The Millennium Time Project: Alternative Time Measuring Mechanisms by Miltiadis A. Boboulos - HTML preview

16. Diagram 14 16.1. The designer’s logbook

A coil spring is most often used in clocks and only rarely in some special devices like timers where it could also be linear. (Note: a coil spring is a spring wound in a drum or loosely around a so-called Archimedean spiral. Some timer mechanisms involve such springs, like for example in cameras .

We decided to adopt an arrangement comprising a “linear” coil spring as the

 

The Millennium Time Project

liquid at a height (length of blade 19) h. The rack 5 is hinged via the hinge 11 to the arm 12 positioned on a horizontally movable bracket hinge 13 on the slide 16 attached to the device frame. A roller 15 is positioned at the end of the arm 12, which is in a fork-shaped guide along X-14 on a stand attached to the outer surface of the cylinder 18. The stand 14 is inserted in a slide along the Y axis (vertically) of the device frame.

16.2.2. Operation

When the spring 8 is actuated it pulls on the slide 3 and rotates the screw 6
via the nut 2. This causes the reducer Z₁ to Z₄ to rotate along with the blade 19 of the hydraulic brake 18. The nut 2 moves 18 vertically downwards via the arm 12
and guide 14 thus changing h so the rotation speed of Z₄ and hence, the speed of the screw 8 are maintained constant. The rack 5 moves the gear 4 and rotates the scale 7 indicating hand.

When the spring is compressed it can be re-loaded by means of the handle 10 of the screw 8. Adjustment to the correct time is accomplished by means of