Marigo Round (Working)

3.2 WORKING

         An electricity generating playground device, indicated generally at in accordance with the present invention for generating electricity when children play on the playground device. The playground device  can be a merry-go-round a bicycle, a treadmill, and the like. Additionally, the playground device  can have a cyclically movable part , an electricity generator  and indicated generally at . The cyclically movable part  can be moved in reciprocal or repetitive cycle by children playing on the playground device  . For example, in the case of a merry-go-round, the cyclically movable part can be a rotatable upper deck that can be turned by children pushing on the deck. The electrical generator  can be operable coupled to the cyclically movable part   The generator  can be operated by the cyclically movable part  so as to generate electricity when the cyclically movable part is moved through a repetitive motion. In one aspect, the generator  can be a permanent magnet generator and alternator that can have a low start up speed due to low cogging and resistive torque design. Additionally, the generator can be a gearless, direct drive, and low RPM generator, as known in the art.

          The playground device  can also include a battery  electrically coupled to the electricity generator . The battery  can receive and store electricity from the electricity generator  . In one aspect, the battery  can be a 12 V lead acid battery, or a deep cycle RV or marine battery. In another aspect, the battery  can be a rechargeable valve regulated lead-acid battery with a qualified electrolyte. Other batteries, as known in the art can also be used, so long as the battery is rechargeable. It will be appreciated that as children play on the electricity generating playground device  , the children can move the cyclically movable part  in uneven and irregular cycles in a given unit of time. This can cause an irregular output from the generator  which can cause less than ideal conditions for charging a battery  . Additionally, as the activity level on the playground device  ebbs and flows, the frequency of complete cycling of the cyclically movable part  can fall below a minimum threshold for generating power from the generator  in which case the drag from the generator  can cause the cyclically movable part  to stop cycling or become difficult to move. Moreover, in an effort to generate as much electricity as possible from the play of the children on the playground device  , the generator  can cause drag on the playground device that significantly dampens the free cycling or momentum driven cycling of the cyclically movable part  making the cyclically movable part difficult to move. These problems can cause children or adult supervisors to lose interest in the playground device  . For example, if the playground device is inefficient at producing electricity, adults supervisors may not view the device as anything more than a toy. Additionally, if the cyclically movable part  is difficult to move, children may view the playground device as a work tool instead of a toy, and, thus, choose to decrease energy expenditure on the device.

          The current generated by the generator in order to limit the amount of kinetic energy from the cyclically movable part that is converted to electricity. Thus, the duty cycle controller can be programmed or set to limit the electrical current generation to a level approximately equal to about 25% of the kinetic energy expended by children playing on the playground device. The inventors have found that by limiting the amount of current generated by the generator to about 25% of the kinetic energy of children playing on the playground device allows for adequate electricity generation to charge the batteries and does not induce so much drag or dampening on the playground device that operation of the cyclically movable part turns from fun to work for the children playing on the device.