CN100591472C - Energy-saving method for idle operation between adjacent phase for digital control machine tool - Google Patents

Abstract

The invention provides a method for implementing shutdown for energy conservation in idle running between adjacent process steps of a numerical control machine. The method comprises the following steps: before machining, according to the operation speed of a mainshaft obtained by a machining process and the spacing interval between the adjacent process steps determined when the numerical control machine programs, the idle running time between the adjacent process steps is obtained; and the control time and the energy conservation percentage when reboot after shutdown for energy conservation isimplemented between the adjacent process steps are calculated by a testing data table and a curve fit method. When the energy conservation percentage is a positive number, a shutdown instruction anda subsequent reboot instruction are embedded in a numerical control program according to the control time, thereby achieving the effect of the energy conservation of the machine. With regard to the problem that a main transmission system has energy loss in idle running between the process steps of the numerical control machine, the method adopts a mode of the reboot after the shutdown to reduce the idle running time of the machine in the mechanical manufacturing process and to achieve the aim of energy conservation.

Description

A kind of Digit Control Machine Tool halt energy conservation implementing method in no-load running period of adjacent process steps

Technical field

The present invention relates to mechanical manufacturing field, the implementation method of energy savings when being the operation of a kind of lathe.Shut down energy-conservation implementation method when being specifically related to no-load running between the Digit Control Machine Tool adjacent process steps.

Background technology

China's machine tool owning amount ranks first in the world, and the power consumption total amount is surprising.Simultaneously, a large amount of surveys show: lathe energy average utilization is low, less than 30%.For realizing " green manufacturing " strategy, it is significant to seek feasible lathe power-economizing method.ZL03117163.X invention disclosed name is called the invention of " a kind of machining system energy-saving and noise-reducing method ", from the angle of system, by rational management between lathe and the workpiece and arrangement, obtains the energy-saving effect of whole system of processing; This method is considered to carry out energy-conservation from whole machining system angle, do not change the energy loss of lathe itself.ZL89104006.4 invention disclosed name is called the invention of " controller for driving motor of machine tools ", and machine motor is replaced with two motors of different capabilities, makes two motors alternately or operation simultaneously according to the load size, thus saves energy.But this method has increased the complexity of machine motor, and has changed the design of original machine motor.ZL90211626.6 invention disclosed name is called " lathe energy-saving power supervising device " utility model, discloses a kind of power monitor device of saving the lathe electric energy, and when lathe underloading or zero load, power supply passes through the single-circuit transformer step-down, thereby realizes energy-conservation; This device is primarily aimed at machine motor and takes conservation measures.The no-load running process extensively exists between the Digit Control Machine Tool work step, when withdrawing between car controlling bed work step, tool changing and feed, if the speed of mainshaft is constant, generally just is in the no-load running process in full; And for example between the CNC milling machine work step during lifting workpiece, generally also be in the no-load running process.In the said process, because the change of cutting parameter between different work steps can produce actions such as withdrawing, tool changing, feed.When these actions are carried out,, do not have stop motion yet, still have energy to pass over the motion requirement of keeping them, caused the loss of lathe energy from machine motor though main transmission system of machine tool does not carry out the production and processing action.The main transmission energy loss is a kind of energy loss widely in the unloaded process of lathe, also is to cause one of low immediate cause of lathe capacity usage ratio.

Summary of the invention

At between the Digit Control Machine Tool adjacent process steps during no-load running; the main transmission energy loss causes the present situation of unnecessary waste; shut down energy-conservation implementation method when the purpose of this invention is to provide no-load running between a kind of Digit Control Machine Tool adjacent process steps; during by no-load running between the Digit Control Machine Tool adjacent process steps; stop the operation of main transmission running, reach the purpose of saving the lathe energy loss.

