The present invention relates to the field of bicycles. More particularly, the invention relates to a bicycle having a multi-functional frame.

Background of the Invention

Riding a bicycle is an entertaining pastime for children, providing them with a sense of independence while being able to exert energy in a positive manner. As bicycles are relatively costly, it would be desirable to provide a universal bicycle that is adjustable, to accommodate the size of many children, rather than having to purchase a new bicycle when a previously owned bicycle is found to be undersized.

Many height and reach adjustable bicycle frames are known from the prior art, including DE 3724426, DE 4232592, WO 2014/133579, and US 2014/0049022. Despite the adjustability of these prior art bicycle frames, the riding posture of many riders nevertheless is unnatural, leading to fatigue or even to injury if the rider is not sufficiently alert.

In order to improve riding posture, TWM 454969 and WO 2014/106311 disclose a bicycle frame structure by which the frame length and angle are able to be adjusted. However, as a frame section is angularly adjusted, the seat, which is connected with the frame section by a seat tube, is also angularly displaced. When the bicycle seat is set at an unnatural angle, the rider often suffers from discomfort, such as in the lower back, neck, knees or wrists, for example when the legs are unable to properly outstretched. A time consuming procedure for correcting the seat angle is needed in order to alleviate such discomfort.

Children continuously seek new adventurous activities. At times they choose to stand upright on the pedals while the bicycle they are riding advances, to benefit from the experience of a kick scooter at the speed of a bicycle. This activity is very dangerous, and it would be desirable to provide a bicycle that may be converted to a kick scooter.

It is an object of the present invention to provide a multi-functional bicycle frame that is sufficiently adjustable to accommodate the size of many different children.

It is an additional object of the present invention to provide a multi-functional bicycle frame that is configured to maintain a natural riding posture while the legs are able to be properly outstretched, in addition to being vertically and longitudinally adjustable.

It is an additional object of the present invention to provide a multi-functional bicycle frame that is convertible for use as a kick scooter. Other objects and advantages of the invention will become apparent as the description proceeds.

Summary of the Invention

The present invention provides a multi-functional bicycle frame, comprising a length adjustable cross bar that is pivotable about a rear wheel axle, wherein a crankset spindle is rotatably mounted on a mounting plate downwardly extending from said cross bar! a height adjustable sleeve connected to an end of a down tube which is fixedly connected to said cross bar, said sleeve being displaceable along a steerer tube of a bicycle fork; and a telescopingly extendable seat tube which is pivotably connected to an articulator unit mounted on top of said cross bar at one end thereof closest to a front wheel and which is angularly displaceable about a horizontal pivot axis of said articulator unit, wherein said cross bar and said seat tube are independently pivotable and are independently extendable and retractable to achieve a customizable frame geometry by which the distance between said rear wheel axle and crankset spindle is fixed, a seat connected to said seat tube remains at a substantially horizontal disposition and is spaced from said crankset spindle by a desired dimension, and a foot of a rider is able to be outstretched onto a corresponding pedal connected to said crankset spindle during a pedaling operation.

The present invention is also directed to a pedal unit, comprising a pedal spindle; a pedal body rotatable about said pedal spindle during a pedaling operation; a mounting member mountable on a crankset spindle! a tubular arm member which is formed with threading on its inner surface and which extends from said mounting member along an axis being substantially perpendicular to said crankset spindle! a tubular threaded extender connected to said pedal spindle and received within, and threadedly engageable to, said arm member, for adjusting, after being rotated when in threaded engagement with said arm member, the length of a pedaling related crank arm! and a securing element interactable with an opening formed in a tubular outer wall of said arm member for maintaining said extender at a desired protruding length with respect to a longitudinal end of said arm member.

The present invention is also directed to a method for converting a bicycle to a push scooter, comprising the steps of providing a frame comprising a rectangular cross bar that is pivotable about a rear wheel axle, wherein a crankset spindle is rotatably mounted on a mounting plate downwardly extending from said cross bar! a height adjustable sleeve connected to an end of a down tube which is fixedly connected to said cross bar, said sleeve being displaceable along a steerer tube of a fork mounted on a front wheel axle! and a pedal unit mounted on said crankset spindle! pivotably displacing said cross bar to a position at which its upper surface is substantially parallel to, and at a propelling facilitating distance from, an underlying ground surface, to allow a user to stand on top of said cross bar upper surface and apply a foot initiated driving force applied onto said ground surface during a propelling operation! setting said sleeve to a lowermost height with respect to said steerer tube; and setting said pedal unit to a straightened alignment such that a pedal spindle is substantially perpendicular to said crankset spindle.

Brief Description of the Drawings

In the drawings:

- Figs. 1A and IB are right and left views, respectively, of a bicycle according to one embodiment of the invention, shown in small-sized dimensions!

