jake 247
spring powered bike
Like the product jumping stilts is used to gain explosive power in jumping or running, I believe the same will be true for the bicycle.
Fig 1 The sprocket with the pedals are not shown, they would be stock. In red is the mounting point of the elongating spring or bungee cord. In green is the spring/cord. In purple is the crank attached to the rear wheel so the crank and wheel can spin at a faster speed than the hub temporarily. In this pic the spring is adding power to what you are applying to the pedals.
The bike will travel faster because there will be temporary burst of power from the spring, momentum from these burst will make the bike travel further in the same amount of time (faster).
Fig 2 This shows the spring being compressed although this will slightly slow the bike, momentum is traveling forward and the losses will be less then the gains of speed. What you lose in torque compressing the spring you gain it right back when the spring recoils including the speed of the spring recoiling, there would be a burst in torque in Fig 1 of the spring AND the foot pedals fully. Equal torque lost then gained (in Fig 1) netting no loss torque (Fig 1 and 2 combined), but speed is gained because the spring recoils faster than the foot pedals. Also inertia from the weight of the rider will help compress the spring.
Fig 3 is a top view of the rear tire crank and spring setup.
*Typical sizes could a 6" radius of the purple crank attached to the wheel or more. Spring weight could be calculated. If I were to guess - Math 1/2 riders power goes to the wheel 1/2 goes to the spring. Divide that by the gear ratio 4/1 or 4. Multiply that by 2 (6" crank) because the wheel would be 2x the size (1' radius) of the crank.
If it works for jumping stilts it should work here.
spring powered bike
Like the product jumping stilts is used to gain explosive power in jumping or running, I believe the same will be true for the bicycle.
Fig 1 The sprocket with the pedals are not shown, they would be stock. In red is the mounting point of the elongating spring or bungee cord. In green is the spring/cord. In purple is the crank attached to the rear wheel so the crank and wheel can spin at a faster speed than the hub temporarily. In this pic the spring is adding power to what you are applying to the pedals.
The bike will travel faster because there will be temporary burst of power from the spring, momentum from these burst will make the bike travel further in the same amount of time (faster).
Fig 2 This shows the spring being compressed although this will slightly slow the bike, momentum is traveling forward and the losses will be less then the gains of speed. What you lose in torque compressing the spring you gain it right back when the spring recoils including the speed of the spring recoiling, there would be a burst in torque in Fig 1 of the spring AND the foot pedals fully. Equal torque lost then gained (in Fig 1) netting no loss torque (Fig 1 and 2 combined), but speed is gained because the spring recoils faster than the foot pedals. Also inertia from the weight of the rider will help compress the spring.
Fig 3 is a top view of the rear tire crank and spring setup.
*Typical sizes could a 6" radius of the purple crank attached to the wheel or more. Spring weight could be calculated. If I were to guess - Math 1/2 riders power goes to the wheel 1/2 goes to the spring. Divide that by the gear ratio 4/1 or 4. Multiply that by 2 (6" crank) because the wheel would be 2x the size (1' radius) of the crank.
If it works for jumping stilts it should work here.