Technical scheme of the present invention is: a kind of Digit Control Machine Tool halt energy conservation implementing method in no-load running period of adjacent process steps, it is characterized in that, and obtain main shaft running speed n according to processing technology before the processing _jThe determined work step interbody spacer time is obtained no-load running time T between adjacent process steps when reaching the Digit Control Machine Tool programming ₀, and pass test data table and curve fitting method are calculated and are implemented to shut down control time and the energy-conservation percentage of restarting after energy-conservation between adjacent process steps; When energy-conservation percentage is positive number, in numerical control program, embed halt instruction and follow-up restart instruction between this work step by the control time, reach the effect of saving the lathe energy.Comprise the steps:

(1) select m (m is a natural number) level machine spindle speed, by the real data collection, obtain two data test charts of lathe: main transmission no-load power table and main transmission system of machine tool under the m level speed of mainshaft start to rotation speed n from stopped status _jTransit time and loss of energy table;

(2) test data that step (1) is obtained carries out curve fitting, and obtains to shut down the preparation formula of energy-conservation decision-making and enforcement, i.e. main transmission loss of energy computing formula E under each speed of mainshaft of lathe _Uj=(A ₁n _j ²+ B ₁n _j+ C ₁) T ₀, main transmission system of machine tool starts to rotation speed n from stopped status _jComputing formula T transit time _0j=A ₂n _j ²+ B ₂n _j+ C ₂, and main transmission system of machine tool starts to rotation speed n from stopped status _jLoss of energy E _0jComputing formula E _0j=A ₃n _j ²+ B ₃n _j+ C ₃Wherein, A ₁, B ₁, C ₁, A ₂, B ₂, C ₂, A ₃, B ₃, C ₃The known constant that obtains for the curve match;

(3) computational methods of control time and energy-conservation percentage:

1. according to the computing formula in above-mentioned (2) step, obtain between this adjacent process steps main transmission system of machine tool energy consumption E during the no-load running _Uj, main transmission is restarted to rotation speed n after shutting down _jEnergy consumption E _0j

2. calculate energy-conservation percentage K _j=1-E _0j/ E _Uj

3. work as K _jDuring for positive number, take to shut down and restart strategy, and will comprise the halt instruction in being engraved in when shutting down and comprise according to T _0jCalculate restart the time follow-up restart instruction in being engraved in be embedded in the middle of the numerical control program.

The inventive method is made of the preparation and the concrete operations step two large divisions of the computing formula before implementing.

1. computing formula obtains

1. the preparation of test data table

Select m (as m=10, m is a natural number) level machine spindle speed, main transmission no-load power test data table (table 1) and the main transmission system of machine tool set up under the lathe m level speed of mainshaft start to rotation speed n from stopped status _jTransit time and the energy test tables of data (table 2) that consumed.M numerical value is big more, and the computing formula that then obtains at last is accurate more, but workload also can correspondingly increase.

Main transmission no-load power test data table under each speed of mainshaft of table 1 lathe

The speed of mainshaft (rev/min)	n 1	n 2	…	n j	…	n m
							The main transmission system of machine tool no-load power (watt)	P u1	P u2	…	P uj	…	P um

In the table, P _Uj---machine spindle speed is n _jThe time no-load power

Table 2 main transmission system of machine tool starts to rotation speed n from stopped status _jTransit time and the energy test tables of data that consumed

The speed of mainshaft (rev/min)	n 1	n 2	…	n j	…	n m
							Start-up time (second)	T 01	T 02	…	T 0j	…	T 0m
Consumed energy (joule)	E 01	E 02	…	E 0j	…	E 0m

In the table, T _0j---machine tool chief axis is from starting to n _jThe used time of the transient process of rotating speed

E _0j---machine tool chief axis is from starting to n _jThe transient process institute consumed energy of rotating speed

2. adopt the mode of curve match, utilize the data acquisition energy-conservation decision-making of shutdown of table 1 and table 2 and the formula of enforcement.

