Abstract:
A motorized retrofit kit for lightweight collapsible mini scooter is a complete conversion for a lightweight push scooter to a motor driven unit. Owners of existing scooters can install a mini electric motor battery system, wiring and on/off button with limited skills and equipment to drive the rear wheel of the scooter.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present invention claims the priority date of a prior filed provisional patent application having Ser. No. 60/240,548, and official filing date of Oct. 12, 2000, and which discloses substantial similar matter as described herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention is directed to a collapsible motorized mini scooter, a retrofit motorized unit in kit form for a mini scooter. 
     2. Description of the Related Art 
     During the past few years, the lightweight collapsible mini scooter has become very popular in the market place. The scooter is very durable and very compact when folded up. The steering tube can be collapsed, the handle grips folded and the unit can be placed in a bag and carried over one&#39;s shoulder. Children, teenagers and some adults use the mini scooter today. A motorized, unit for these existing scooters would be a great added value and enjoyment for existing scooter owners, as long as it comes in a kit form and is easy to install with minimum skills and equipment. 
     SUMMARY OF INVENTION 
     The invention is embodied in a kit form converting a non-motorized mini scooter into a motorized scooter which does not damage the original scooter construction by drilling, machining or breaking any of the original parts of the scooter. The kit will provide all the components to convert and motorize the mini scooter: motor, batteries, charging system and hardware for installation. 
     Power to the motor will begin when the rider engages a switch, which sends current to a relay, which in turn sends current to the motor, the motor thereby driving a rear wheel causing forward motion of the scooter. When the rider releases the switch, the current is discontinued. The drive is engaged by a positive lock lever or thumbscrew mounted with the motor bracket. A NiCad battery pack and the required relay are in a cavity located underneath a footrest platform. The motor bracket is placed where an existing fender is located by replacing the fender with the bracket and the motor. In turn, the fender is then placed on the motor bracket. The motor is activated by a button switch mounted on the scooter handle bar and ground current to the relay is sent through a rotating contact shoe on an adjustable handle bar tube, or an optional remote system a transmitter on the handle grips and an additional receiver located in the battery cavity. A cam lock motor bracket adjuster is used as well as a foot lock motor adjuster. The forward motion is obtained by a small spindle located on the electric motor shaft, which comes in contact with the rear wheel. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a razor type mini scooter. 
     FIG. 2 is a side view of the scooter shown in FIG. 1 with the retrofit kit according to the present invention installed. 
     FIG. 3 is a perspective view of the retrofit kit contents, including battery tray, isolator ring, contact shoe, and motor bracket thumbscrew. 
     FIG. 4 is a perspective view of the collar shown in FIG.  3 . 
     FIG. 5 is a perspective view of the motor bracket with thumbscrew shown in FIG.  3 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described the presently preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the invention and it is not intended to limit the invention to the specific embodiments illustrated. 
     The invention is embodied in a kit for converting a non-motorized scooter into a motorized scooter which does not damage the original scooter&#39;s construction by drilling, machining or breaking any of the scooter&#39;s original parts. Referring to FIG. 1, a non-motorized scooter  1  for use with the kit  51  (FIG. 3) of the present invention includes a base platform  3  which is stepped upon by the rider when the scooter  1  is in use. The scooter  1  also includes a head tube  15 , which attaches to the front of the base platform  3  by a hinge assembly  21 . The hinge assembly  21  permits the head tube  15  to rotate approximately 90 degrees from a reclined position for storage, to an extended position for use. The hinge assembly  21  preferably includes a hinge lock  23  for locking the head tube  15  in either a reclined or extended position. Telescoping through the head tube  15  is a steering column  7  including an upper tube  9  and a lower tube  11 . The steering column  7  is rotatably attached to the head tube  15  using bearings  17 , which are mounted to the top and bottom interior of the head tube  15 . Preferably, the upper tube  9  is slidably telescopic within lower tube  11  and can be locked in various vertical positions using a clamp lock  19 . At the top of the steering column  7  are horizontally extending handlebars  5  which enable the rider to rotate the steering column  7  by manual rotation of the handlebars  5 . Affixed at the bottom of the steering column  7  is a front fork  25 . Rotatably mounted by a front axle  29  to the front fork  25  is a front wheel  27 . 
