Abstract:
A slot car racing toy features toy cars that engage a slot formed on a track and through which slot they pick up electrical power. The electrical power supplied to the slot is generated by a manually-driven electrical generating means which also supplies the power to a sound effects unit.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates to toy racing cars, and in particular relates to a manually-driven speed controller of a slot car.  
         BACKGROUND OF THE INVENTION  
         [0002]    Toy slot cars, as shown in FIG. 1, are popular toys which usually consist of a track  01  and one or more cars  02 . The track  01  is a closed route that is formed by a number of connected track elements. Slots  011  are formed in each track element so that when the elements are connected the track  01  is provided with at least one continuous slot along which a car  02  may run. As is well known on both inner and outer sides of each slot there are provided electrically conducting strips  012  for supplying electrical power to the car. As shown in FIG. 2, a guiding axle  021  is provided at the bottom of a car  02  for guiding the car along the track and conducting friction elements  022  (such as a conducting brush) are installed on both sides of the guiding axle  021  so as to be able to pick up electrical power from the slot.  
           [0003]    In addition, a power unit  03  is usually installed somewhere at the outer side of track  01 , of which the positive and negative electrodes are connected to the conducting strips  012  that are on both sides of the slot  011  respectively. When the two cars  02  (A, B) are placed on the track  01  and their guiding axles  021  are fitted into slots  011 , the conducting brushes  022  of the cars  02  (A, B) contact the conducting strips  012  on both sides of slots  011 . When the switch of power unit  03  is turned on, cars  02 A and  02 B will be powered up and start to run along the slots  011  of the track  01 . Conventionally the power unit will be battery-powered or connected to an electrical mains supply.  
           [0004]    To enhance the fun of the slot car, a race between the two cars can be arranged. The cars can run quite quickly along straight line parts of the track, but they need to be run more slowly in the curvilinear parts of the track so as to prevent the cars from running off the track due to centripetal force. To achieve this, the conventional slot cars are also equipped with a control unit for adjusting car speeds, which may function may be implemented through the following two methods: One of the methods is to connect a slide resistance to the circuit formed by the slot car, in which case the speed of the car can be altered by changing the resistance value of the slide resistance and the strength of current in the circuit which thus changes the strength of current provided to the car (see FIG. 3). Another method is to change the voltage of the input circuit, which can be realized using option switch  03 , as shown in FIG. 4. When the switch  03  contacts with A, B, C respectively, the voltage of the input circuit will change simultaneously and thus the speed of car  02  will be changed accordingly.  
         SUMMARY OF THE INVENTION  
         [0005]    According to the present invention there is provided a slot car toy comprising a track having at least one slot and at least one toy car adapted to engage said slot and run on said track, wherein said toy car is adapted to receive electrical power from said slot and wherein manually driven electrical power generating means is provided for supplying electrical power to said slot.  
           [0006]    In preferred embodiments of the invention the electrical power generating means may comprise, for example, a hand-operated generator, a foot-operated generator or a treadmill-operated generator.  
           [0007]    Preferably a plurality of tracks may be provided with respective manually driven electrical power generating means associated with each track.  
           [0008]    In a preferred embodiment the slot car toy may also comprise a sound generating means powered by the manually driven electrical power generating means. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    Some embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which:— 
         [0010]    [0010]FIG. 1 is a schematic diagram of a conventional product,  
         [0011]    [0011]FIG. 2 shows a conventional slot car on a track,  
         [0012]    [0012]FIG. 3 is a circuit diagram showing a first known method of speed control,  
         [0013]    [0013]FIG. 4 is a circuit diagram showing a second known method of speed control,  
         [0014]    [0014]FIG. 5 is a schematic diagram showing an embodiment of the present invention,  
         [0015]    [0015]FIG. 6 is a schematic diagram of a method of power transmission according to a first embodiment of the present invention,  
         [0016]    [0016]FIG. 7 is a schematic diagram of a method of power transmission according to a second embodiment of the present invention,  
         [0017]    [0017]FIG. 8 is a schematic diagram of a method of power transmission according to a third embodiment of the present invention,  
         [0018]    [0018]FIG. 9 is an illustration of one possible hand-operated electric generator for use in an embodiment of the present invention, and  
         [0019]    [0019]FIG. 10 is an illustration of another possible hand-operated electric generator for use in an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0020]    As shown in FIGS. 5 and 6, a toy slot car system according to an embodiment of the present invention includes track  1 , at least one car  2 , a manually-driven electric generator  3 , and an electrical sound-effect unit  4 . Track  1  is a closed path loop that is formed by a number of connected track elements. Each track element includes at least one slot  11 , preferably two parallel slots, so that when the track elements are connected together to form the complete track  1  two slots  11  are formed on each of which a car may be run so that two cars can use the track at the same time and can race each other as is known in the prior art.  
