Modified gear system

It is a modified gear system for rickshaws/bicycles to reduce effort in pulling the load.

When one pedals in anti-clockwise direction the rickshaw/bicycle runs like an ordinary rickshaw/bicycle, and when pedaling is done in the reverse direction the modified gear system comes into effect by reducing the effort but moving the vehicle forward only. Effectively it also acts as brake during reverse pedaling by restricting rearward movement of rickshaw over slopes. However, if one wants to enjoy freewheel action during reverse pedaling, like ordinary bicycle/rickshaw, he needs to disengage gear by pulling the clutch wire.

This unit is an assembly that replaces the conventional front sprocket of rickshaw. It consists of a main shaft, a front sprocket drive, a reversible gear assembly, a planet gear assembly, a clutch subassembly housed enclosed inside a single covering. The annular ring of the planetary gear system has 44 teeth, with a pitch of 1.4 cm. There is a 6 cm diameter cavity in the central hub with two free wheels attached to the shaft. There is a small gear with 24 teeth attached to the free wheel. When the rickshaw is pedaled in forward direction, only one freewheel gets activated and this works just as in conventional rickshaws.

When encountering potholed or inclined surfaces, the user commences with reverse pedaling.  This activates the other inner free wheel. This in turn drives the smaller gear with 24 teeth in reverse direction, which meshes with a pinion on the clutch plate with identical teeth and it rotates in opposite direction. Being attached to the inner teeth of sprocket – the motion is passed on to the cycle wheel, which rotates in the forward direction. This action of the pinion also facilitates locking and prevents backward movement of the wheels on inclined surfaces.

When the road is smooth and for an easy ride (and speed is more important than torque) the rickshaw puller would pedal normally and this transfers human power through pedal to sprocket at same RPM after bypassing the mechanism. When there is need of high torque and low speed as in the case of upward slope, potholed or muddy road conditions, the driver has to start reverse pedaling to activate this unit.

NIF supported Nishant for prototype development and facilitated its testing at BIT, Mesra Ranchi where the performance was found to be satisfactory. User trial was also undertaken by driving the rickshaw on a steep gradient, the result of which was also satisfactory. However, the report added that value addition in design could be done to increase the efficiency.

The innovativeness  lies in using ‘reverse pedaling” selectively in tough terrain to change power shaft direction and drive the vehicle forward with lesser user effort. This has been achieved by using the epicyclical gear train arrangement realised in a simple but effective manner. A patent (1714/KOL/2007) was filed in his name by NIF in 2007.

The journey thus far

His father never wanted him to waste time in pursuing such things. Instead he wanted him to study well and later work like his brother, who is a software engineer. But his love for doing such creative things was more than any thing else. He did like studies but not much. He mostly used junk and scrap to make different things, but whenever money was needed to buy something from the market, he had to approach his grandfather or purchase it from his pocket money. Many times, he also had reservations in his heart about the feasibility and success of his ideas but always gave in to his inner feeling.

His friends did not take much interest while he did something new but whenever he completed it and showed to them they did take good notice of it. His maternal cousins were quite appreciative and he could easily discuss his ideas with them. His two younger paternal cousins always looked at him with curiosity.

Apart from developing the modified gear system for cycle-rickshaw for pedaling uphill, his other notable designs include a low cost water filter, an arrangement to wash clothes fitted inside a bucket and a battery operated wrench. He wishes to get the technology of this innovation licensed so that it gets replicated soon and thousands of rickshaw pullers get benefit from it, proving himself to all his detractors at the same time.

Nishant was also felicitated during the 22nd Shodh Yatra in Bihar in January 2009 for his creativity.