- Fig. 2 is a front view of the bicycle of Fig. 1A;

- Fig. 3 is a perspective view of the bicyc231e of Fig. 1A;

- Fig. 4 is a side view of the bicycle of Fig. 1A, shown in extended dimensions!

- Fig. 5 is a front view of the bicycle of Fig. 4!

- Fig. 6 is a top view of the bicycle of Fig. 4!

- Fig. 7 is a perspective view of two side brackets of an extendable cross bar!

- Fig. 8 is a side view of a sleeve when mounted on a steerer tube!

- Fig. 9 is a cross sectional view of the sleeve, cut along plane A-A of Fig. 8!

- Fig. 10 is an exploded perspective view of a reconfigurable pedal unit!

- Fig. 11 is an enlarged view of Detail A of Fig. 10!

^■ Fig. 12 is a perspective view of the pedal unit of Fig. 10, when retracted!

- Fig. 13 is a side view of the pedal unit of Fig. 10, when retracted!

- Fig. 14 is a perspective view of the pedal unit of Fig. 10, when extended!

- Fig. 15 is a side view of the pedal unit of Fig. 10, when extended! - Fig. 16 is a top view of the pedal unit of Fig. 10, when retracted and set to the pedaling facilitating alignment;

- Fig. 17 is a front view of the pedal unit of Fig. 10, when retracted and set to the pedaling facilitating alignment;

- Fig. 18 is a cross sectional view of the pedal unit of Fig. 10, when retracted and set to the pedaling facilitating alignment, cut along plane B-B of Fig. 17;

- Fig. 19 is a top view of the pedal unit of Fig. 10, when retracted and set to the straightened alignment;

- Fig. 20 is a front view of the pedal unit of Fig. 10, when retracted and set to the straightened alignment;

^■ Fig. 21 is a cross sectional view of the pedal unit of Fig. 10, when retracted and set to the straightened alignment, cut along plane C-C of Fig. 20!

- Fig. 22 is a side view of a push scooter, according to an embodiment of the invention, shown in small-sized dimensions!

- Fig. 23 is a perspective view of the push scooter of Fig. 22;

- Fig. 24 is a side view of the push scooter of Fig. 22, shown in extended dimensions! and

- Fig. 25 is a perspective view of the push scooter of Fig. 24.

Detailed Description of Preferred Embodiments

The present invention is a novel bicycle frame that comprises a length adjustable cross bar that is pivotable about the rear wheel axle, to customize the frame geometry, while the distance between the rear wheel axle and the crankset spindle remains fixed.

Figs. 1A-1B illustrate two different side views of bicycle 10, respectively, according to one embodiment of the present invention, shown in small-sized dimensions. Bicycle 10 comprises a U-shaped rear wheel mount 11, shown more clearly in Fig. 3, which is pivotably connected to axle 4 of rear wheel 8 by two spaced triangular mounting plates 16. An interconnecting element 13 extending between the two legs of mount 13 is also fixedly connected to telescopingly extendable cross bar 15, which extends towards the vicinity of front wheel 1. Cross bar 15 may be of conventional tubular construction, or alternatively may be rectangular. A rigid mounting plate 24 by which crankset spindle 14 is rotatably mounted extends downwardly from cross bar 15.

Front wheel 1 and rear wheel 8 are shown to be a small diameter for the benefit of child riders. It will be appreciated, however, that bicycle 10 is suitable for use with any other wheel size. Bicycle 10 may be equipped with a battery 12 for electrically driving front wheel 1 and rear wheel 8.

A telescopingly extendable seat tube 17 is pivotably connected to articulator unit 19 mounted on top of cross bar 15 at one end thereof closest to front wheel 1. Seat tube 17 is angularly displaceable about a horizontal pivot axis of articulator unit 19, and is securable at a selected angular position. A down tube 21 is fixedly connected at an angle to articulator unit 19. Sleeve 22 connected to the end of down tube 21 being remote from articulator unit 19 is displaceable along steerer tube 6 of bicycle fork 7, which is mounted on axle 3 of front wheel 1, and is height adjustable via one of a plurality of vertically spaced holes 9 formed in steerer tube 6. Stem 5 attached to handlebars 2 is received within, and rotatable with respect to, steerer tube 6 by a frictional fit, as well known to those skilled in the art.

As shown, handlebars 2 are set at a lowermost position with respect to steerer tube 6, and sleeve 22 is set to an intermediate height with respect to steerer tube 6 in response to the selected lowered position of cross bar 15. Cross bar 15 is fully retracted such that the distance between axles 3 and 4 is a minimum value. Seat 23 is shown to be above, and slightly to the rear from, crankset spindle 14, to allow a fully extended leg of a child rider to comfortably contact pedal 18.

