Related Applications

[001 ] The present invention claims the benefit of priority from Hong Kong Short-term Patent Application No. 16109224.1 filed on October 12, 2016, and Application No. 17103074.4 filed on March 24, 2017, the disclosure of which is incorporated herein in its entirety by reference.

Technical Field

[002] The present invention relates to a moving mechanism, and more particularly, to a hybrid wheeled and tracked moving mechanism having a balance system and moving on an even road with two wheels and controlling its moving direction in response to adjustment of rider's body balance, such that it is able to readily slide on the even road and small in size and very flexible in motion. When encountering rugged roads, obstacles, or stairs, the moving mechanism incorporates and uses jointly the wheels with tracks such that it can run readily on rugged mountain roads, move across obstacles on ordinary roads, and continuously climb over stairs of various slopes, ramps, and steps in a safe manner.

Background Art

[003] Most of the mechanical combination moving mechanisms are mainly provided for human use, and some of them are provided for people with disabilities, so the comfortability of moving mechanism is the primary concern. And secondly, as those disabled people have physical defects, they expect or are more eager to live as normal people. For example, when they are moving on the streets, they do not want to occupy more space than normal people, so that most of the wheelchair designers now tend to reduce the size of the wheelchair to ease their inconvenience in life. Unfortunately, the smaller the size of the wheelchair, the lesser the functionality thereof. Particularly, when encountering rugged roads, obstacles, or stairs, their wheelchairs of reduced size cannot pass through, such that they need to seek help frequently from other normal people despite of their eagerness to live as normal people. As a result, those wheelchairs capable of climbing stairs and crossing over obstacles came into being. However, their dimensions need to be relatively large in order to safely cross over the obstacles and climb over the stairs. Moreover, people with disabilities also have a desire, namely to use their hands to do other things while moving, like normal people do. A desired moving mechanism which could meet concurrently foregoing requirements, namely being high in comfortability, small in size, capable of safely crossing over the obstacles and climbing the stairs, and operable without using hands, is absolutely not available in the world. Inventions or products being slightly closer to the desired moving mechanism are listed as follows: [004] 1 . China Invention Patent No. 201510555652.6 has disclosed a tracked moving mechanism (see Fig. 1 a), which adopts a "water droplet type track design" featuring a combination of large and small wheels, and can climb over stairs of various slopes, move readily on even road surfaces, and cross over safely the rugged roads and obstacles. Since it has too many functions, its seat needs to be raised and lowered repeatedly, and its forearm must be extended or retracted frequently, and such a complex structure must be controlled by the rider with both hands and is relatively large in dimensions and difficult to control. One should also note that it is devised to use a caster as the front wheel for moving on even roads, but the rear wheel is definitely still a track, and no matter how the configuration or the shape of the track might change, its comfortability is no match for a tire. The conclusion is that it is relatively poor in comfortability and not small enough in dimension, and it also requires the rider to control the direction by hand.

[005] 2. Hong Kong Patent Application No. 16109224.1 has disclosed a tracked moving mechanism (see Fig. 1 b), which utilizes a "lightning type track design" capable of climbing stairs of various slopes and moving flexibly on smooth road surfaces. Owing to its unique lightning configuration, its forearm could be pressed against firmly the step surface to enhance greatly the safety while climbing the stairs. However, its comfortability is undesirable when moving on even roads as the front wheel and the rear wheel are definitely still tracks. The conclusion is that it is relatively poor in comfortability and not small enough in dimension, and it also requires the rider to control the direction by hand.

[006] 3. There is a wheelchair in the market, which moves on the even road with four wheels (as in Figure 1 c), and the wheels will be retracted and the tracks will be utilized when climbing the stairs (as in Figure 1 d). The advantage is that it is relatively flexible and comfortable when moving on the even road, and it could also realize a stair climbing function. Since it performs alternate operatons of wheels and tracks, it must use two different sets of drive motors, that is, a total of four motors, which increase the cost and complexity of the product. Further, it employs a pair of straight and flat tracks for climbing the stairs, such that the tracks can only act on the corner of the steps, whereby the wheelchair is very unstable and dangerous. The conclusion is that it is bulky and unable to safely move across the obstacles and climb up the stairs, and it also requires the rider to control the direction by hand.