According to the rule that measured data presented, adopt quadratic function to carry out match and have convenience of calculation and the high characteristics of precision, so order

P _uj＝A ₁n _j ²+B ₁n _j+C ₁ (1)

T _0j＝A ₂n _j ²+B ₂n _j+C ₂ (2)

E _0j＝A ₃n _j ²+B ₃n _j+C ₃ (3)

N represents the rotating speed of machine tool chief axis in this section no-load running time in the formula, is known quantity; A ₁, B ₁, C ₁, A ₂, B ₂, C ₂, A ₃, B ₃, C ₃Be unknown quantity.Main transmission rating formula, main transmission system of machine tool started to rotation speed n from stopped status when formula (1), (2), (3) were respectively between the Digit Control Machine Tool adjacent process steps no-load running _jComputing formula and the energy computing formula that consumed transit time.

By measured data and least square method, have

$f(A_1,B_1,C_1)=\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{[P_{\mathrm{uj}}-(A_1{n_j}^2+B_1{n}_j+C_1)]}^2---\left(4\right)$

$f(A_2,B_2,C_2)=\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{[T_{0j}-(A_2{n_j}^2+B_2{n}_j+C_2)]}^2---\left(5\right)$

$f(A_3,B_3,C_3)=\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{[E_{0j}-(A_3{n_j}^2+B_3{n}_j+C_3)]}^2---\left(6\right)$

Formula (4), (5), (6) are found the solution following equation group respectively

$\left\{\begin{array}{c}\frac{\&PartialD;f}{{\&PartialD;\mathrm{<figure-callout\; id="1"\; label="A"\; filenames="C2008100703020009H1.png"\; state="\{\{state\}\}">A</figure-callout>}}_1}=0\\ \frac{\&PartialD;f}{{\&PartialD;\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="C2008100703020009H1.png"\; state="\{\{state\}\}">B</figure-callout>}}_1}=0\\ \frac{\&PartialD;f}{{\&PartialD;\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="C2008100703020009H1.png"\; state="\{\{state\}\}">C</figure-callout>}}_1}=0\end{array}\right.$ $\left\{\begin{array}{c}\frac{\&PartialD;f}{{\&PartialD;A}_2}=0\\ \frac{\&PartialD;f}{{\&PartialD;B}_2}=0\\ \frac{\&PartialD;f}{{\&PartialD;C}_2}=0\end{array}\right.$ $\left\{\begin{array}{c}\frac{\&PartialD;f}{{\&PartialD;A}_3}=0\\ \frac{\&PartialD;f}{{\&PartialD;B}_3}=0\\ \frac{\&PartialD;f}{{\&PartialD;C}_3}=0\end{array}\right.$

Can solve A ₁, B ₁, C ₁, A ₂, B ₂, C ₂, A ₃, B ₃, C ₃Value.

Then, between the adjacent process steps of being tried to achieve during no-load running the main transmission power function carry out time integral, main transmission energy dissipation function in the time of can obtaining between adjacent process steps no-load running.As shown in Figure 1, because main transmission power invariability during no-load running between adjacent process steps, main transmission energy dissipation computing formula is in the time of can obtaining between adjacent process steps no-load running

$E_{\mathrm{uj}}=\underset{t_i}{\overset{t_{i+1}}{\&Integral;}}{P}_{\mathrm{uj}}\left(t\right)\mathrm{dt}=P_{\mathrm{uj}}(t_{i+1}-t_i)=(A_1{n_j}^2+B_1{n}_j+C_1)T_0$

Wherein, T ₀Be the no-load running time between adjacent process steps, by actual processing technology decision.

Among the figure, t _iThe initial moment of unloaded period between the expression adjacent process steps, t _I+1The finish time of unloaded period between the expression adjacent process steps.

So far, the preparation of shutting down the formula of energy-conservation decision-making and enforcement is just finished.These formula all remain unchanged for a long period of time and are available.

