Abstract:
A foldable trunk bike comprised of a front frame and a rear frame; the front frame containing handle, fork, and front wheel while the rear frame related to a trunk fixed with a retractable crossbar, stay fork, seat tube, rear wheel, drive chain and crank; a mobile pipe connecting the front frame of the bike penetrating into the fixed stand, the handle folded downward, and the entire bike retreated into the trunk to facilitate carriage and towing.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     (a) Technical Field of the Invention  
         [0002]     The present invention is related to a foldable trunk bike, and more particularly to one having the retracted rear frame of the bike in a trunk and the front frame of the bike together with crossbar and handle retreated into the trunk frame for easy carriage and towing.  
         [0003]     (b) Description of the Prior Art  
         [0004]     For providing advantages of easy portability, energy saving, life style, and healthy, the foldable bike becomes increasingly popular and helps ease problems of urban pollution and difficulty in finding a parking booth. Therefore, the fordable bike as a light transportation means will be a mainstream in the world.  
         [0005]     As illustrated in  FIG. 1  of the accompanying drawings, a foldable bike  1  of the prior art is comprised of a fork  11 , a seat stay  12  and a cross bar  13  that connects the fork  11  and the seat stay  12 . Wherein, a front wheel  111  is provided to where below the fork  11 ; and a handle  112 , above. A rear wheel  121  and a transmission  122  are provided to where below the seat stay  12 ; a seat tube  123 , above the transmission  122 ; and a seat  124  at the top of the seat tube  123 .  
         [0006]     When retracted, the bike has its handle  112  above the fork  11  folded downward by releasing a knob  114  adapted to a coupling  113 ; the knob  114  retightened again to hold the retracted handle  112  in place; another knob  131  adapted to the crossbar  13  released to fold in the fork  11  to where the seat stay  12  is located as illustrated in  FIG. 2 ; the knob  131  locked up; and finally the height of the seat tube  123  reduced to achieve the purpose reducing the size of the bike.  
         [0007]     However, the prior art is found with the following flaws: (1) Extra force is required resulting in painful finger(s) by the heavy crossbar  13 ; (2) The volume is reduced for the retracted bike, but it gets wider and looks a mess without a casing; and (3) It won&#39;t be easy to carrying the retracted bike for a longer way.  
       SUMMARY OF THE INVENTION  
       [0008]     The primary purpose of the present invention is to provide a foldable trunk bike that when folded in will not hurt the finger(s) of the rider. To achieve the purpose, the bike of the present invention is comprised of a front frame and a rear frame connected by a crossbar to retract or stretch both frames by operating a rotary stem adapted to the crossbar.  
         [0009]     Another purpose of the present invention is to provide a foldable trunk bike that permits volume reduction when retreated. To achieve the purpose, a trunk is fixed to its rear frame to accommodate the front frame when retracted.  
         [0010]     Yet another purpose of the present invention is to provide a foldable trunk bike that it is easy to carry along as with a luggage trolley. To achieve the purpose, a caster is each provided on both sides of the tail of the trunk and the handle becomes the frame of a luggage trolley.  
         [0011]     Yet another purpose of the present invention is to provide a foldable trunk bike that when retracted will not become wider to facilitate carrying the trunk.  
         [0012]     The foregoing object and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.  
         [0013]     Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is a schematic view of a foldable bike of the prior art.  
         [0015]      FIG. 2  is a schematic view showing the foldable bike of the prior art is retracted.  
         [0016]      FIG. 3  is a schematic view of a preferred embodiment of the present invention.  
         [0017]      FIG. 4  is a sectional view of the preferred embodiment of the present invention.  
         [0018]      FIG. 5  is a schematic view showing a construction of a crossbar of the preferred embodiment of the present invention.  
         [0019]      FIG. 6  is a schematic view showing the crossbar as assembled.  
         [0020]      FIG. 7  is an exploded view showing a construction of a crank of the preferred embodiment of the present invention.  
         [0021]      FIG. 8  is a schematic view showing the crank as assembled.  
         [0022]      FIG. 9  is a schematic view showing adjustment of the crank.  
         [0023]      FIG. 10  is a schematic view showing that the preferred embodiment of the present invention is retracted.  
         [0024]      FIG. 11  is a side view of the preferred embodiment of the present invention as retracted.  
