RE: Alarm Clocks

A few days off and we get a new group project. This one is less conceptual and more hands-on: reverse engineer something.

The first challenge was defining that “something.” We finally decided on an alarm clock. We wanted something that had some interesting mechanical features rather than a device that worked only because of circuitry. What we ended up was actually a good mix – there was a small integrated circuit inside our analog bell alarm clock but there were plenty of interesting mechanical features. I will list some of the ones that I found the most interesting/innovative:

1. The motor used an offset lobe to cause the motion of the clapper (yes, that’s what that thingy that rings the bell is called). It reminds me of the lobes used in engines that move the push rods up and down. While there are so many solutions to the problem of transferring the circular motion of a motor into a back and forth motion of a clapper, this was an elegant solution that may have been adopted from other technologies (the adaptability of solutions is just one reason why experience in engineering is so important).  
2. The snooze button was not something the used actually pressed. Rather the clock used the snooze button as a third leg and the user could press down on the top of the clock to activate it. Again, this is not a complicated system – it’s just not necessarily the first solution most people would think of. These engineers wanted a simple product but that didn’t mean they weren’t going to think about it much.
3. The gears for the hands of the clock didn’t have an “actual” motor powering them. By this I mean that there was a coil that powered the gear train via a magnet. Yes, we all know that electricity and magnetism can do things like that, but I didn’t expect to find that a coil would be a better solution than a motor.

As for the merits of reverse engineering, there are pretty significant pros and cons. In terms of the pros, you get more experience and learn a lot. However, you have to be careful if you are going to design a similar product to not get caught thinking there’s no better way to do the design. After all, a design can always be improved. Of course, some designs are better to be re-started than improved.

Overall, regarding alarm clocks, they’re a lot more complicated (or simple) than you might have thought.