Appearance is main function index

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One, the overview understands commonly used definition in index of function of the appearance on project type (weigh precision again) , change difference, sensitivity will describe. Appearance is versed in desired result appearance also is air officer accuracy normally, change difference and sensitivity 3. Becoming poor is to show appearance is measured variable (can understand to input signal) when never reaching same numerical value with direction for many times, the biggest difference between appearance indicated value is worth, perhaps saying is appearance is below the circumstance with changeless outside ambient, the parameter that be measured by small to big change (to character) with the parameter that be measured by arrive greatly little change (retrorse character) abhorrent degree, both difference becomes poor for appearance namely, change the compare per cent that differs size to take the biggest absolutely error and range of appearance staff guage. The main reason that becomes poor to arise among them is the clearance of compose of appearance Wei motive, the friction of athletic component, stretch component lag. Get victory is worn improve of appearance production technology ceaselessly, especially of microelectronics technology introduce, complete electron changed a lot of appearance, without movable component, appearance of number of imitate appearance instead is waited a moment, become poor so it is so not important that this index appears in intelligence appearance and highlighted. Sensitivity is to show appearance is right the acute degree that the parameter that be measured changes, perhaps saying is the reaction ability that changes to the volume that is measured, it is to be below stable state, output change increment changes to the input the ratio of increment: Sensitivity of appearance of the S- in type; Δ L- appearance outputs metabolic increment; Δ X- appearance inputs metabolic increment; Sensitivity also says " enlarge compares " sometimes, also be the slope that appearance nods each on static characteristic and apt line. Increase enlarge multiple to be able to heighten appearance sensitivity, pure the basic function that increases sensitivity not to change appearance, namely appearance precision did not rise, can appear sometimes instead oscillation phenomenon, cause output to be not stabilized. Appearance sensitivity should hold proper amount. However to appearance user, industry of bearing of enterprise of such as chemical industry will tell, appearance precision is a main index admittedly, but in be being used actually, the stability that often emphasizes appearance more and but * sex, because chemical enterprise detects,with the process control appearance is used at metric amount to not much, and many is to be used at detecting. Additional, use the measuring instrument in process control system its stability, but * sex is more more important than precision. 2, definition section calls accuracy appearance precision, weigh accuracy again. Accuracy and error can say is twin brother, because have the presence of the error, just have definition this concept. Appearance accuracy is the exact level that appearance measured value approachs true value in a word, use normally relative to 100 minutes of errors (also call opposite amount to the error) express. Be as follows relative to formula of 100 minutes of errors: The δ in type - detect in the process relative to 100 minutes of errors; (rear sight upper limit is worth - staff floor level is worth)- - appearance measures range; Δ X- absolutely error, it is X1 and standard of the parameter that be measured are worth measured value of the parameter that be measured the difference of X0. Alleged mark fiducial value is accuracy compares the numerical value that the standard watch of times measures tall 3~5 of the appearance that be measured. Appearance precision is concerned with absolutely error not only, and with the measurement of appearance limits is concerned. Absolutely error is big, relative to 100 minutes of errors big, appearance accuracy is low. If absolutely error is identical two appearance, its measure limits to differ, so measure range large bearing is opposite 100 minutes of errors are small, appearance definition is high. Accuracy is the index of a quality with very main appearance, commonly used accuracy class comes standard and express. Accuracy class is the biggest mix relative to sign of take out of 100 minutes of errors % . The grade that by the country unified regulation differentiates has 0.

005, 0.

02, 0.

05, 0.

1, 0.

2, 0.

35, 1.

0, 1.

5, 2.

5, 4 wait, appearance accuracy class indicates commonly go up in appearance staff guage or sign, be like, , 0.

