A new turn signal/brake light project

B

bigbikeseat

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I been working on this for several months now. It is a turn signal kit that uses a 6 volt front wheel shimano dynamo hub that recharges a 1800mah 6 volt battery pack. It has an automatic charging circuit. The turn signals use a 6 volt 24 led. The front are amber, and the rear are red. When the brakes are applied, both rear lights come on, but the front amber lights don't. If the brakes are applied, and a turn signal is applied, then 1 rear brake light stays on, and the opposite light flashes. Both front and rear lights flash as turn signals. It works just a like car. The flasher is a 555 timer. The circuit has several pc mini relays rated at 1 amp. With the running lights on and brake lights on, it draws about 750ma. The motorized bicycle turn signal switch was bought on ebay for about 20 bucks. The kit also has a red brake light indicator led that lets you know that the rear brake lights are working. On the mini project box mounted on the middle of the handlebars , it has both left and right green led turn signal indicators that help you to find the off position of the turn signal slide switch.
 
Terrific! Sounds like a nice set-up.

You ought to give some photos of key components, or other ways of identifying them, so that those who want to can follow in your footsteps.
 
I'm going to put up some of the circuits later....the 555 timer/ flasher, and the automatic charger, but right now I have the prototype mounted on the bike. I'm going to road test it for a little while to make sure it is seaworthy. I'm hoping to have a printed circuit board made sometime in the future. I want to make sure the relays can take the street pounding of the bike. I want to get the cost down too. The front hub dynamo/ disc brake is $250 plus. I want to make my own 6v led lights too, maybe $10 a piece. The ones I have cost $140 for four. With the cost of the relays, resistors and IC's and turn signal switch, this project can easily top $475. If a battery is used instead of the dynamo hub, a tremendous savings can be had. The dynamo hub would be useful for a long ride or night ride . Hopefully I can get the price down to $100 for the whole thing, without the dynamo hub.
 
here's a rough copy of the flasher circuit 140408_0002.jpg
 
Here's a copy of the automatic battery charger. It is not my design, but I was fortunate to find it on the internet. When it reaches a preset voltage, the relay kicks off, disconnecting the charging circuit. It kicks on at 3.5v, and kicks off at 5.75v, just the way I set it up. SWAGATAM INNOVATIONS is where this circuit came from.140408_0003.jpg The transistor I used is a 2n 2222.
 
Here is a very very rough copy of the switching circuits used to activate the LED lights. The mini pc relays have built in diodes, so I didn't show them on the schematic. 2 relays (4 and 5) had to be added because the turn signal switch was a spst device, and it was not compatible with what I had in mind.140408_0006.jpg
 
I built a 12v system the first time around, and it was very bright. The batteries tend to be much larger and heavier, and there is no way to recharge with a dynamo hub, because I could not find one that was 12v. I opted for the 6v system because the battery pack can be small (AA size), and it recharges quickly. The 6v system, with the store bought led lights that I have, seem to be very directional, subject to up and down tilt. The light intensity varies with the angle that you look at it. That's why I want to make my own led lights with reflectors behind the LED's. The amber LED lights don't shine as strong as the red Led lights. Another obstacle is the .7v voltage drop due to the diodes that each LED light has . It is necessary due to the interaction between the lights. Static glitches occur if the diodes aren't used. The brake switch also needs a .05 uf cap to eliminate glitches also. So the answer to your question is The 6v red LED's work in daylight, and the 6v amber ones are marginal. These lights I bought are small. With larger lights, I believe the problem can be overcome.
 
I don't know much about caps, resistors, diodes, switching circuits, etc. And I use hand signals for turning. But I did build a very simple 12v lighting system with a battery and a generator to charge it. I will lay out the components the best I can. I guess I'll start with the generator. It's a 12v bottle generator, the kind that spins off the tire. I ran the positive wire from the generator to a scooter regulator. The regulator converts the genny's AC to DC. Then I ran a wire from the regulator to a power distributor, used in car audio, with a 4A inline fuse. The battery, headlight and brake light are all connected to the power distributor as well. The brake light is controlled via a brake lever with a built-in switch, so it's probably already got a cap in it. The headlight is controlled via an automotive toggle switch. The brake lever originally housed a wiring harness that controlled the brake light, headlight via a high/low beam, turn signals and horn. I gutted the wiring harness and dremeled the crap out of the housing until the toggle switch would fit in there. The toggle part sticks out of the hole where the horn button used to be. All components are grounded to the frame. I also made a custom battery gauge. It's the kind designed to fit into a boat dashboard. I took apart an old tail light and epoxied the gauge into the back part of the tail light housing. The gauge has an on/off switch which is a sp/st rocker switch I ordered from sick bike parts. I added the on/off switch for two reasons. One, even though the gauge is only supposed to draw less than a milliamp per hour, I don't want to take the chance of it draining my battery. Two, I don't have to stare at it while driving. The battery is a 12v, 1.2Ah SLA battery. I chose a small capacity battery for two reasons. One, it is small and lightweight. I don't know if you've ever seen a Whizzer battery, but it's the same size as a Whizzer battery. This enabled me to fit my battery on my luggage rack and slide it partway under my seat. It is a little less than half the width of my luggage rack, and I have it secured with a large hose clamp. Two, a smaller capacity battery charges more quickly, so with daily use, it pretty much stays above 13v. It holds a charge well. I have not used my bike all winter, nor have I brought the battery inside to charge, and it's still at 12.5v. I've compared my onboard battery meter to a digital multimeter, and it's accurate within (+/-) 0.1v. Hey, I'm not trying to one-up your project here, just trying to give you some ideas and inspiration for future projects or if you decide to change this one up a bit at some point. Good luck with your project!
 
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