[007] 4. The University of Switzerland has disclosed an electric wheelchair prototype (see Figures 1 e and 1f), wherein two wheels are engaged with and moved on the even road, and the direction of the wheelchair is controlled via a somatosensory balance system. However, the prototype will adopt a full track system for acting on and climbing over the stairs (as in Figure 1 h), such that the track assembly must be of a certain length, which will occupy a considerable space, even the prototype is engaged in the even road mode in which the track assembly is retracted thereinto (as in Figure 1f). The prototype is similar to a conventional stair climbing equipment, wherein a long and straight track is arranged at both sides for stair climbing, and the track can only be "acted on the corners of steps" (as shown in circles of Figure 1 h), such that its safety is absolutely inadequate. One should also note that the big wheels are completely off the ground at the moment, but the wheels will be kept running and wasting energy because the wheels and the tracks are rotated and driven by the same set of drive motors even though the wheels will not assist in the stair climbing operation at that moment. In addition, when the product prototype arrives at the top step of the stairs, the support wheels (as shown in the circle of Figure 1j) must be released and lowered at the appropriate time. If the support wheels are released too early, they will be stuck between the steps; and a sudden fall of the wheelchair will be resulted if they are released too late, and it will pose a danger to the rider in either case. In order to enable the support wheels to be placed in the proper positions at the right time, the sensor and the control system must be cooperated in a perfectly matching manner to ensure a faultless operation. Unfortunately, the existing sensors are very susceptible to external interference and will easily make an error. If a zero error operation is desired, it might be realized at the expense of a considerable amount of resources and money, whereby increasing the product development time and the cost thereof.

Brief Summary of Invention

[008] In order to solve the shortcomings and problems of the prior art, the present invention provides a "hybrid wheeled and tracked moving mechanism", which might adopt a two-wheel balance mode when moving on an even road, wherein the direction of the moving mechanism is controlled by adjusting the center of gravity of the rider, such that both hands of the rider are free to do other things; when moving on a rugged road or stairs, the moving mechanism might utilize an extendable crawler / track, to form a hybrid wheeled and tracked configuration, wherein the bottom or lower part of the moving mechanism forms substantially a " _^ " shape, so as to climb over stairs of various slopes, and move across fields and obstacles in an ideal and safe manner. The moving mechanism mainly comprises or consists of three parts, including: a wheel balance running mechanism, an extendable track mechanism and a support bracket balance mechanism.

[009] According to a moving mechanism of the present invention, comprising a first wheeled unit and a second tracked unit operatively connected and moved / driven synchronously with each other; wherein the first wheeled unit is preferably arranged fixedly in position and acted as a drive unit and adapted for acting or moving on an even working surface; and the second tracked unit is preferably adapted to be movably connected and cooperated with and movable in position in relation to the first wheeled unit and acted as a driven unit for acting or moving on a varied working surface including a stairs of various slopes, a rugged road surface, and an all-terrain ground surface, wherein:

the moving mechanism is configured to be switchable between a wheel drive mode adapted for moving on the even working surface and a wheel-track combined drive mode adapted for moving on a varied working surface;

wherein, in the wheel drive mode, the moving mechanism is configured to be operated or controlled preferably via a somatosensory control system and the second tracked unit is configured to be arranged in parallel with or substantially parallel with the first wheeled unit in a length direction or a moving direction thereof; and

wherein, in the wheel-track combined drive mode, the moving mechanism is configured to be operated or controlled preferably via a manual control system and the second tracked unit is configured to be intersected with the first wheeled unit and preferably formed a contacting / acting lower portion or lower profile of a substantially " _^ " shape for making contact with the working surface, so as to adapt to and closely lean against different varied working surfaces or move freely over the varied working surfaces..

[0010] In some embodiments of the moving mechanism according to the present invention, the second tracked unit is convertibly and/or rotatably switchable between an inactive position and an active position; wherein in the active position the second tracked unit extends toward in direction of the working surface and preferably rotates downwardly about an axis until its front end leans against the working surface and forms jointly with the first wheeled unit the contacting / acting lower portion or lower profile of the substantially " _^ " shape, whereby rendering the moving mechanism to be switched from a wheel drive configuration to a wheel-track combined drive configuration; and in the inactive position the second tracked unit is retracted in direction away from the working surface and preferably rotates upwardly about the axis until it is separated from the working surface and in a position in parallel with and above the first wheeled unit, whereby rendering the moving mechanism to be switched from the wheel-track combined drive configuration to the wheel drive configuration.

[001 1 ] In some embodiments, the first wheeled unit and the second tracked unit are configured to be operatively connected and moved synchronously with each other via a gear graduation / adjustment / shifting assembly for making their speed/gear ratios equal and/or making their running speed be consistent with each other, and the gear shifting assembly comprises a bull gear arranged at the first wheeled unit and a pinion gear arranged at the second tracked unit and a connection or transmission member, and preferably a chain, arranged between them for enabling them to move synchronously; wherein a rotation radius ratio or an outer diameter ratio between the bull gear and the first wheeled unit is identical to that between the pinion gear and the second tracked unit.