         [0025]      FIG. 12  is a schematic view showing the towing of the preferred embodiment of the present when retracted.  
         [0026]      FIG. 13  is another schematic view showing that the preferred embodiment of the present invention is retracted.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0027]     The following descriptions are of exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims.  
         [0028]     Referring to  FIG. 3  for a preferred embodiment of the present invention, a foldable trunk bike  2  is essentially comprised of a front frame and a rear frame. Wherein, the front frame includes a fork  21 , a handle  22 , and a front wheel  23  as illustrated in  FIG. 4  while the rear frame has a crossbar  4  fixed to the inner side of a trunk  3 , and the crossbar  4  is integrated with a seat stay  24 , a seat tube holder  25 , and a rear wheel. A crank  6  penetrates both sides of the trunk  3  and connects to an axle of a drive chain  27 ; and the trunk  3  is fixed to the crossbar  4  with multiple screws  35 .  
         [0029]     The front wheel  23  is fixed to where below the fork  21 , and the handle  22  is connected to a head tube  21  extending from the fork  2 . By releasing a knob  213  adapted to the coupling  212 , the handle  22  is folded downward to rest on the fork  21  as illustrated in  FIG. 11 ; and the knob  213  is retightened again for the handle  22  to be secured on one side of the fork  21 . It is to be noted that the front frame of the present invention falling within the scope of the teaching by the prior art.  
         [0030]     A crossbar  4  is fixed in the trunk  3  in a size merely sufficient to accommodate both of the front and the rear frames when folded in as illustrated in  FIG. 4 . A front cover  31  is provided to the trunk  3 . Two holes  311 ,  312  are respectively provided in the upper part and the front of the front cover  31  to permit penetration by a seat tube  281  and the head tube  211  of the fork  21 . The rear end of the crossbar  4  is connected to the seat stay  24 , and the rear wheel  26  is fixed to the tail of the seat stay  24 . The seat tube holder  25  is fixed at the middle of a fixed stand  41  of the crossbar  4  for the placement of the seat tube  281  provided at its top a seat  28 .  
         [0031]     Now referring to  FIG. 5 , the crossbar  4  is comprised of a fixed stand  41  and a mobile stand  42 . Wherein, a seat tube holder  25  is vertically provided to the fixed stand  41  at where between two tubes  411  arranged in parallel. A gap is provided at the lower edge of a front end  412  of each tube  411 , and four flaps  413  are fixed to the external wall of both tubes  411  at where in relation to the inner edge of the gap for the insertion of a rotary stem  5 . The rotary stem  5  includes a rotary lever  51 , an axle  51 , and two tube gears  53 . The rotary lever  51  is pivoted to the axle  52  for respectively placing both gears  53  at where between those four flaps  413  of both tubes  411 . A tip  521  fixed to the axle  52  is engaged into the tip of the axial hole provided on each gear  53  so that both gears  53  on the axle  52  turn synchronously when the rotary lever  51  is turned.  
         [0032]     The mobile stand  42  of the crossbar  4  is comprised of two tubes  421  in parallel with each other. A fork sleeve  423  is fixed to the front of both tubes  421  of the mobile stand to secure the penetration of the head tube  211  of the fork  21 . Meanwhile, a rack  422  is fixed to the bottom of each tube  421  to permit the tube  421  to penetrate into the tube  411  of the fixed stand  41  as illustrated in  FIG. 6 . Accordingly, the rack  422  at the bottom of each tube  421  of the mobile stand  42  is merely engaged with the gear  53  of the rotary stem  5 . When the rotary stem  5  clockwise or counter-clockwise, the mobile stand  42  retreats into or extends from the fixed stand  41 . To make sure that the mobile stand is firmly secured, a ring clip  43  is disposed to the end  412  of each tube  411  of the fixed stand  41  at where the gap is provided when the crossbar  4  is adjusted to stay in position as illustrated in  FIGS. 5 , and  6 .  
