding assembly 22 is shown in fig. 9 between an unfolded and folded position with the locking tabs 52 of the headpiece 50 retracted from the notches 38' and 38 ".

While the spring 54 provides sufficient force to the head piece 50 to retain the locking tab 52 within the notches 38' and 38 "to lock the stroller 10 in the fully unfolded state, the force is not so great that the user needs to apply excessive force to the lever 34 to retract the locking tab from the notch when the folding assembly is to be folded.

Each of the left and right folding assemblies 22 has a corresponding left or right front wheel support 20 bolted to the arm 40 'of the front rotatable member 35' and a corresponding left or right handle support 24 bolted to the arm 40 "of the front rotatable member 35".

It should be appreciated that while rotatable members 35 ' and 35 "are depicted as including disks 36 ' and 36", rotatable members 35 ' and 35 "may have other shapes in other embodiments.

Fig. 15 shows another embodiment of a full-road condition stroller 10'. This embodiment has substantially the same design as the stroller 10, but is designed to carry two children disposed side-by-side. In addition to having left and right side frame supports 24, the frame 12 of the stroller 10 'also has a central frame support 24' that extends upwardly from a central folding assembly 22 '(as shown in fig. 14), and the central folding assembly 22' has the same structure as the previously described folding assembly 22, except that it has left and right side extension bars 34. Either lever of the central folding assembly 22 'can be pulled upwardly and outwardly to place the central folding assembly 22' in a released state. Much the same as the folding assemblies 22 described above, each lever 34 of the central folding assembly 22 ' is pivotally mounted to a rear wheel support 30 ' and has a nose portion that extends through an aperture in the head 50 of the central folding assembly 22 ', however each lever extends from opposite sides of the head. Movement of either lever 34 when pulled upwardly and outwardly causes the head 50 of the central folding assembly 22 ' to move downwardly away from the disks 36 ' and 36 "of the central folding assembly 22 ', causing the locking tabs 52 to be withdrawn from the notches 38 ' and 38" and allowing the disks 36 ' and 36 "to rotate to a fully extended state. One strap (not shown) may be attached by its ends to the lever 34 of the left side folding assembly 22 and the left side lever 34 of the center folding assembly 22 ', while the other strap (not shown) may be attached by its ends to the lever 34 of the right side folding assembly 22 and the right side lever 34 of the center folding assembly 22', to facilitate simultaneous movement of the two levers to which the straps are connected.

From the foregoing, it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited to the foregoing embodiments, except as defined by the following claims.

Claims (16)

1. A pushchair, comprising:

a front wheel;

left and right laterally spaced apart front wheel supports, each of said left and right side front wheel supports having a front end and a rear end, said front wheel being mounted to said front end of at least one of said front wheel supports, said left and right side front wheel supports being rotatable as a unit;

left and right rear wheels;

left and right laterally spaced rear wheel supports, each of the left and right rear wheel supports having a lower end coupled to at least one of the left and right rear wheels and an upper end;

left and right laterally spaced handle features, each of said left and right handle features having a front end and a rear end with a handle portion, said left and right handle features being rotatable as a unit; and

left and right laterally spaced folding assemblies, each of said left and right side folding assemblies having a first rotatable member and a second rotatable member rotatably coupled to a pivot member supported by the upper end of a corresponding one of said left and right rear wheel supports for rotation about a common axis of rotation, said first rotatable member having a first elongated aperture containing a first gear and said second rotatable member having a second elongated aperture containing a second gear, said first rotatable member and said second rotatable member having flat faces in face-to-face juxtaposition to provide laterally spaced parallel plates having said first and second elongated apertures, each of said left and right side folding assemblies further having a third gear in both said first and second elongated apertures and in communication with said first gear and said second gear Driving engagement such that the first rotatable member and the second rotatable member rotate relative to each other in geared coordination, the rear end of a corresponding one of the left and right side front wheel supports being attached to the first rotatable member and the front end of a corresponding one of the left and right side handle members being attached to the second rotatable member, the first rotatable member being positioned to rotate in a first plane of rotation and the second rotatable member being positioned to rotate in a second plane of rotation spaced from the first plane of rotation.

2. The foldable stroller of claim 1, wherein the first gear is formed in a radially outward edge portion of the first rotatable member of each of the left and right side folding assemblies defining the first elongated aperture and the second gear is formed in a radially inward edge portion of the second rotatable member of each of the left and right side folding assemblies defining the second elongated aperture.

3. The foldable stroller of claim 1, wherein the front wheel support rotates from a folded position to an unfolded position of the foldable stroller through a first angle of rotation and the handle member rotates from the folded position to the unfolded position of the foldable stroller through a second angle of rotation, wherein the first and second angles of rotation are not the same, and wherein the first gear of each of the left and right side folding assemblies has a first pitch diameter and the second gear of each of the left and right side folding assemblies has a second pitch diameter, wherein the first pitch diameter is not the same as the second pitch diameter, the first pitch diameter being sized relative to the second pitch diameter to allow the front wheel support to rotate through the first angle of rotation, and the handle member is rotated through the second angle of rotation.