     At the rear of the scooter  1  is a rear fork  31 , which extends rearwardly from the rear of the base platform  3 . The rear fork  31  is applied to a laterally extending rear axle  35 , which rotatably mounts the scooter&#39;s rear wheel  33 . Preferably, the scooter  1  also includes a rear fender foot brake  37 . The fender foot brake  37  is hingedly attached to the front of the rear fork  31  by a pin, or a screw and nut combination, which extends laterally through two holes  41  formed in the rear fork  31  and two corresponding holes formed at the front of the fender foot brake  37 . The fender foot break  37  is biased upwardly by a spring (not shown). In use, a rider of the scooter  1  depresses the fender foot brake  37  against the rear wheel  33  to inhibit the wheel&#39;s rotation and cause braking of the scooter  1 . 
     The scooter  1  of the prior art provides a lightweight collapsible structure, which is driven by a user by a push-and-go method in which a rider uses one of his feet to propel the scooter which is ridden by balancing on the rider&#39;s other foot. Referring to all of the FIGS. 2-5, and particularly FIG. 3, the kit  51  of the present invention is directed to converting the non-motorized scooter of the prior art into a motorized structure  50 . The kit  51  includes a bracket  53  (best shown in FIG. 5, a motor  59  and an additional fender foot brake  63  already affixed to the bracket  53 . Referring to FIG. 5, to this end, the bracket  53  includes a pair of top holes  57  for hingedly affixing the fender foot brake  63  using a pivot pin passing through the top holes  57  and corresponding holes formed at the front extremity of the fender foot brake  63 . Meanwhile, the motor  59  is affixed to the bracket  53  using typical fasteners at motor mount holes  60 . A larger aperture  62  is formed in the bracket  53  through which a spindle  61  of the motor  59  extends. 
     In a preferred embodiment, the kit  51  for converting the scooter  1  into a motorized scooter  50  includes a low torque motor having a twenty-seven winding, single strand armature. For a preferred embodiment for creating a high performance scooter, the motor  59  includes a fourteen winding, three strand armature. The motor  59  also preferably includes internal bearings for withstanding forces imparted upon the motor&#39;s spindle  61 . Suitable motors are available from Mabuchi Motor in Japan. 
     The kit  51  of the present invention also includes a battery pack  71  including a plurality of batteries  75  for providing electrical power to the motor. In a first preferred construction, the battery pack  71  includes twelve 1.2 volt rechargeable batteries. The batteries are wired to provide two sets of six 1.2 volt batteries wired in series, with each set of six batteries wired parallel to provide a battery pack  71  providing 7.2 volts. In a second preferred embodiment, the battery pack  71  includes fourteen 1.2 volt rechargeable batteries for providing additional torque. The batteries are wired to provide two sets of seven 1.2 volt batteries wired in series, with each set of seven batteries wired in parallel to provide a battery pack providing 8.4 volts. Providing protection for the battery pack  71  is a battery tray  73  which is affixed to the scooter  1  using Velcro attachment  77  or the like. 
     The battery pack  71  is connected to the motor  59  using relative high current wires  84  which extend from both the battery pack  71  and motor  59  and are connected using male and female connectors  79  and  81 . The flow of current from the battery pack  71  to the motor  59  is controlled using a control circuit  85  which includes a high current relay  83  controlled by a switch constructed as an on/off button  99 . Numerous suitable relays are available to those skilled in the art. However, a twelve-volt relay typically used to control the headlamps of automobiles has been found to be particularly acceptable. The on/off button  99  is connected to the relay  83  through a pair of signal wires  87  and  89 , which are, in-turn, connected by a contact strip  91  and a contact bar  95  in contact with the contact strip  91  by a circular collar  105 . 
     The kit  51  of the present invention preferably includes numerous minor attachments means for attaching the signal wires  87  and  89  to the scooter  1  such as cable ties  103  or mounting bases  101  having an adhesive backing. The above-described kit  51  provides all of the components necessary for transforming a typical prior art non-motorized scooter  1  into a motorized scooter  50 , which can be installed in only a few minutes using only a hammer and a screwdriver, the assembly of which will not damage the original scooter in any way. 