[0012] In other embodiments, further comprising a seat or support unit for accommodating an operating unit and / or an operator of the moving mechanism; and a first balancing and driving unit adapted for the wheel drive mode and a second balancing and driving unit adapted for the wheel- track combined drive mode, which are operatively connected with the seat or support unit for detecting and controlling states of balance and motion of the moving mechanism and are preferably arranged separately and used alternately; wherein in the wheel drive mode the first balancing and driving unit is activated to maintain balance of the seat or support unit and determine moving direction corresponding to the balance state of the moving mechanism and keep the second balancing and driving unit deactivated; and in the wheel-track combined drive mode the second balancing and driving unit is activated to maintain balance of the seat or support unit and enable its bearing surface to be always substantially in parallel with horizontal plane and determine moving direction corresponding to the balance state of the moving mechanism and keep the first balancing and driving unit deactivated.

[0013] In some embodiments, a length of the second tracked unit is substantially equal to that of the seat or support unit so as to be substantially received entirely underneath the seat or support unit in the wheel drive mode. The length is shorter than the prior art 20% or above, so as to save space advantageously.

[0014] In some embodiments, the first wheeled unit comprises a hub motor, a wheel and a bull gear coaxially arranged at and driven by a spindle of the hub motor; and the second tracked unit comprises a substantially elongate track, and the track comprises a first driven wheel and a second driven wheel arranged at its opposite ends and a pinion gear coaxially arranged with the first driven wheel; wherein the bull gear and the pinion gear are in direct engagement or in transmission connection via a connection or transmission member, so as to move synchronously and drive the moving mechanism in the wheel-track combined drive mode; and the track comprises a retractable push rod movably connected thereto, and telescopic operations of the push rod allow the track to be moved back and forth correspondingly along a predetermined orbit relative to the first wheeled unit, so as to enable the second tracked unit to be convertibly switchable between an inactive position and an active position for performing predetermined operations; and/or to enable the moving mechanism to be switchable between the wheel drive mode and the wheel-track combined drive mode and to form the lower profile of the substantially " _^ " shape of the moving mechanism for performing predetermined operations.

[0015] In other embodiments, the lower profile forms a substantially triangular space, and a height of the triangular space is substantially 80% to 120% and preferably 90% of that of the second tracked unit, so as to accommodate and facilitate climb-over of raised portions of the working surface encountered during motion thereof, so as to reduce the possibility of sudden drop / fall of the moving mechanism.

[0016] In other embodiments, configurations of the second tracked unit and / or the first wheeled unit are configured to enable or facilitate at least one portion of any one of the units to be located on or supported by a plane surface of one substantially flat portion of the varied working surface or a plane surface of another nearby or adjacent substantially flat portion of the varied working surface when at least one portion of another one of the units is located on or supported by an inclined / uneven / angular portion or corner portion of the varying working surface.

[0017] In other embodiments, the second tracked unit and the first wheeled unit are configured to enable at least one portion / fulcrum constituting the lower portion or lower profile of the substantially 'W shape to be always lean against a step surface of a step providing a relatively large support force while moving on a stairs, such that the step surface is used as a primary supporting surface of the moving mechanism to prevent it from tipping when another portion / fulcrum is located on or supported by a step corner of another step providing a relatively small support force.

[0018] In other embodiments, the second tracked unit is configured to be intersected with the first wheeled unit in the length direction or the moving direction at an angle, and the angle is configured and adapted with respect to an estimated or measured range of slope of stairs, an estimated or prescribed ruggedness range of rugged road in a predetermined deployment area.

[0019] The advantage of the present invention lies in that, a wheel-track hybrid design is adopted for climbing over the stairs (as in Fig. 1g), and because the principle and mechanism of stair climbing do not depend entirely on the track assembly / unit, the length of the track assembly can be reduced, and the track assembly can be received and hidden between the bottom of the seat and the big wheel via a decent mechanism (Figure 1 g), so that the overall dimensions is further reduced. Secondly, since the present invention adopts the wheel-track hybrid design, which not only will not waste the energy in a manner as the prior art does, but also forms the lower portion of the shape of by which the moving mechanism could always be "acted on and supported by at least one step plane surface" when climbing over the stairs (as shown by star lines in Fig. 1 i), so it is absolutely safe in operation.

