CN105893741A - Lead screw health guaranteeing method capable of realizing whole process real-time data statistics - Google Patents

Abstract

The invention discloses a lead screw health guaranteeing method capable of realizing whole process real-time data statistics. The method comprises the following steps of performing data whole process real-time collection, performing lead screw position interval division, and performing interval division statistics on collected data; solving the standard deviation of each interval statistics index value of a lead screw, and representing the unbalance work condition of the lead screw by the standard deviation; and judging whether the standard deviation of each interval statistics index value is greater than the preset threshold value or not, and performing prediction judgment on the relative health state of each interval and the work condition of the lead screw. The method can be realized inside a numerical control system without adding any additional sensors and storage equipment; the external interference is avoided; the use is convenient; the unbalance work condition of the lead screw can be monitored, and the automatic warning function can be provided; the method can be used for guiding and regulating the position of a work table; and the work condition abnormity of the lead screw due to the long-period work of the work table of a machine tool in a certain position is avoided, so that the service life of the lead screw is prolonged.

Description

A kind of leading screw health care method of omnidistance real time data statistics

Technical field

The invention belongs to digital control system, machine tool technology field, more particularly, to a kind of omnidistance real-time The leading screw health care method of data statistics.

Background technology

In the feeding transmission system of Digit Control Machine Tool, leading screw drive workbench, it is achieved platen Movement, leading screw is as a critical component in Digit Control Machine Tool feeding transmission system, its working condition Transmission accuracy can be directly affected, if the working condition of leading screw occurs abnormal, the feeding of lathe will be passed Dynamic precision impacts.

It practice, leading screw is in running, due to the speed of each position of leading screw, acceleration and Varying in size of leading screw institute's stress, the service condition causing each position of leading screw is the most different, therefore Digit Control Machine Tool is during long-term processing uses, and workbench is in certain position long-term work so that this The leading screw life-time service of position, leading screw is in unbalanced duty in the range of total travel.If Leading screw is chronically at unbalanced duty in the range of total travel, and the performance that will accelerate leading screw is moved back Change, reduce the service life of leading screw, and the feeding transmission accuracy of lathe can be impacted, and then fall The crudy of low production and production efficiency.

Summary of the invention

It is an object of the invention to provide a kind of leading screw health care method, use visual process to realize Monitoring to working condition unbalanced in the range of leading screw total travel, for operator to leading screw total travel Health status analysis, judge and make maintenance provide instruct.

For achieving the above object, it is proposed, according to the invention, provide the leading screw of a kind of omnidistance real time data statistics Health care method, its step includes:

(1) the real-time sampling data that lathe runs, the position of lathe feed shaft when running are obtained including leading screw Put, speed and load current；

(2) according to required precision, leading screw is divided position interval, if leading screw is divided into N number of interval；

(3) data step (1) gathered, are mapped to each interval of division；Add up each interval each Sampled point electric current scalar value is cumulative with speed cone value product；Totalization formula is:

$C_i=\underset{j=1}{\overset{P_i}{\Σ}}(I_{ij}\×V_{ij})$

Wherein, C_iFor the value of statistical indicant that i-th is interval, I_ijThe jth interval for falling into i-th The electric current scalar value of sampled point, V_ijFor falling into the speed cone value of the interval jth sampled point of i-th, P_iThe data amount check interval for being mapped to i-th.

(4) making normalized, it is contemplated that increase in time, each interval statistics desired value can present The trend always increased, for ease of analyzing, by each interval statistics desired value normalization in step (3) In [0,1] numerical intervals, normalization formula is:

$M_{ci}=\frac{C_i-C_{min}}{C_{\max }-C_{min}}$

Wherein, M_ciFor the value of statistical indicant that the i-th after normalization is interval, C_minFor all interval statistics Minima in desired value, C_maxFor the maximum in all interval statistics desired values；

(5) standard deviation sigma of each interval statistics desired value after calculating normalization:

$\begin{array}{cc}\mathrm{\σ}=\sqrt{\frac{1}{N-1}\underset{i=1}{\overset{N}{\Σ}}{(M_{ci}-\mathrm{\μ})}^2}& \mathrm{\μ}=\frac{1}{N}\underset{i=1}{\overset{N}{\Σ}}{M}_{ci}\end{array}$

Wherein, the arithmetic mean of instantaneous value of each interval statistics desired value after μ is normalization；

(6) according to σ value and C_maxDetermine the working condition of leading screw:

σ value is the biggest, illustrates that the leading screw unbalanced working level in whole stroke range is the biggest, leading screw Overall operation conditions is the poorest；

C_maxThe interval health status at place is worst, and this interval is it may happen that fault.

