The initial sketch is shown above, and features two ”axis holders”, through which the rotational axis of the esaape lever and pendulum goes. Initial sketch of the upper frame including escapement lever. This proved to be the most challenging part of the project, making the over 20 parts of the upper part fit into the same frame. Another is to actually have them fixed and fit in a specific location, and having all parts move together correctly. One thing is to create individual parts that fits together on paper. Again I designed the initial idea in Fusion 360, and made sure that the spacing fit with the escapement gear previously made. Two end stops are then added to the other end, giving the rod an axis of rotation. Stability is very important in this design, since any flexibility could make the gears jump out of place. A wedge is then added to the end, and a pin keeps the structure fixed. A ”spacer” is then added, making sure the ”gear 2" does not interact with the other gear. The ”stop” makes sure the first gear goes to a fixed position. The ends also allows for a nail to go through. This makes them just fit on the beams, holding them together without any need for glue. The end stops are fitted on the beams through two square holes with a fitting of -0.2 mm. Sketch of how the axes are fixed without glue.īy adding two ”end stops”, the friction area against the frame will be minimized. To make them rotate, a nail would be connected in both ends, being held in place by the frame. To minimize the amount of glue needed, I designed a rod system, going through the centre of the gears and fixing them in position. Since the gear train had to be connected to the same axis as the escape gear, I had to fix them in some way. You’re propably wondering what those beams sticking out of the escapement are in the above picture. Even though the cardboard was very weak and hard to fit, the prototype gave a good idea on how the system would work. As this was the critical part to finish first, I exported the. The screen shot was then imported to Autodesk Fusion, and used as a base for sketching. I changed the variable in the program, and took a screen shot of it. Since the escape mechanism needs two periods to move one tooth, the gear would need 30 teeth. I wanted the pendulum to have a period of one second. Since I had absolutely no idea on how to model this special gear, I downloaded a Wolfram CDF demonstration model, and used the software to model the gear. Source: Wikimedia Commons Link to heading Here’s a gif, because it’s absolutely impossible to visualize it in your mind: The lever, connected to the pendulum, only allows the gear to do one tick per pendulum period. The escape mechanism consists of a lever and a gear. Since my sources descriped the escape mechanism as the most tricky part, I figured it would be best to start here. Instead I based the overall design on Brian Law’s Youtube channel on wooden clocks. Since all these parts are codependent, designing them individually proved to be very challenging. Here’s a quick sketch of my initial design: The latter is not a top priority in this project, because of the limited time given. And to have the hour hand and minute hand go together correctly, additional clock gears have to be added. To be able to gear up or gear down the rotations done by the pendulum to actually be able to tell the time, a gear train is required. The details of this function will be explained later. Therefore, an escape mechanism is required, typically being an escape lever combined with an escape gear. Giving the weight a free fall would just make the clock go very fast, and having to rewind the weight every 2 seconds. This is done by a weight, giving torque to the gear attached to the pendulum. The pendulum does not swing by itself, and needs some sort of power applied to it. The period time can be determined by some simple mathematical formulas, and has impact on the dimensions for the pendulum. The time for one complete cycle called a period. To keep the time, a pendulum oscillates from side to side. The mechanical clock consists of several main functions. With that in mind, you can download all the parts as pdf by clicking this link. If you choose to use my design, please share your experiences with me!įurthermore, I never had time to clean up the schematics, so you may not be able to get this working without modifying some of the parts yourself. I think that I could have got it working by further tweaking of the counter-weights etc. This means that while the gear mechanisms themselves works, the clock was never able to run by itself. Due to the time constraints of the project period, I never got the escape mechanism to work properly. Disclaimer: The clock was designed and built in approx.
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