         [0033]     Whereas the crank  6  of the bike penetrates outside the trunk  3  to be engaged to the axle of the drive chain  27 , the crank  6  and a pair of pedals attached to it must be able to turn and rest on the external wall of the trunk  3  for achieving the purpose of reduced volume. Therefore, the crank  6  has a crank rod  61  to penetrate through a crank holder  62  as illustrated in  FIG. 7  and is then locked up at the end of the crank holder  62  with an adjustment nut  63  before screwing the pedal  64  to the crank rod  61 . Wherein, the crank rod  61  is provided with a head in larger diameter as illustrated in  FIG. 8 , and two protruding bits  612  are provided 180° apart from each other to the lower edge of the head  611 . A screw hole  613  is provided at the lower end of the crank rod  61  for the pedal  64  to screw in. Two pairs of abutted fillisters  622 ,  623  arranged at right angle to one another are provided on the top end surface of the tube disposed with a central hole  621  for the crank holder  62 , and an axial branch  624  extends from one side of the crank holder  62  to be screwed the axial of the drive chain  27 . A thread  625  is provided on the tube below the crank holder  62  and multiple gaps  627  at a given spacing are provided to the lower edge  626  of the crank holder  62  with the lower edge in a slightly diminished diameter. The nut  63  is screwed to the lower edge  626  of the crank holder  62  and is provided a thread  631  on the inner wall and a female thread  632  is provided on the outer wall. A lower end  633  of the nut  63  is tapered to facilitate rotating by the rider of the bike.  
         [0034]     To ride the bike, the crank rod  61  has those protruding bits  612  under the nut inserted to those fillisters  622  provided in parallel with the axial branch  624  and tightened with the nut from the end of the crank holder  62 . The crank rod  61  is fastened in position by having the lower end  633  of the nut  63  to fasten the lower edge  626  of the crank holder  62 . Accordingly, both pedals  64  are adjusted to a position at right angle to the trunk  3  for the rider to step on them. To fold in the bike, the nut  63  is released; the crank rod  61  is turned for 90° to cause both protruding bits  612  below the nut  63  to be inserted to respective fillisters  623  vertically disposed to the branch  624  as illustrated in  FIG. 9 ; and finally the nut  63  is tightened up to have both of the crank rod  611  and the pair of the pedals  64  to rest on their respective fillisters  34  provided on the surface of the trunk  3  as illustrated in  FIG. 10  to reduce the volume of the crank rod  611  and the pair of the pedals  64  protruding from the trunk  3 .  
         [0035]     Now referring to  FIG. 3 , the biker sits on the seat  28  and steps onto both pedals  64  with both feet striding over both sides of the trunk  3 . Whereas the trunk  3  covers up the rear frame to expand the volume of the bike to make the appearance of the bike is more attractive and avoid any awkwardness the rider may have by riding a small bike.  
         [0036]     At times, the biker may drive his car to a certain destination to enjoy the fun of riding a bike, and the bike is folded in and placed in the trunk of the car. To store the bike, first the front cover  31  is lifted up as illustrated in  FIG. 11 ; the handle  22  is turned for 180° to fold in both of the fork  21  and the front wheel  23  to where within the range of the crossbar  4 ; and the handle  22  is then folded downward and fastened with the knob  213  for the rider to poke his fingers into the trunk to release the clamps  43  on the mobile stand to turn the rotary stem  51  for both gears  53  to drive the rack  422  at the bottom of the mobile stand  41  as illustrated in  FIG. 6 . Both tubes  411  of the mobile stand  41 , and the fork, the handle and the front wheel fixed to the mobile stand  41  are retreated into the trunk  3 . The front cover  31  of the trunk  3  is let down and the rotary lever  51  is turned to rest in the fillisters  34  on the outer wall of the trunk  3  to diminish the volume of the protruding rotary lever  51 . Finally, the seat tube  281  is treated to leave only the seat exposing out of the upper edge of the trunk  3  to complete the retraction of the bike without the risk of getting finger(s) hurt and the retracted bike looks like a suitcase.  
         [0037]     Whereas one end of the handle sticks out of the trunk  3  for a small section, the biker could grab it to carry the bike. To facilitate towing, a caster  32  is each fixed to both sides at the lower edge in the tail of the trunk  3  as illustrated in  FIG. 12 . In case of stairs or any other place that prevents the towing, the biker simply carries the retracted bike by a handle  33  provided on the top of the trunk  3 .  
         [0038]     Furthermore, as illustrated in  FIG. 13 , only the fork, the handle and the front wheel are folded into the trunk  3  will significantly reduce the volume of the bike to spare three times of parking space, an advantage particularly welcome by any office building with very limited area for parking.  
         [0039]     It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.  
         [0040]     While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.