5 wait, the number is smaller, explain appearance definition is higher. Want to enhance appearance definition, be about to undertake the error is analysed. The error can be divided normally change for negligent error, delay sum of errors of error, system random error. Negligent error is the error that points to to in measuring a process, be caused artificially, can overcome first, concern without what with appearance itself second. Delay changes because appearance is in-house,the error is the process causes ageing of yuan of parts of an apparatus, it can be used change yuan of parts of an apparatus, component or through ceaseless and corrective try to overcome and be eliminated. Systematic error is to point to right same when the parameter that be measured undertakes for many times repetition metrical, the error with appears numeric size or same symbol, or the error that changes by definite pattern, but the accidental element place that had be notted know by people at present is caused, size of its numerical value and property are not fixed, estimate hard, but can adopt statistical method from theoretic estimation its are opposite detect the influence of the result. Source of error basically points to systematic sum of errors random error. When expressing precision with the error, it is to point to the sum of error of system of random sum of errors. 3, reproduction sex (repeatability)   measures reproduction sex is to be in different measure a condition to fall, be like different method, different observer, detect in what differ the environment is right same when the quantity that is detected undertakes detecting, its measure the level that agrees as a result. Measure reproduction sex to be sure to become the main function target of appearance. Metrical accuracy is the accuracy of appearance not just, it still includes all sorts of factors the influence to measuring parameter, it is integrated error. Press with dynamoelectric Ⅲ difference change send implement for exemple, following type place show integrated error: The referenced precision that condition of ± 1) ℃ issues the E0-(25 in type, ± 0.

25% or ± 0.

5% ; E1- environment temperature is right at 0 o'clock (4mA) influence, ± 1.

75%;e2- - environmental temperature is right full span (20mA) influence, ± 0.

5%;e3- actuating pressure is right at 0 o'clock (4mA) influence, ± 0.

25%;e4- - actuating pressure is right full span (20mA) influence, ± 0.

The numeric generation of 25%; general E0, E1, E2, E3, E4 enters type (1-1-4) : This explains 0.

25 class are dynamoelectric Ⅲ changes send implement the effect that because temperature and actuating pressure change,measures precision by 0 original.

25 level fall for 1.

87, explain sex of this appearance reproduction is poor.

It also explains right same when the volume that is measured undertakes detecting, because measure a condition to differ, get the influence of environmental temperature and actuating pressure, its gauge the rate difference that agrees as a result.

If use difference of a whole intelligence to change,send implement replace on dynamoelectric Ⅲ difference is pressed in the exemple change send implement, corresponding type (the E0= ± in 1-1-4) 0.

0625% , e1+e2= ± 0.

075% , e3+e4= ± 0.

15% , era enters type (1-1-4) gets ± of = of E put together 0.

18% , should press than dynamoelectric Ⅲ difference change send implement ± of = of E put together 1.

87% small much, difference of demonstrative whole intelligence is pressed change send implement undertake compensating to temperature and pressure, fight environmental temperature and actuating pressure ability strong. Can depict the interference rejection faculty of appearance with appearance reproduction sex. Measure reproduction sex to use inaccuracy to be spent surely normally will estimate. It is right as a result of the presence that measures an error that inaccuracy is spent surely the rate that cannot be affirmed by measured value, can use variance or standard deviation (of Deng variance square root) express. All heft cent that does not spend certainly is two kinds: A kind: The heft B that decides with statistical method kind: With blame statistic method affirmatory heft sets A kind the variance that does not spend certainly is Si2 (standard deviation is Si) , b kind the corresponding and approximate variance that inaccuracy goes vacationing to exist surely surely is for Ui2(standard deviation (Ui) , synthesize inaccuracy to spend surely for: 4, stability is inside formulary work requirement, the ability that certain property retains changeless along with time calls appearance stability (degree) . Appearance stability is the index of a function that industry of chemical enterprise bearing cares very. The environment that uses instrument as a result of chemical enterprise is compared relatively abominable, change of the medium temperature that is measured, pressure also is compared relatively big, devoted in this kind of environment appearance is used, the certain part of appearance maintains changeless ability to be able to be reduced along with time, the stability of appearance can drop. Give into or token appearance stability still has no mensurable value now, chemical enterprise uses instrument normally the stability that 0 drift will come to to measure meter. Appearance investment moves one year in null does not have drift, contrary appearance investment does not run 3 months, appearance null changed, explain appearance stability is bad. The stand or fall of appearance stability matters to the scope of application of appearance directly, affect chemical production directly sometimes, appearance stability is bad to cause influence often the impact that double appearance precision drops to be produced to chemical industry is even big. Appearance stability is bad that appearance maintains a volume big also, it is the thing that bearing industry hopes to appear least of all. CNC Milling