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There is an excellent description of the castle clock in this article on muslimheritage.com. It describes the full workings of the clock, including all of the mechanisms for things such as doors opening and closing and for the sun moving across the clock. The most interesting part, for me at least, is how he used water to make a relatively accurate ...


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The mechanism is called an "escapement", and part of its function is that the gear imparts energy to the swinging teeth in order to keep the pendulum (or whatever) moving in spite of any frictional losses it might have. Note that in your diagram, the gear teeth impinge on a curved surface on each of the swinging teeth. Note also that as a result, the ...


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In principal it should not be very difficult to adapt an off the shelf mechanism like a mechanical alarm clock or kitchen timer. They will already have some sort of latching mechanism to activate the bell after the elapsed time so it should be a simple matter to adapt this to close an electrical contact. Having said that I'm not entirely convinced that a ...


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It is common for timing belt systems to have a tensioner pulley, effectively an idler mounted on a sprung radial arm. In most situation this is just to take up slack from wear and stretch and generally ensure consistent tension throughout its life but if you allow enough travel it could certainly achieve what you want. Depending on the amount of travel you ...


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What you want is called the belt's neutral axis. The neutral axis is what coincides with the pulley's pitch circle. You have to look this up for each belt, because it depends on the way the belt is made. But if this is a synchronous belt and pulley system, you are doing things backwards. The pulley profile is the established standard, and the belt guys have ...


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The rotation of shaft 119 with the cam changes the load on the valve springs, but it also changes the location of the fulcrum of the lever assembly parts 101, 103 and 104. As the bulk of the cam moves closer to the pivot 104, the travel at the right end of 101 will be increased compared to the travel when the bulk of the cam is on the opposite side. You ...


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The amount of information you specified is too limited. If you had more information, maybe you could do it, but not as stated. Machining tasks can vary greatly. I can imagine some parts where it might literally take hours to get work piece fixtured in the machine, but then the actual machining operation takes only a few minutes (e.g. a giant part for a ship ...


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No, because the number to be produced changes the percentage ie the setting up time can be longer than the machining time for 1 piece but 3% for 100 pieces and 0.003% for 1000 pieces...


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I tried both ways, idlers and slide, with and without additional spring. A) Idler with spring tends to oscillate when load torque is not constant (it is rarely constant). B) Sliding motor and spring is less sensitive to torque fluctuations due to non-zero friction in slide. C) Idler without spring have some minor disadvantages: accurate and not-so-compact ...


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Use a flap valve - allows air out and if you design the "catch" correctly then won't allow air to pass until a certain load or depression is achieved.


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