In Mechanical Watch the energy source is a spiral spring located in a barrel with the gear edge. At watch winding up, the spring twists, and at untwisting, the spring actuates the barrel, rotation of which actuates all clockwork.
The main defect of the spring engine is irregularity of the spring untwisting speed that leads to inaccuracy in watch rate. Also, in a mechanical watch, accuracy of rate depends on set of factors, such as temperature, position of the watch, wear and tear of parts and other. Therefore, for mechanical watch, it is considered normal to have divergence with exact time by 15-30 seconds a day, and the best result - 4-5 seconds a day. At that mechanic watch with correct use and periodic service will be able to work more than 25 years. Also, it needs to notice that today most of mechanic watches are automatic. It means that it doesn`t need the hand winding of spring.
Watches of brand KLEYNOD with auto winding are completed with Swiss movements ETA of 2824-2 and 2892-A2 calibers. The quantity of ruby stones in the movements is 25 and 21 conformity. The daily average divergence of watches accuracy which are equipped with the above movements at the temperature of 20±5 ºC is within the range of ±5 to ±25 sec/day (for caliber 2824-2) and of ±12 to ±30 sec/day (for caliber 2892-A2). The period of power autonomy with full winded spring is not less than 38 hours (for movement ETA 2824-2) and 42 hours (for movement ETA 2892-A2). Movements ETA are equipped with shock-proof system of the balance axis and automatic winding up device of spring mover.