4. The foldable stroller of claim 1, wherein the first gear has a first pitch and the second gear has a second pitch different from the first pitch, and wherein the third gear comprises a first gear portion having the first pitch and a second gear portion having the second pitch, the first and second portions of the third gear being configured to rotate as a unit, and the first gear portion of the third gear being located in the first elongated aperture and in driving engagement with the first gear, and the second gear portion of the third gear being located in the second elongated aperture and in driving engagement with the second gear.

5. The foldable stroller of claim 1, wherein the first gear has a first pitch and the second gear has a second pitch that is the same as the first pitch, and wherein the third gear comprises a first gear portion having the first pitch and a second gear portion having the second pitch, the first and second portions of the third gear rotate as a unit, and the first gear portion of the third gear is located in the first elongated aperture and in driving engagement with the first gear, and the second gear portion of the third gear is located in the second elongated aperture and in driving engagement with the second gear.

6. A folding mechanism for use with a folding device having first, second and third frame members, comprising:

a first rotatable member having a first gear;

a second rotatable member having a second gear, wherein the first rotatable member has a first aperture and the second rotatable member has a second aperture, the first rotatable member and the second rotatable member having planar faces in face-to-face juxtaposition to provide laterally spaced parallel plates having the first and second apertures, and wherein the second rotatable member is rotatably mounted for rotation relative to the first rotatable member, the first rotatable member positioned for rotation in a first plane of rotation and the second rotatable member positioned for rotation in a second plane of rotation spaced from the first plane of rotation;

a third gear and a fourth gear configured to rotate as a unit, the third gear positioned to be in driving engagement with the first gear and the fourth gear positioned to be in driving engagement with the second gear such that the first rotatable member and the second rotatable member rotate in geared coordination with each other, the first rotatable member configured to be attached to a first one of the first, second, and third frame members, the second rotatable member configured to be attached to a different, second one of the first, second, and third frame members, and the third and fourth gears configured to be supported by a different, third one of the first, second, and third frame members.

7. The folding mechanism of claim 6 wherein the first gear has a first pitch and the second gear has a second pitch different from the first pitch, and wherein the third gear has a third pitch compatible with the first pitch of the first gear and the fourth gear has a fourth pitch compatible with the second pitch of the second gear.

8. The folding mechanism of claim 7 wherein the first gear is formed at a first edge portion of the first rotatable member defining the first aperture and the second gear is formed at a second edge portion of the second rotatable member defining the second aperture, and wherein the third gear is located in the first aperture and the fourth gear is located in the second aperture.

9. The folding mechanism of claim 8 wherein the first and second edge portions are radially displaced from one another.

10. The folding mechanism of claim 6 wherein the third gear has a first gear tooth count and the fourth gear has a second gear tooth count different from the first gear tooth count, and wherein the third gear has a pitch compatible with the pitch of the first gear and the fourth gear has a pitch compatible with the pitch of the second gear.

11. The folding mechanism of claim 6 wherein the first gear is sized to rotate the first rotatable member through a first angle of rotation from a folded position to an unfolded position, and wherein the second pitch diameter of the second gear is sized to rotate one of a front wheel support, rear wheel support and handle member attached to the second rotatable member through a second angle of rotation from a folded position to an unfolded position of the foldable stroller frame, wherein the first and second angles of rotation are not the same.

12. A folding mechanism usable with a foldable device, the folding mechanism comprising:

a first rotatable member and a second rotatable member rotatably mounted for rotation relative to each other, the first rotatable member having a first elongated aperture containing a first gear portion and the second rotatable member having a second elongated aperture containing a second gear portion, the first rotatable member and the second rotatable member having planar faces in face-to-face juxtaposition to provide laterally spaced parallel plates having the first and second elongated apertures, the first rotatable member positioned for rotation in a first plane of rotation and the second rotatable member positioned for rotation in a second plane of rotation spaced from the first plane of rotation;

a third gear in simultaneous driving engagement with the first and second gear portions such that the first and second rotatable members rotate relative to each other in geared coordination, wherein a first pitch diameter of the first gear is sized to rotate the first rotatable member through a first angle of rotation from a folded position to an unfolded position of the foldable device, and wherein a second pitch diameter of the second gear is sized to rotate the second rotatable member through a second angle of rotation from a folded position to an unfolded position of the foldable device, and the first and second angles of rotation are not the same; and is

The foldable device has first, second, and third frame members, the first rotatable member configured to be attached to a first one of the first, second, and third frame members, the second rotatable member configured to be attached to a second one of the first, second, and third frame members different from the first, and third and fourth gears configured to be supported by a different third one of the first, second, and third frame members.

13. The folding mechanism of claim 12 wherein the first and second rotatable members are positioned to rotate in parallel first and second planes of rotation.

14. The folding mechanism of claim 12 wherein said third gear includes a first pinion and a second pinion, said first and second pinions being in a coaxial arrangement.

15. The folding mechanism of claim 14 wherein the first pinion and the second pinion are a single piece.

16. The folding mechanism of claim 14 wherein the first and second pinions are two pieces configured to rotate as a unit.