         [0021]    As in the prior art, conducting strips  12  are installed on both sides of each slot  11  and each car  2  is equipped with a guiding axle  21  at the bottom for guiding the car along a slot and on both sides of which there are conducting friction elements or brushes  22  that serve as the power electrodes of car  2  and pick up electrical power from the slots  11 .  
         [0022]    In contrast with the prior art where batteries or a mains supply are used to provide the power to the slots, in a preferred embodiment of the present invention the anode and cathode of power outputs from a manually-driven electric generator are connected to conducting strips  12  that are on both sides of slots  11  and this manually-driven generator is used to power a car.  
         [0023]    In an embodiment of the invention a hand-operated electric generator can be used for the manually-driven electric generator  3  which can also be designed as a foot-operated or treadmill-style electric generator.  
         [0024]    [0024]FIG. 6 shows one possible example of a hand-operated electric generator. In this embodiment a hand wheel  301  is turned by a user and this rotation will be transmitted to the rotating shaft of a micro-generator  305  through the gear case  302 , drive gears  303  and  304 . Consequently the micro-generator  305  outputs power to the electrical sound effect unit  4  and track  1  respectively via the power cord  306  through a series of intermediate circuits. FIG. 9 illustrates a hand-operated generator that is adapted to be held by a user. The hand wheel  301  is provided on one side and a number of control buttons  40  for various functions (eg sound effects) can be provided. Alternatively the hand-operated generator may be a table-top model as shown in FIG. 10.  
         [0025]    By the term “manually-driven” electrical generator is any form of generator that outputs electrical energy in response to human effort and exertion. In addition to hand-operated generators other types such as foot-operated and treadmill-style generators could also be used.  
         [0026]    The operating principles of foot-operated and treadmill-style generators are basically the same as those of hand-operated electric generators as shown in the example of FIG. 7. When a user steps on the pedal  311 , the belt roller  312  attached to the pedal rotates with the belt  313  which thus drives the rotating shaft  315  of the motor  314 . The motor  314  supplies power to the electric sound effect unit  4  and track  1  via the power cord  316 .  
         [0027]    The structure and operating principle of treadmill-style generator are basically the same as that of the foot-operated generator as shown by the example of FIG. 8. The treadmill-style generator utilizes the mechanical energy that is generated by a user running on the plate of the treadmill-style generator to drive the rotating shaft  325  of the motor  324  with the belt roller  321 ,  322  and the belt  323 , which thus makes the motor  324  output power and transmit the power to the electric sound effect unit  4  and track  1  via the power cord  326 .  
         [0028]    When using an embodiment of the present invention, the user should place the car  2  on the track  1  with the guiding axle  21  of the car  2  fitting into the slot  11 , so that the conducting friction elements  22  on the car  2  contact the conducting strips  12  that are on both sides of the slot  11 . Once the manually-driven electric generator is activated, it will generate the electric current and the car will be powered on by the conducting strips  12  and the conducting friction wafers  22 , after which the car starts to run along the slot  11  of the track  1 . During the course of running, the guiding axle  21  serves as the navigator of the car  2  to prevent it from derailing from the slot  11 , whilst the conducting friction wafers  22  always keep in contact with the conducting strips  12  so that the power supply to the car  2  will not be interrupted. The speed of car  2  can be changed during the course of running by altering the rotation speed of the hand-operated electric generator, treadmill-style generator or foot-operated generator in order to change their output current, in which case the user will be able to manually control the car speed at any time as the circumstances may require. This would involve users&#39; participation which helps to increase the fun of the toy as well as helping users to perform body exercise during the game.  
         [0029]    In addition, the electric sound effect unit  4  is also powered by the manually-driven electrical generator so that, the electric sound effect unit  4  will start to play music (or other sounds) when the manually-driven electric generator  3  starts to generate electricity. Moreover, the loudness, volume, and frequency of the music can be altered by changing the current generated from the manually-driven electric generator  3 , so that the music sounds rich and varied which adds more fun.  
         [0030]    In order to provide more options for the players, the toy slot car system can also retain the structure of battery power used in existing products and a battery compartment is provided for this purpose. The player can then alternatively choose batteries or manually-driven electric generator  3  for supplying power to the slot car.