Brief Description of Drawings

[0020] The present invention will be described in details below with reference to the accompanying drawings, in which:

[0021 ] Figure 1 a is a side view of a tracked moving mechanism disclosed in Chinese Invention Patent No. 201510555652.6.

[0022] Figure 1 b is a side view of a tracked moving mechanism disclosed in Hong Kong Patent Application No. 16109224.1 .

[0023] Figure 1c is a schematic view of a prior art wheelchair on the market running on an even road with four wheels.

[0024] Figure 1 d is a schematic view of a prior art wheelchair on the market having its track engaged with corners of steps when climbing the stairs.

[0025] Figures 1 e-1 k are schematic views of comparison between technical solutions of the prior art and the embodiments of the present invention.

[0026] Figure 2a is a schematic view depicting the difference in diameter between the big wheel and the track when they are used jointly with each other. [0027] Figure 2b is a schematic view depicting the difference in diameter of the bull and pinion gears in the gear and chain assembly.

[0028] Figure 3a is a structural side view of the present invention depicting the three main mechanisms constituting the present invention.

[0029] Figure 3b is a structural top view of the present invention depicting the three main mechanisms constituting the present invention.

[0030] Figure 4a is a structural side view of the "wheel balance running mechanism" of the present invention illustrating the components constituting the same.

[0031 ] Figure 4b is a schematic structure diagram of the hub motor of the prior art employed by the present invention.

[0032] Figure 4c is a structural top view of the "wheel balance running mechanism" of the present invention illustrating the components constituting the same.

[0033] Figure 5a is a structural side view of the "extendable track mechanism" of the present invention illustrating the components constituting the same.

[0034] Figure 5b is a structural close side view of the gear and chain assembly.

[0035] Figure 5c is a structural top view of the "extendable track mechanism" of the present invention illustrating the components constituting the same.

[0036] Figure 6a is a structural side view of the "support bracket balance mechanism" of the present invention illustrating the components constituting the same.

[0037] Figure 6b is a structural top view of the "support bracket balance mechanism" of the present invention illustrating the components constituting the same.

[0038] Figure 7a is a schematic view of the present invention while running on an even road.

[0039] Figure 7b is a schematic view of the present invention while the center of gravity of the rider is tilted backward such that the wheel is rotated backwardly.

[0040] Figure 7c is a schematic view of the present invention while the center of gravity of the rider is tilted forward such that the wheel is rotated forwardly.

[0041 ] Figure 8a is a schematic view of the extendable track assembly of the present invention extended and reached the ground surface.

[0042] Figure 8b is a schematic view showing the state when the seat balance system is activated and the seat is raised and reached its maximum.

[0043] Figure 9a is a schematic view showing the state in which the rear wheel is acted on the step corner (as shown by circle) and the extendable track is supported on the step surface (as shown by star line) when the present invention is climbing the stairs. [0044] Figure 9b is a schematic view showing the state in which the rear wheel and the extendable track is stepped and supported on the step surface (as shown by star line) when the present invention is climbing the stairs.

[0045] Figure 9c is a schematic view showing the state in which the extendable track is acted on the step corner (as shown by circle) when the rear wheel of present invention is reaching the top step of the stairs or almost climbing down the first step.

[0046] Figure 9d is a schematic view showing the state in which the extendable track of the present invention is acted on the step corner (as shown by circle) when it is just reaching the top step of the stairs or just climbing down the first step.

Detailed Description of Invention

[0047] Some preferred embodiments of the present invention are set forth below in conjunction with the accompanying drawings, so as to illustrate in details the technical solutions of the present invention.

[0048] In the context herein, the "stairs" refers to stairs of the same or different slopes, the "rough road surface and all-terrain ground surface" refers to road surfaces having smooth or wavy, rugged surfaces, or terrains of various slopes.

[0049] The moving mechanism according to the present invention has the following features or advantages:

[0050] 1 . Hybrid wheeled and tracked design - the existing stair climbing mechanical equipment are mostly using tracked structure, or trying to use multiple relatively large wheels for stair climbing in an utmost manner. Those two mechanisms have respective advantages and disadvantages, and for example, the tracked one is good in terms of stair climbing capacity, but poor in comfort when running on the even road; the wheeled one is good in comfort when running on the even road but poor in terms of stair climbing capacity. The present invention is a novel combination of those two mechanisms by taking advantage of respective merits, namely to utilize the wheel when running on the even road to make it comfortable and flexible; and use them conjunctly when climbing over the stairs or rugged road, wherein the lower portion of them forms a configuration of a substantially shape, such that the moving mechanism can easily climb over the stairs of different slopes and can reach the top of the stairs in a stable manner (Figures 9a-9d).