Figs. 2 and 3 illustrate front and perspective views, respectively, of bicycle 10 shown in small- sized dimensions.

Fig. 4 illustrates a side view of bicycle 10, shown in extended dimensions. Cross bar 15 is extended such that the distance between axles 3 and 4 is increased. Additionally, cross bar 15 has been pivoted upwardly about rear axle 4 relative to the position shown in Fig. 1, following an arcuate path. To accommodate this pivotable displacement, sleeve 22 has been raised along steerer tube 6. Also, stem 5 and seat tube 17 have been extended. At times, the rider is not sitting in a comfortable position after having performed a frame extending operation, and has to rotate the extended seat tube 17 about the pivot axis of articulator unit 19 in order to achieve a comfortable sitting position such that outstretched legs are able to contact the pedal.

Bicycle 10 affords older children or any other experienced rider with many possibilities of customizing the riding conditions, such as the distance between seat 23 and handlebars 2 or the distance between seat 23 and crankset spindle 14. In addition, the pedaling stroke can be adjusted by selectively extending the length of pedal 18. For example, pedal 18 is fully extended when it is desired to perform a power stroke; however, when the rider desires to increase his riding speed, the stroke length may be reduced by retracting pedal 18.

Fig. 5 illustrates a side view of bicycle 10 shown in extended-sized dimensions. Fig. 6 is a top view of bicycle 10, showing a rearward fixed section 26 connected to rear wheel mount 11 and a forward extendable section 27 of the cross bar when extended. Mounting plate 24 (Fig. IB) extends downwardly from section 26.

Fig. 7 illustrates the two parallel side brackets 31 and 32 of the cross bar, between which articulator unit 19 is interposed. Side brackets 31 and 32 are formed with a plurality of longitudinally spaced apertures 34, such that the apertures of bracket 31 are aligned with those of bracket 32. The rearward fixed section of the cross bar is also formed with a plurality of longitudinally spaced apertures, and one or more of the apertures of the fixed section are alignable with the apertures of brackets 31 and 32, depending on the selected longitudinal dimension of the bicycle. The forward section is extendable to cover open regions between side brackets 31 and 32.

A side view of sleeve 22 when mounted on steerer tube 6 is illustrated in Fig. 8, and a cross sectional view thereof is illustrated in Fig. 9.

As sleeve 22 is fixedly connected to the cross bar, bearings 33 and 34 are mounted on steerer tube 6 within the interior of sleeve 22 to enable low friction contact during rotation of the steerer tube while being able to absorb thrust forces applied by the rider. Stem 5 is shown to be received within the interior of steerer tube 6 by a frictional fit.

A spring loaded stopper unit 37 having an annular wall 39 and two diametrically opposite pressing elements 41 with a terminal knob 42 radially passing through a corresponding spring housing 44 is positioned below sleeve 22 for defining the height of the latter. Pressing elements 41 are adapted to be quickly released and repositioned upon demand so as to be introduced into a selected hole 9 formed in steerer tube 6 and to thereby limit the downward movement of sleeve 22.

If so desired, a stopper unit 37 may be positioned above sleeve 22. Figs. 10-15 illustrate the extendable pedal unit 46. Pedal unit 46 comprises pedal 18, an annular mount 48 for being mounted on the crankset spindle within its central aperture 49, a tubular grooved arm 51 having an axis which is substantially perpendicular to the axis of mount 48, and tubular threaded extender 53 connected to pedal 18 for adjusting the length of the crank arm, when desired.

The external threading of extender 53 is threadedly engageable with corresponding threading formed in the inner face of arm 51. In order to prevent disengagement of extender 53 from arm 51 as a result of the applied forces during a pedaling operation, extender 53 is bored with a threaded hole 58 near the end thereof which is remote from pedal 18. A threaded fastener 59 is insertable within groove 54 formed in arm 51, which is substantially parallel to the axis thereof, in order to access and be engaged with hole 58.

Figs. 12-13 illustrates pedal unit 46 when extender 53 is retracted, and Figs. 14- 15 illustrates pedal unit 46 when extender 53 is extended.

The length of the crank arm, defined as the distance from the crankset spindle to the pedal spindle 67, is adjustable by rotating extender 53 in a desired direction, when extender 53 is threadedly engaged with arm 51 and pedal unit 46 is set to a straightened alignment, as will described hereinafter. Alternatively, extender 53 may be rotated when pedal unit 46 is set to the illustrated pedaling facilitating alignment. The crank arm length is adjusted in order to customize the length of the rider's legs or to accommodate a desired cycling method.

Referring now to Figs. 16-21, pedal unit 46 is reconfigurable from the pedaling facilitating alignment shown in Figs. 16-18 to the straightened alignment shown in Figs. 19-21, or vice versa.

