I finally have some time to work on this project. The minutes section will be controlled via the rotary switch. It has 30 positions, each with 4 switches. Row one will be used for the ones indicator: 0-9. Row 2 will be used for the tens indicator: 0-2. Row 3 will also be used for the tens indicator: 3-5. At one complete rotation a leaf switch is engaged which can be used to control a relay. This relay switches from row 2 to row 3. I was a bit confused on how to do this with relays & only one pulse. I found the solution here: http://www.emil.matei.ro/onof2.php
A good read and best diagram I’ve found to explain this operation. Version 1 is the one that I’m going to use. No ‘load’ is necessary as the relays I’ll be using have 3 switches, each has a normally open & normally closed contact. The pulse to trigger the rotary switch will come from a digital clock that comes in a tube like package. The current idea for the hours section is to use a solenoid to control a cam with 12 sections. Each section is to have a micro switch. If I can find a 12 section motorized switch, maybe from a neon sign or telephone system, I may use that instead. Next step is to put together the power supply & test the pulse generator. Also thinking about aesthetic design & how to set time. There’s still much to be decided & many problems to solved.
The shifter has been added. It requires the use of a cable with a cylinder at one end, like a mountain bike brake cable, not a standard Sturmey Archer cable. The barrel adjuster needed to be drilled out for the wider cable. A wheel, with a custom bracket, has been added at the axle to guide the cable. This arrangement is slightly unsatisfactory. It works, but the small chain, at the indicator rod, is coming almost straight out of the nut. This makes it posable for the indicator rod to unscrew, although this is unlikely. The shifter was designed for this type of frame, however it doesn’t fit very well. It is currently mounted on one of the top tubes. The bracket fits better then if it were over both tubes, but it can rotate. The two holes on the shifter had to be ground to fit better. I may ground off some more metal and mount over both top tubes. The rear brake cable has been moved to run behind the shifter. It needs to be shortened. Also, the fulcrum is held in place via a pipe clamp. Looking for a proper clip. I may make my own. One that can also hold the rear brake cable. I now understand why the 1930s car horn has a relay. The current would be very high though the switch. The relay works and will be kept. A battery needs to be acquired as well as a Battery Tender. A lock is to be added to the power, to prevent random people from pressing the horn button, when the bike is locked up. I would like to give a nice shock to the button, for such people. However, as this will not kill then I fear for retribution to my tricycle. Compromises don’t come easy. I’ve noticed that the same type of people are using the flat bed to hold their coffee and standing/sitting on it. Maybe I can add a remote to the horn to give them a mild heart attack. One more thing, the old school white grips are on there way, via the postal system.