[0051 ] 2. Self-balancing vehicle and tracked vehicle hybrid design - the electric self-balancing vehicle are very popular nowadays and can be found in the streets and everywhere around the world, which is advantageous in that it is not only light and flexible, but also allow the hands of the rider to be free to do other things. The drawback is that it will be beyond its capability when it comes to obstacles or stairs because it cannot climb over the same. The tracked moving mechanism capable of stair climbing has increasingly matured in technology in recent years, and there is no doubt on its climbing capacity and safety. However, it is always no match for a self-balancing vehicle in terms of their flexibility, freedom and comfort when running on the even road. The present invention is a novel combination of them by taking advantage of and combining respective merits of both, whereby surely benefiting those in need in the world.

[0052] 3. Gear and chain modular gear graduation / adjustment / shifting design - there has never been a moving mechanism utilizing hybrid wheeled and tracked mechanism, the main reason is that the running speed of them is different. As shown in Figure 2a, D1 > D2, the difference between the diameter of both makes their speed ratio to be D1 : D2. That is to say, the rotation speed of the big wheel will be faster than the tracked assembly, so the big wheel will always tend to push forward or pull backward the tracked assembly, so that the moving body is very unsmooth in motion. In the present invention, a set of "gear and chain modular gear graduation / adjustment / shifting assembly" is preferably introduced between the large wheel and the tracked assembly. As shown in Fig. 2b, d1 > d2, and if D1 : d1 = D2: d2, the speed ratio of them becomes the same, such that the speed of the big wheel and the tracked assembly are inconsistent with each other, whereby the moving mechanism can run in a smooth manner.

[0053] 4. The alternate employment of the somatosensory balance system and the automatic balance system of the support bracket - when running on the even road, the rider wants to have both hands available to do other things, so the rider will use body balance to control the direction of the moving mechanism. When stair climbing is needed, the rider must concentrate and should not be distracted by using hands to do other things. In this regard, the rider must not rely on body balance for controlling the direction of the moving mechanism when climbing the stairs. The present invention creates a system for alternate employment of the somatosensory balance system and the automatic balance system of the seat, wherein the somatosensory balance system is deactivated once the tracked assembly is extended to touch the ground, and then the automatic balancing system of the seat is activated at the same time. As shown in Figures 9a-9d, the seat will perform automatically self-adjustments in response to the slop of the stairs, whereby allowing the seat to be always balanced with respect to the ground, and increasing substantially the safety of stair climbing.

[0054] 5. Superior in both of even road running and stair climbing - as the present invention use jointly the wheel and the track in a wise manner, the relatively long or elongated tracked assembly is retracted and only use two wheels for sliding on the even road, such that the volume or dimensions of the moving mechanism is minimized, and it will occupy minimum road space and it is also very flexible and practical. When it encounters the stairs, the tracked assembly can be extended to the frontmost / far end, so that the fulcrum for stair climbing is extended or prolonged. In addition, the formation of the substantially 'W shape between the big wheel and the track assembly will enable the moving mechanism to be always "acted on and supported by each of respective steps" when climbing over the stairs (as shown by star lines in Figs. 9a-9b), whereby the moving mechanism could climb over stairs of various slopes in a very safe manner. [0055] 6. Freeing of both hands of the rider - those who need to use the technical solution of the present invention are mostly people with disabilities, elder people, or those with bad legs, and they absolutely deserve to act like the normal one to have both hands free to use smart phones, take pictures, and the like, while moving on the streets. The present invention provides a hybrid design of electric self-balancing vehicle and the track vehicle, which could realize their desire for many years, and its practicability is certainly the highest among the peers in the art.

[0056] Figures 3a and 3b show a perspective view of an embodiment of the " hybrid wheeled and tracked moving mechanism" of the present invention, which shows schematically only a portion of the components for the clarity thereof. The mechanism of the present invention comprises: a wheel balance running mechanism 1 , an extendable track mechanism 2, and a support bracket balance mechanism 3.

[0057] The wheel balance running mechanism 1 (see Figs. 4a to 4c) comprises a left hub motor and a right hub motor 1 10 (1 10 is a prior art product and thus it will not be described in details herein, and 1 10 may be another actuating mechanism, such as a geared motor, a fuel powered actuating device, and the like).

[0058] The outer periphery of the hub motor 1 10 is fixedly connected to a tyre / tire 1 1 1 (1 1 1 may be an inflatable rubber tire, a solid rubber tire or an enclosing element of other materials). The tire 1 1 1 serves to make direct contact with the ground, and should have the capabilities of making friction contact with the ground, engaging the step corner and providing damping effect.