As shown in Figs. 16 and 17, pedal 18 comprises spindle 67 having a hand manipulatable head 69 and lug 75 for pivotable attachment with extender 53, and a pedal body 62 with a central bore into which spindle 67 is receivable to allow pedal body 62 to rotate about spindle 67 during a pedaling operation. Pedal body 62 has an annular shoulder 68 for releasably engaging throat 57 of extender 53 when pedal unit 46 is set to the pedaling facilitating alignment.

As shown also in Figs. 18 and 19, throat 57 of extender 53 has an appendage 61 that is thinner than throat 57 and longitudinally extends therefrom to form an L- shaped throat. The bottom edge of appendage 61 has an oblique edge 63 remote from annular mount 48, resulting in a remote terminal end of reduced thickness.

Lug 75, which may terminate in a thin pointed end to avoid interference with extender 53 during rotation of pedal 18, overlies a portion of appendage 61, and is configured to receive within its aperture a pivot pin 77 that is received within a seat of appendage 61. Torsion spring 74 fitted about pivot pin 77 urges spindle 67 to the pedaling facilitating alignment. Lug 75 is also configured with an oblique edge 76 extending towards head 69, resulting in a head facing end of reduced thickness. When lug 75 and appendage 61 are coupled together, their combined collinear head facing edge 81 (Fig. 21) has a length that is less than the inner diameter of spacer disc 71, and the distance between oblique edges 63 and 76 of appendage 61 and lug 75, respectively, is greater than the inner diameter of spacer disc 71.

A compression spring 79 is mounted on a reduced thickness portion of spindle 67, and serves to bias shoulder 68 towards throat 57. Thus shoulder 68 is locked against throat 57 during a pedaling operation when spindle 67 is set to the pedaling facilitating alignment, yet pedal body 62 is free to rotate about spindle 67. In order to minimize friction during a pedaling operation, annular bearing 72 is fitted internally to shoulder 68 and spacer disk 71 is attached to bearing 72.

In order to reconfigure pedal unit 46 to the straightened alignment, pedal body 62 is pulled away from extender 53, after inserting fingers within the gap between throat 57 and pedal body 62, while counteracting the biasing force of compression spring 79 and separating shoulder 68 from throat 57. As shoulder 68 is separated from throat 57, spindle 67 is able to be rotated about pivot pin 77 until the axis of spindle 67 is aligned with the axis of extender 53, as shown in Fig. 21. When the force applied to head 69 is released, the biasing force of spring 79 forces pedal body 62 towards extender 53 until spacer disk 71 contacts oblique edges 63 and 76 of appendage 61 and lug 75, respectively, by a locking action and shoulder 68 surrounds head facing edge 81 of throat 57.

By virtue of the pivotably connected cross bar 15 and seat tube 17 and of the pedal unit that is configurable to a straightened alignment, the two wheeled vehicle described hereinabove may be advantageously converted to a kick scooter. As referred to herein, a "kick scooter" is a two wheeled vehicle that is propelled by a driving force applied by a foot of a standing rider onto the ground.

Figs. 22 and 23 illustrate side and perspective views, respectively, of kick scooter

80 shown in small-sized dimensions. As shown, cross bar 15 is pivotally displaced to a position at which its upper surface is substantially parallel to the underlying ground surface G, and sleeve 22 is set to a lowermost height with respect to steerer tube 6 in response to the selected position of cross bar 15. At this cross bar position, the feet of the user are stable and safe without risk of sliding off. Also, the feet of the user are in a propelling facilitating distance from ground surface G, such that the feet of the user can be easily lowered from cross bar 15 onto the ground surface and then be returned to the cross bar, for example in order to coast. Pedal unit 46 is set to the straightened alignment to prevent interference to the feet during a propelling operation, and also as an additional safety feature. In order to increase safety in use as a scooter, arm 51 is locked in its essentially horizontal position by a flat horizontal projection 79 which is mounted to the bicycle's frame by a perpendicular flat member 78. When arm 51 is folded, projection 79 penetrates the upper groove formed in pedal 18, such that arm 51 cannot rotate, until it is returned back to pedaling mode.

To accommodate young users, handlebars 2 are set at a lowermost position with respect to steerer tube 6. Also, cross bar 15 is fully retracted such that the distance between axles 3 and 4 is a minimum value. Seat tube 17 is fully pivoted towards steerer tube 6, by an angle of approximately 90 degrees from the position shown in Fig. 1, so that the user will be able to comfortably stand on top of cross bar 15.

Figs. 24 and 25 illustrate side and perspective views, respectively of scooter 80, shown in extended dimensions, such that stem 5 and cross bar 15 are fully extended.

While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried out with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without exceeding the scope of the claims.