Tuesday, February 19, 2013

About stopwatches mecanism

In any mechanical stopwatches need to distinguish four major parts:

    engine (spring or weight)
    the transmission gear
    regulator conditioning fluidity
    distributor or down, on the one hand, the pulses are transmitted from the motor controller are necessary to maintain the oscillation of the latter, and, on the other hand, subordinates move the gearbox, and therefore the action of the motor patterns of vibration control.

Meter time in the narrower sense is the regulator. Gears, sealed with arrows dial - counter-measured units of time control. Recognizing the daily rotation of the earth on its axis is strictly uniform, we are in it, we have only to compare the scale intervals or time units. Usually the unit of time are seconds, 1/86400 of the day. On a different track of time, the star, middle, true day - see the time.

Regulators stopwatch movements are arranged so that they measured out the time intervals equal to the whole or a second, or a half, a quarter or a fifth of a second. If for some reason the controller will measure shorter time intervals, the counter will show more of them in this time period. In this case, the clock, as they say, go ahead. If the interval is longer than the specified control - clock is slow. Agreeing on the initial moment of the day, in other words, about the moment when the hour meter must read zero elapsed time units arrive at the concept of Amendment hours. It is positive if the clock backward, negative - if left on. Changing the clock correction for a certain period of time is called the course hours (eg, daily, weekly, hour course). Progress is positive if the clock is slow, negative, if the clock goes forward. Progress expresses precisely measured out the evasion control periods from the accepted one. The amendment is the conditioned hours and, in addition, at any time by simply moving the minute hand counter correction clock can be made less than one minute.

Dignity of the same hours is small, and most importantly - constant speed. Stroke of good astronomical clocks and chronometers should preferably be independent of changes in temperature, pressure, humidity, random shocks, abrasion axis mechanism, thickening of lubricating oil, the molecular changes in different parts of the mechanism, etc. Astronomical Clock is divided into two main types:

    'Permanent', in which the driving force is the weight of weights and pendulum control
    "Portable" where the movement is produced by the elastic force is gradually unfolding spring, and adjustable elastic vibrations, thin spiral connected to the so-called. balance (see below).

First timers are called in astronomy "clock" in the narrow sense of the word, or "pendulum". They are located at the observatories at constant astronomical instruments (see Practical Astronomy), mounted on stone pillars, or in the wall clocks are often placed in the basement of the observatory, in order to protect against possible changes in temperature ("normal" hours.) Cellar visit only for winding hours, as even the heat of the body can affect their progress. Reading the same hours, that is, the "hits" of the pendulum (always second), compared with other clocks with a microphone installed in the basement and connected to the phone (the phrase, although generally accepted, but it is not true. Blows "ticking" makes no pendulum ( controller), and the mechanism of descent). With proper installation and care of "permanent" astronomical clock should have daily rate of 0.3 s, and its daily changes should not exceed one-hundredth of a second.

Timers of the second type are called chronometers. Distinguish between "table" or box-chronometers (size of about 1 ½ -2 Decima. Diameter, 1 Decima, height, a simple swing the balance lasts ½ seconds), and pocket chronometers (the size of a well-known, commonly so-called. Chetyredesyatniki, ie complete Double Vibrations lasts 0.4 seconds, a simple swing - 1/5 seconds). Quality pocket chronometers on average sensitivity as table below. Chronometers are in determining geographic locations of places, the work portable astronomical instruments (see Practical Astronomy), in determining the time and longitude at sea, etc. Dining chronometers for ships are placed on weight gain of Cardan. Constant stopwatch ("pendulum") almost exclusively, and chronometers in most cases governed by the stellar second time - the so-called. "Star" stopwatches and chronometers. Less likely to use "average" online chronometer (ie reaching the average time). Choice is due to the convenience of observation or treatment for those or other problems in astronomy.

In stopwatches and chronometers are still certain astronomers are appreciated, but not sharp, and without unnecessary noise hits ("ticks"). As the best masters of astronomical clock or chronometer to be named Kesselsa, Peel, Dent, Thiede, Hovyu (Howüh), Knobliha, Frodshema, Nardena. Creators of the "highest" stopwatchmaking and movement: Peter Leroy (born Pierre Le Roy), John Harrison, George Graham (born George Graham), Dyutertr, John Arnold (born John Arnold), Ferdinand Berthoud (born Ferdinand Berthoud ) Juergensen.

No comments:

Post a Comment