[0059] The power of the hub motor 1 10 is directly outputted from the connection shaft / spindle 1 12 of the hub motor, and the spindle 1 12 is movably connected to the main frame of vehicle body 101 .

[0060] The driving energy source of the wheel balance running mechanism 1 is the existing energy source, which might be a battery, gasoline or solar energy source, etc., and the dimensions and size of different energy source might vary, so they might be mounted at different locations, and will not be described in details hereinunder.

[0061 ] The wheel balance running mechanism 1 might comprises a manual controller, which is also a prior art controller, and there are a variety of brands and models to choose, so it could be dispensed with and will not be described in details below.

[0062] The wheel balance running mechanism 1 comprises a somatosensory control system. Since the technology of electric self-balancing vehicle has matured, there are a variety of somatosensory control systems, which will not be described in further details below.

[0063] When the rider utilizes the somatosensory control system by tilting forwardly the center of gravity (see Fig. 7c), the gyro / gyroscope 31 1 will senses the deviation of the center of gravity of the rider, and then it will communicate with the hub motor 1 10 through the somatosensory control system to control the speed of forward rotation thereof (as in Figure 7c), if the center of gravity has been forwardly tilted continuously, the speed of forward rotation will be increasing. On the contrary, when the center of gravity of the rider is tilted backwardly (as shown in Fig. 7b), the somatosensory control system controls the speed of backward rotation of the hub motor 1 10 to produce the acceleration or pause effect. If the gyro 31 1 senses that the center of gravity of the rider is deflected to the right, it will communicate with the hub motor 1 10 through the somatosensory control system to increase the speed of the left wheel while slowing the speed of the right wheel or reversing the right wheel. On the contrary, if the somatosensory control system detects that the center of gravity of the rider is deflected to the left, and the system will drive and accelerate the right wheel while slowing or reversing the left wheel.

[0064] The extendable track mechanism 2 (see Figs. 5a to 5c) has a driving force for effecting extension, which is originated from the electric push rod / retractable push rod of extendable track

200 (which may be other actuating means, such as a geared motor or a hydraulic push rod, and the like).

[0065] Firstly, the electric push rod of extendable track 200 is movably connected with the connection member 241 , and the connection member 241 is fixedly connected to the main frame of vehicle body 101 , so that the force generated by the electric pusher of extendable track 200 is counteracted by the main frame of vehicle body 101 .

[0066] The rotation force of the extendable track 232 is originated from the hub motor 1 10. When the hub motor 1 10 rotates, the connection shaft 1 12 of the hub motor will transmit the power to the bull gear 201 fixedly connected to the connection shaft 1 12, and the rotation force of the bull gear

201 is transmitted to the pinion gear 202 by the chain 231 . The rotation force of the pinion gear 202 is transmitted to the driven wheel 203 fixedly connected therewith via the driven shaft 221 fixed thereto. The rotation force of the driven wheel 203 is transmitted to the driven wheel 204 at the frontmost / far end via the track 232. As shown in Figs. 2a and 2b, since the diameter ratio between the tire 1 1 1 and the bull gear 201 is D1 : d1 and the diameter ratio between the driven wheels 203 and 204 (together with the track 232) and the pinion gear 202 is D2: d2. Since D1 : d1 = D2: d2, the speed of the tire 1 1 1 and the track 232 becomes synchronized even though the diameter of the tire 1 1 1 and the driven wheels 203 and 204 are different, as the difference of the gear ratio is compensated for by the gear assembly.

[0067] In some embodiments, the bull gear directly engages with the pinion gear or they could be interconnected via other intermediate or connection members.

[0068] When the moving mechanism of the present invention needs to climb over obstruction or the stairs, the electric push rod 200 of the extendable track is extended forward and the connection shaft 223 connected to the 200 is pushed forward. Since the connection shaft 223 is movably connected to the connection member 214 and the 214 is also in close contact with the connection member 213, a pair of extendable tracked assemblies will simultaneously extend forward when the electric pusher 200 of the extendable track is extended forward. [0069] The pair of extendable tracked assemblies are movably connected to the connection members 21 1 and 212 of the gear assembly by the driven shaft 221 , and the connection members 21 1 and 212 are also closely interconnected and are movably connected to the connection shaft 1 12 of the hub motor. Owing to this closely connected structure, such that the pair of extendable tracked assemblies will not deviate from the desired orbit when extending forward and retracting backward, whereby the tracked assemblies can stay in the desired locations.