2. the operation of shutting down energy-conservation decision-making and enforcement realizes

1. before processing,, obtain this to speed of mainshaft n during no-load running between adjacent process steps according to processing technology and the numerical control program worked out _jWith the no-load running time T ₀

2. with speed of mainshaft n during no-load running between adjacent process steps _jThe special equation that substitution step 1 is set up calculates between this adjacent process steps main transmission system of machine tool power E during the no-load running _Uj, main transmission is restarted to rotation speed n after shutting down _jUsed time T _0jAnd energy consumption E _0j

3. calculate energy-conservation percentage K _j: K _j=1-E _0j/ E _Uj

4. work as K _jDuring for positive number, then can take to shut down conservation measures.But in practice,, generally want energy-conservation percentage K for fear of the influence of the frequent starting of lathe to lathe _jGreater than certain value K ₀(as K ₀=20%) just shuts down power-save operation the time; Halt instruction and follow-up restart instruction are embedded in the middle of the numerical control program, and in certain machine tooling process as shown in Figure 2, the shutdown that should embed is t constantly _i, restarting is t constantly _I+1-T _0jWork as K _jFor negative or less than K ₀The time, then do not take to shut down conservation measures.

5. if this is not latter two work step of whole process to adjacent process steps, then return step 1., restart decision-making, prepare processing otherwise finish to shut down.

The present invention shuts down energy-conservation plan method when having set up between a kind of Digit Control Machine Tool work step no-load running; the energy loss problem of main transmission when this method is conceived to no-load running between the Digit Control Machine Tool work step; the mode that adopts shutdown to restart reduces the lathe no-load running time in the machine-building process, reaches the purpose of energy savings.Except that setting up computing formula, subsequent operation is very easy.

Description of drawings

Energy consumption schematic diagram during no-load running between Fig. 1 two work steps;

Fig. 2 machine tooling process main transmission power curve.

The specific embodiment

Below in conjunction with a specific embodiment the present invention is further specified.

Be on the numerically controlled lathe of the CK6136 that produces of Nanjing No.2 Machine Tool Plant the present invention to be tried out a model, process on probation is as follows:

1. the preparation of computing formula

1. the foundation of test data table

The range of speeds of this lathe is 0 rev/min---1500 rev/mins, be divided into 10 grades, and test collection by table 1 and table 2 requirement respectively, obtain table 3 and table 4.

Main transmission no-load power table under the table 3 numerically controlled lathe speeds of mainshaft at different levels

The speed of mainshaft (rev/min)	150	300	450	600	750	900	1050	1200	1350	1500
											The main transmission system of machine tool no-load power (watt)	80	120	150	173	210	230	275	300	345	365

Table 4 numerically controlled lathe following start-up time of the speed of mainshaft at different levels and energy consumption table

The startup rotating speed (rev/min)	150	300	450	600	750	900	1050	1200	1350	1500
											Start-up time (second)	0.82	1.4	2.1	2.88	3.52	4.14	4.64	5.02	5.64	6.48
Consumed energy (joule)	69.84	157.28	283.92	432.88	653.16	855.7	1143.7	1357.1	1777.3	2123.4

2. the data that record of his-and-hers watches 3 and table 4 carry out curve fitting, thereby obtain

The no-load power equation of main transmission under arbitrary speed of mainshaft

E _uj＝(-6.67×10 ^-6n _j ²+0.227n _j+40.6)T ₀ (7)

Cause the used timing equation of this rotating speed from shutting down startup

T _0j＝-2.9×10 ^-7n _j ²+0.00377n _j+0.97 (8)

And the equation of the energy that is consumed

E _0j＝-0.00045n _j ²+2.7745n _j-1267.8 (9)

In addition, consider to start impact and the life-span influence of main transmission, energy-conservation percentage COEFFICIENT K to lathe ₀Be defined as 20%.Above-mentioned formula is put things right once and for all, and can use for a long time.