Further, in step (6), it determines σ value size, method is to differentiate that whether it is more than presetting Threshold value, be to illustrate that the working condition of leading screw is abnormal；Otherwise illustrate that the working condition of leading screw is normal；

Further, threshold value, is the lead screw transmission precision decline of the working condition according to lathe and test And set when affecting processing parts size precision；

Further, real time data acquisition, statistics and analysis realize inside digital control system.

Further, each for leading screw interval statistics desired value curve or figure can be demonstrated, intuitively see Survey the unbalanced working condition of leading screw, and predict the relative health in each interval of leading screw.

In general, by the contemplated above technical scheme of the present invention compared with prior art, due to Leading screw is divided position interval, with the standard deviation table of each interval statistics desired value that by stages statistics obtains Levy the leading screw unbalanced working condition in whole stroke range, and can be by comparing each interval system of leading screw The size of meter desired value, it was predicted that the relative health in each interval of leading screw, can obtain the most useful Effect:

1. the omnidistance Real-time Collection of lathe service data can realize with statistics inside digital control system, is not required to Adding any extra sensor and storage device, the data of acquisition are the internal automatically controlled numbers of digital control system According to, standardization, reliably, not by external interference, easy to use；

2. can monitor the unbalanced working condition of leading screw in real time, the unbalanced working condition of leading screw is existed Visualization display on numerical control device interface, and automatic early-warning can be provided, it is achieved to numerical control machine tool lead screw Health care；

3. may be used for instructing the position adjusting workbench, it is to avoid platen is long-term in certain position Work causes the working condition of leading screw extremely, thus extends the service life of leading screw.

Accompanying drawing explanation

Fig. 1 is the enforcement flow chart of steps of the present invention.

Fig. 2 is the block diagram of Z axis leading screw each interval statistics desired value of specific embodiment.

Detailed description of the invention

In order to make the purpose of the present invention, technical scheme and advantage clearer, below in conjunction with accompanying drawing And embodiment, the present invention is further elaborated.Should be appreciated that described herein specifically Embodiment only in order to explain the present invention, is not intended to limit the present invention.Additionally, it is disclosed below Just may be used as long as technical characteristic involved in each embodiment of the present invention does not constitutes conflict each other To be mutually combined.

Embodiment, as a example by the feed shaft Z axis of lathe.

A kind of leading screw health care method of omnidistance real time data statistics, its step successively:

(1) the real-time sampling data that lathe runs are obtained, the position of machine Z-axis when running including leading screw, Speed and load current；The present embodiment obtains CK4055 numerically controlled lathe in real time and runs ten hours every day, Run the data of ten days；

(2) according to required precision, leading screw is divided position interval, the Z axis silk of CK4055 numerically controlled lathe Thick stick total travel is 440mm, divides total travel leading screw with 22mm for spacing, and the interval number of division is 20, Interval, position is [-440 ,-418], [-418 ,-396] ..., [-44 ,-22], [-22,0]；

(3) data step (1) gathered, are mapped to each interval of division；Add up each interval each Sampled point electric current scalar value is cumulative with speed cone value product；Totalization formula is:

$C_i=\underset{j=1}{\overset{P_i}{\Σ}}(I_{ij}\×V_{ij})$

Wherein, C_iFor the value of statistical indicant that i-th is interval, I_ijThe jth interval for falling into i-th The electric current scalar value of sampled point, V_ijFor falling into the speed cone value of the interval jth sampled point of i-th, P_iThe data amount check interval for being mapped to i-th.

(4) making normalized, it is contemplated that increase in time, each interval statistics desired value can present The trend always increased, for ease of analyzing, by each interval statistics desired value normalization in step (3) In [0,1] numerical intervals, normalization formula is:

$M_{ci}=\frac{C_i-C_{min}}{C_{\max }-C_{min}}$

Wherein, M_ciFor the value of statistical indicant that the i-th after normalization is interval, C_minFor all interval statistics Minima in desired value, C_maxFor the maximum in all interval statistics desired values；

(5) standard deviation sigma of each interval statistics desired value after calculating normalization:

$\begin{array}{cc}\mathrm{\σ}=\sqrt{\frac{1}{N-1}\underset{i=1}{\overset{N}{\Σ}}{(M_{ci}-\mathrm{\μ})}^2}& \mathrm{\μ}=\frac{1}{N}\underset{i=1}{\overset{N}{\Σ}}{M}_{ci}\end{array}$

Wherein, the arithmetic mean of instantaneous value of each interval statistics desired value after μ is normalization；

(6) according to σ value and C_maxDetermine the working condition of leading screw:

First, totally judge, the biggest according to σ value, unbalanced in whole stroke range of leading screw is described Working level is the biggest, and the overall operation conditions of leading screw is the poorest；Practice can set threshold value, it determines σ is No more than the threshold value preset, it is to illustrate that the working condition of leading screw is abnormal；The work of leading screw is otherwise described Situation is normal；Threshold value can fail according to the lead screw transmission precision of the working condition of lathe and test and affect Set during processing parts size precision；The present embodiment is according to the working condition of CK4055 numerically controlled lathe and examination Testing the decline of lead screw transmission precision to affect processing parts size precision, the threshold value set is as 0.6.

Second, interval judgement, C_maxResiding interval, its health status is worst, it may occur that fault.

The present embodiment, the block diagram such as accompanying drawing 2 of each interval statistics desired value of calculating.Further, calculating is returned The standard deviation sigma value of each interval statistics desired value after one change is 0.3681 < 0.6, and the work of leading screw is described Situation is normal.By accompanying drawing 2, can intuitively find out C_maxThe interval at place is [-198 ,-176], permissible Prediction, compares other positions interval, and this interval health status of leading screw is worst, it may occur that therefore Barrier.

In the present embodiment, real time data acquisition, statistics and analysis realize inside digital control system.

Select as one, each for leading screw interval statistics desired value curve or figure can be demonstrated, directly The unbalanced working condition of observation leading screw, and predict the relative health in each interval of leading screw.

Select as one, described normalized, other method can be used to carry out.

Additionally, real-time data acquisition, the statistics and analysis of other feed shaft leading screws of lathe be may be used without Said method.

As it will be easily appreciated by one skilled in the art that and the foregoing is only presently preferred embodiments of the present invention, Not in order to limit the present invention, all made within the spirit and principles in the present invention any amendment, etc. With replacement and improvement etc., should be included within the scope of the present invention.

Claims (4)

1. the leading screw health care method of an omnidistance real time data statistics, it is characterised in that comprise the steps:

(1) the real-time sampling data that lathe runs, the position of lathe feed shaft, speed and load current when running are obtained including leading screw；

(2) according to required precision, leading screw is divided position interval, if leading screw is divided into N number of interval；

(3) data step (1) gathered, are mapped to each interval of division；Add up the cumulative of each interval each sampled point electric current scalar value and speed cone value product；Totalization formula is:

Wherein, C_iFor the value of statistical indicant that i-th is interval, I_ijFor falling into the electric current scalar value of the interval jth sampled point of i-th, V_ijFor falling into the speed cone value of the interval jth sampled point of i-th, P_iThe data amount check interval for being mapped to i-th.

(4) normalized, normalizes in [0,1] numerical intervals by each interval statistics desired value in step (3), and normalization formula is:

Wherein, M_ciFor the value of statistical indicant that the i-th after normalization is interval, C_minFor the minima in all interval statistics desired values, C_maxFor the maximum in all interval statistics desired values；

(5) standard deviation sigma of each interval statistics desired value after calculating normalization:

Wherein, the arithmetic mean of instantaneous value of each interval statistics desired value after μ is normalization；

(6) according to σ value and C_maxDetermine the working condition of leading screw:

σ value is the biggest, illustrates that the leading screw unbalanced working level in whole stroke range is the biggest, and the overall operation conditions of leading screw is the poorest；

C_maxThe interval health status at place is worst, and this interval is it may happen that fault.

Leading screw health care method the most according to claim 1, it is characterised in that in step (6), it determines σ value size, method is to differentiate that it, whether more than the threshold value preset, is, illustrates that the working condition of leading screw is abnormal；Otherwise illustrate that the working condition of leading screw is normal；Described threshold value, is that the lead screw transmission precision of the working condition according to lathe and test fails and affects setting when processing parts size precision.

Health care method the most according to claim 1 and 2, it is characterised in that described real time data acquisition, statistics and analysis realize inside digital control system.

Health care method the most according to claim 1 and 2, it is characterised in that each interval statistics desired value can visualize display with curve or patterned mode on numerical control device interface.