[0070] The support bracket balance mechanism 3 (see Figures 6a to 6b) comprises a balance push rod for support bracket 300 (which may be other actuating means, such as a geared motor, a hydraulic push rod, or the like), a gyroscope 31 1 (31 1 is either two-dimensional or three- dimensional) and a support bracket / mechanism 310 (310 may be a seat or other means for accommodating cargo).

[0071 ] Firstly, the balance push rod for support bracket 300 is movably connected to the connection member 331 , and the connection member 331 is fixedly connected to the main frame of vehicle body 101 . Therefore, the power generated by the balance push rod for support bracket 300 is counteracted by the main frame of vehicle body 101 . The balance push rod for support bracket 300 is movably connected to the connection shaft 301 , and one end of the connection shaft 301 is movably connected to the chute 321 , and the chute 321 is fixedly connected to the main frame of vehicle body 101 . Thus, the chute 321 will limit the range of motion of the connection shaft 301 .

[0072] In addition, the other end of the connection shaft 301 movably connected to the balance push rod for support bracket 300 is movably connected to the connection member 322, and the 322 is movably connected to the connection member 333, and the 333 is fixedly connected to the support bracket 310, and the support bracket 310 is movably connected to the connection member 332, and the 332 is fixedly connected to the main frame of vehicle body 101 . Such a series of connections will fix the range of opening and closing operations of the support mechanism.

[0073] When the electric push rod 200 of the extendable track extends forward to the maximum extent, that is to say, the moving mechanism has been changed from "two wheel somatosensory mode" to "obstacle crossing and stair climbing mode". In this mode, the somatosensory balance system will be immediately deactivated and the "support bracket balance system" will be activated at once. That is to say, the rider cannot use their center of gravity to control the direction of moving mechanism, it should be switched to manual control.

[0074] The gyro / gyroscope 31 1 will send a message to the support bracket balance system when the moving mechanism is inclined during obstacle crossing and stair climbing, and the system will control and have the balance push rod for support bracket 300 extended or shortened with respect to the angle of inclination, and the balance push rod for support bracket 300 will transmit the power to the connection member 322 via the connection shaft 301 , such that the support mechanism 310 will be balanced with respect to the ground via the entire support bracket assembly. [0075] By means of the foregoing structures / configurations, the functions of the present invention are as follows (the support bracket 310 is set as a seat, so as to make the mechanism to be more specific):

[0076] 1 . Function for even road (see Figures 7a- 7c): In order to make the moving mechanism be more lightweight and compact, the electric push rod 200 of extendable track will be retracted to the minimum extent, so that the pair of extendable tracked assemblies are completely off the ground and retracted to the most inner position (see Figure 7a ). Thus, the rider can manipulate the direction of the moving mechanism (see Figures. 7b and 7c) by making use the somatosensory balance system and inclination of body in forward and backward and left and right direction, so that the hands of the rider are free to do other things as normal people do. As the moving mechanism is small in size, and the axis of the wheel is also located under the center of gravity of the rider's body, so that it can perfectly realize the function of in situ rotation in a flexible manner.

[0077] 2. Function for crossing over rugged road and obstacles (see Figure 8a): When it encounters the rugged mountain road or needs to cross over the obstacles, the electric push rod 200 of extendable track will be extended to the maximum extent, so that the frontmost end of the pair of extendable tracked assemblies make contact with the ground, so that the lower / bottom portion of the moving mechanism forms a substantially 'W shape (see Figure 8a). This model will also activate the support bracket balance system, so that the rider can maintain a vertical balance with the ground, whereby the moving mechanism can move freely on the rugged mountain road and also could easily cross over any obstacles encountered on the normal road.

[0078] 3. Function for stair climbing (see Figures 9a-9d): The greatest advantage of the present invention is that it is simple in operation and this function only needs to adopt the same mode for crossing over the rugged road and have the lower / bottom portion of the moving mechanism formed the "^" shape. As shown in Figures 9a and 9b, the advantage of forming the shape of "^" at the bottom portion is that the frontmost end of the extendable track will make contact with the step surface for effecting a strong supporting action (as shown by the star lines of Figures 9a and 9b) when climbing each of the steps of the stairs during the stair climbing operation of the moving mechanism. Even if the big wheel, as shown in Figure 9a, could only grabbed or acted on the "corner" (as shown by the circle of Figure 9a) and seems extremely unsafe, the extendable track can still play its role as being stepped on and supported by the step surface. The big wheel is also advantageous in that it has a relatively large contact surface, and as shown in Figure 9b, the big wheel will also play the role of " being stepped on the step surface" (as shown by the star lines of Figure 9b). In addition, when the moving mechanism reach the top of the stairs or climbing down the first step of the stairs, the substantially 'W shape formed at the bottom portion can also play its role. As shown in Figure 9c, even if the big wheel has reached the top of the stairs, the extendable track is still able to "acted on / engaged with / hooked on the step corner"; or as shown in Figure 9d, even when just climbing down the first step of the stairs, the extendable track is still able to "acted on / engaged with / hooked on the step corner", such that the moving mechanism do not come with the risk of sudden fall / drop as other tracked climbing equipment did. In this way, the present invention will produce a perfect stair climbing function by incorporating and combining these two very different driving mechanism having respective merits, namely the big wheel and the extendable track.