2. shut down energy-conservation decision-making and enforcement

Processing is during a certain workpiece on above-mentioned CK6136 lathe, according to technological requirement, need be under n=1250 rev/min of rotating speed processing excircles and end face, promptly this process has two work steps.According to technological requirement, the total time of withdrawing, tool changing and feed is 60 seconds between work step, i.e. T ₀=60 seconds.The moment t when cylindrical tooling step finishes _i=75 seconds, the initial moment of end face processing was t _I+1=135 seconds.Concrete decision-making and implementation step are as follows:

1. with speed of mainshaft n=1250 substitution formula (7), (8), (9), calculate between this adjacent process steps main transmission system of machine tool loss of energy E during the no-load running _Uj=18840 Jiao, main transmission is restarted to rotation speed n after shutting down _jUsed time T _0j=5.32 seconds and energy consumption E _0j=1497.2 Jiao.

2. calculate energy-conservation percentage K _j: K _j=1-E _0j/ E _Uj=92%.

3. because K _jBe positive number and K _j＞K ₀(K ₀=20%), so take to shut down conservation measures, halt instruction and follow-up restart instruction are embedded in the middle of the numerical control program, the shutdown that should embed is t constantly _i=75 seconds, restarting was 135-5.23=129.77 second constantly.

3. this is shut down the check of energy conservation implementing method validity

Set up table 5 and carry out the contrast of decision process data and actual test data;

Table 5 decision process data and measured data contrast table

Contrast decision process data and actual test data have very high uniformity, thereby have verified the validity of this shutdown energy conservation implementing method.It is pointed out that because selected lathe belongs to junior machine, so the absolute value of institute's conserve energy is less.And on some heavy duty machine tools, take this shutdown energy conservation implementing method, can bring considerable energy saving benefit more.

Claims (2)

1. a Digit Control Machine Tool halt energy conservation implementing method in no-load running period of adjacent process steps is characterized in that, obtains main shaft running speed n according to processing technology before the processing _jThe determined work step interbody spacer time is obtained no-load running time T between adjacent process steps when reaching the Digit Control Machine Tool programming ₀, and pass test data table and curve fitting method are calculated and are implemented to shut down control time and the energy-conservation percentage of restarting after energy-conservation between adjacent process steps; When energy-conservation percentage is positive number, in numerical control program, embed halt instruction and follow-up restart instruction between this work step by the control time, reach the effect of saving the lathe energy.

2. Digit Control Machine Tool halt energy conservation implementing method in no-load running period of adjacent process steps according to claim 1 is characterized in that, specifically comprises the steps:

(1) establishing m is natural number, selects m level machine spindle speed, and by the real data collection, obtain two data test charts of lathe: main transmission no-load power test data table and main transmission system of machine tool under the m level speed of mainshaft start to rotation speed n from stopped status _jTransit time and the energy test tables of data that consumed;

(2) test data that step (1) is obtained carries out curve fitting, and obtains to shut down the preparation formula of energy-conservation decision-making and enforcement, i.e. main transmission loss of energy computing formula under each speed of mainshaft of lathe

Main transmission system of machine tool starts to rotation speed n from stopped status _jComputing formula transit time

And main transmission system of machine tool starts to rotation speed n from stopped status _jLoss of energy E _0jComputing formula

Wherein, A ₁, B ₁, C ₁, A ₂, B ₂, C ₂, A ₃, B ₃, C ₃The known constant that obtains for the curve match;

(3) computational methods of control time and energy-conservation percentage:

1. according to the computing formula in above-mentioned (2) step, obtain between this adjacent process steps main transmission system of machine tool energy consumption E during the no-load running _Uj, main transmission is restarted to rotation speed n after shutting down _jEnergy consumption E _0j

2. calculate energy-conservation percentage K _j=1-E _0j/ E _Uj

3. work as K _jDuring for positive number, take to shut down and restart strategy, and will comprise the halt instruction in being engraved in when shutting down and comprise according to T _0jCalculate restart the time follow-up restart instruction in being engraved in be embedded in the middle of the numerical control program.

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