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The main principle of lubrication
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How is the oil supplied onto the chain?
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The wheel turns and a sensor creates one pulse per turn. That is one puls all 5ft......1
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A small electronic circuit buffers the sensor pulses and divides the pulses by the factor of 16.....2
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C-Control
processes the pulses, controls the pump and drives the display......3
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The pump lubricates the chain, but only at a speed more than 25mls/hr...... 4
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General information
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In nearly any electrical or
electronical device on the market, you will find in the meanwhile a microcontroller installed. And that’s independant whether thats a washing machine, a stereo, a car or a machinery control unit - in all
these devices, these microcontrollers perform tasks, that were processed in the past by very complex standard electronic circuits. Today one microcontroller is enough, equipped with the appropriate
software, and it can perform nearly any task. The C-Control
system, sold by Conrad Electronics, is such a microcontroller system, which is very flexibel, inexpensive, upgradeable for the future and programmable by newcommers.
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The “job” which that microcontroller
has to take over in the Schwaboiler system is relatively easy. - Count the wheel turns of the front wheel and supply a certain amount of oil based on a pre-configured distance with a pump onto the chain.
That’s all.
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How does that all work?
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How are the wheel turns counted?
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In the meantime the small bicycle
speedometer of the type BC700, which measures the speed very exactly with the help of a small magnet installed at the brake disk,
is well know amongst motorbike riders. The same principle is used here. A small magnet at the brake disk switches a reed-relay, which is fastened to the front fork. For our application we use the reed relay (Conrad part.no.503703). The pulses then are buffered with the help of two 7400 NAND gates and divided by 16. A 4-bit counter counts the pulses. The Microcontroller selects, reads this counter and sets it to zero after each data read out.
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A short mathematical excercise.
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On the basis of a wheel perimeter of
approx. 1600mm and a maximum speed of the motorcycle of 300km/h, there is a maximum of 84m/s. The magnet installed at the brake disk passes based on that facts the reed relay approximately 50 times per
second, which corresponds to a frequency of 50Hz. The pulses are divided by 16, which corresponds to a counting rate of 3.2Hz. The 4-bit counter can maximally count up to to 16 count before he runs into
an overflow. Therefore this counter must be read and resetted latest after a time of 5 seconds by the microcontroller. The microcontroller reads data in periods of milliseconds. Therefore an overflow of
the counter may not happen at any time.
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How are the pulses processed?
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The program that runs on the
microcontroller is very flexibly and can be easily modified. In our case it sums up the incomming pulses and compares the sum with the value, which the driver has programmed before. If the count value is
alike or larger as the reference value, the oil pump becomes unlocked, but there is no oil yet supplied to the chain.
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The issue with the speed.
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It would be not so nice if that value
is just in that moment reached when you stop in front of a traffic light. Just think for a moment. The chain does not move, and the pump is supplying oil to it. Not a good idea.. This would be a bad and
dangerous situation. Therefore the program takes care that the pump can operate only if the speed of the motorcycle is higher than 30km/h.
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The pump supplies the oil.
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If both conditions are fulfilled, the
microcontroller triggers the relay for the pump and oil is supplied for the amount of time which the driver has preset before.. A value of “all 25km” is equivalent to a quantity of 5ml of oil and is
absolutely sufficient. Of course this value can be changed and adapted what ever the driver prefers, which mainly would be depend on the weather or ground the motorbike is used in.
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