[0079] In summary, one of the features of the present invention is that the wheels are used in combination with the track. When running on an even road, the employment of wheels as the driving mechanism making direct contact with the ground is the most comfortable, most flexible and most acceptable solution. When crossing over the rugged road and the barrier and climbing over the stairs, the track is the best choice as it is the highest in comfortability, and it provides the best grasping action and the safest operation. But there has never been an invention or design capable of combining and jointly using them to form a multi-purpose moving mechanism with their respective merits. In addition, another feature of the present invention is a gear shifting assembly, wherein it is necessary to solve the problem of having different respective running speed in order to use jointly or conjunctly the wheel and the track. As the big wheels will run faster than the small wheels in the tracked assembly, so the moving mechanism will suffer from the inconsistent running speeds of them while running on the road. In order to solve this problem, the present invention has designed a set of gear shifting / adjusting assembly to have the speed of them adjusted to be consistent with each other. At the same time, it facilitates the positioning of the extendable tracked assembly during extending and retracting process thereof.

In addition, a further feature of the present invention is the system for alternate employment of the somatosensory balance system and the automatic balance system of the seat, wherein the somatosensory balance system allows the hands of the rider to be free to do other things, but it should be switched to the automatic balance system of the seat during stair climbing for the sake of safety thereof. The present invention will use them interchangeably and switch to an appropriate system at appropriate time, so as to make the entire mechanism more comfortable and safe.

[0080] Thus, a further feature of the present invention is to provide an improved electric balance vehicle having a stair climbing function. Although the existing electric balance vehicles have been very popular, but their market development are primarily for those healthy people. Even there are some electric balance wheelchairs for those with disabilities, such wheelchairs can be used only on the even roads and can provide limited help to them. The present invention combines two into one and introduces a safe and reliable stair climbing mechanism into a small and flexible electric balance vehicle, which can benefit the well-being of those in need.

[0081 ] While the advantages and preferred embodiments of the present invention have been described herein, it will be understood by those skilled in the art that the description herein is provided by way of example only and is not intended to limit the scope of the present invention. It is to be understood that, without departing from the scope of the present invention, the description details may be substituted by any other equivalent, or modifications or variations may be made based thereon.

list of relevant components and reference signs

wheel balance running mechanism 1

101 main frame of vehicle body

1 10 hub motor (connected with 1 1 1 )

1 1 1 tire or wheel (connected with 1 10)

1 12 connection shaft / spindle of hub motor (connected with 1 10) Extendable track mechanism 2

200 electric push rod / retractable push rod of extendable track (one end is movably connected with 241 , another end is movably connected with 223)

201 bull gear (fixedly connected with 1 12)

202 pinion gear (fixedly connected with 221 )

203 driven wheel (fixedly connected with 221 )

204 driven wheel (fixedly connected with 222)

21 1 connection member (movably connected with 1 12, 221 )

212 connection member (movably connected with 1 12, 221 )

213 connection member (movably connected with 221 , 222)

214 connection member (movably connected with 221 , 222)

221 driven shaft (fixedly connected with 202, 203, movably connected with 21 1 , 212, 213, 214)

222 driven shaft (fixedly connected with 204, movably connected with 213, 214)

223 connection shaft (movably connected with 200, 214)

231 chain (driving 201 , 202)

232 track (driving 203, 204)

241 connection member (fixedly connected with 101 , movably connected with 200) Support bracket balance mechanism 3

300 balance push rod for support bracket (movably connected with 301 , 331 )

301 connection shaft (movably connected with 321 , 322)

310 support bracket (fixedly connected with 31 1 , movably connected with 332, 333)

31 1 gyroscope (fixedly connected with 310)

321 chute (fixedly connected with 101 , movably connected with 301 )

322 connection member (movably connected with 301 , 333)

331 connection member (fixedly connected with 101 , movably connected with 300)

332 connection member (fixedly connected with 101 , movably connected with 310)

333 connection member (fixedly connected with 310, movably connected with 332)