     Again with reference to all of the figures, to convert the non-motorized scooter  1  into a motorized construction  50 , the original fender foot brake is removed by removing the preexisting pivot pin  43 . In place of the preexisting fender foot brake, the bracket  53  is affixed to the scooter&#39;s rear fork  31  using pivot pin  43  which is threaded through the holes in the rear fork  31  and the bottom holes  55  formed in the bracket  53 . With reference to FIGS. 2 and 4, the bracket  53  is hingedly attached to the scooter&#39;s rear fork  31  with the pin  43  so that clockwise rotation of the thumb screw  67  against the base platform  3  causes the bracket,  53  to rotate rearwardly, which in-turn causes the motor&#39;s spindle  61  to engage the external surface of the scooter&#39;s rear wheel  33 . Thus, activation of the motor  59  causes the rear wheel  33  to rotate. Conversely, counter-clockwise rotation of the thumbscrew  67  causes the force of the motor spindle  61  against the surface of the rear wheel  33  to be reduced enabling the rider of the scooter  50  to operate the scooter in a non-motorized mode. In an additional embodiment, instead of using a thumbscrew  67 , a spring is used to bias the bracket  53  and motor  59  rearwardly against the scooter&#39;s rear wheel  33 . 
     With reference to FIG. 2, the battery pack  71  and relay  83  are mounted within a channel typically formed on the underside of the scooter&#39;s base platform  3 . After the battery pack  71  and relay  83  are mounted to the scooter&#39;s underside using typical fasteners known to those skilled in the art such as glue or Velcro, the battery cover  73  is also attached to the underside of the scooter&#39;s base platform  3  using Velcro or the like to protect the battery pack  71  and relay  83  from damage during riding. As shown in FIG. 3, the battery pack  71  is connected to the relay  83  and in-turn to the motor  59  through high current wires  84  and connectors  79  and  81 . 
     The control circuit  85  is installed on the scooter  50  by routing signal wire  87  through battery cover  73  to the front of the scooter&#39;s base platform  3  and then upwardly along the side of the scooter&#39;s head tube  15 . Preferably, the wire  87  is affixed in place using adhesive backed tie bases  101  and cable ties  103 . The contact strip  91  is affixed in annular fashion to the top of the head tube  15  using double stick tape or the like to form an electrical ring on the head tube&#39;s upper exterior surface. Meanwhile, the collar  105  is affixed to the lower extremity of the rotable steering column  7  so that the lower portion of the collar extends concentrically around the contact strip  91 . Attached to the interior of the collar  105  is the contact bar  95  which is positioned to slidably contact the side of the contact strip  91  as the steering column  7  and collar  105  are rotated. The single wire  89  extending from the contact bar  95  is routed upwardly along the length of the steering column  7 , and preferably is coiled along the steering column&#39;s upper tube  9  so that the upper tube  9  may still telescopically extend and retract within the steering column&#39;s lower tube  11 . The on/off button  99  is then affixed to the handlebars  5  using a bracket or tie wraps as could be constructed by those skilled in the art. 
     The on/off button  99  is preferably constructed so that depression of the button causes a current to flow through the switch, with the removal of pressure from the on/off button  99  causing the circuit to open. As would be understood by those skilled in the art, the signal wires  89  and  87 , in cooperation with contact strip  91 , in rotational contact with contact bar  95  provide a first electrical path to the on/off button  99  from the relay  83 . Providing a second electrical path from the on/off button  99  to the relay  83  is the frame of the scooter  50  itself. To this end, the handlebars  5 , steering column  7 , bearings  17 , head tube  15 , hinge assembly  21  and base platform  3  are all constructed of electrically conductive metal such as stainless steel. One of the terminals of the on/off button  99  is electrically connected directly to the underside of the platform base  3 . Thus, depression of on/off button  99  causes a circuit to close through signal wire  89 , contact strip  91 , contact bar  95 , signal wire  87 , handlebars  5 , steering column  7 , bearings  17 , head tube  15 , hinge assembly  21  and base platform  3  causing the relay  83  to close, permitting current to flow from battery pack  71  to the motor  59 . 
     Once the components of the kit  51  have been installed on the scooter  1 , a motorized scooter  50  is thus provided. Depressing the on/off button  99  energizes the motor  59  causing the rear wheel  33  to rotate. Braking is provided by depressing the fender foot brake  63  against the rear wheel  33 . 
     The preferred embodiment is the complete kit  51  (FIG. 3) ready for consumer purchase which includes battery charger  150 , twelve volt adapter  151 , spring installer  152 , pin installer  153  and all necessary wiring and relay installations. 
     Although the present invention has described with reference to the preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.