CN103317150A - Method for high-accuracy turning of outer circles or inner holes of shaft-type workpieces on numerical control machine tool - Google Patents

Abstract

The invention provides a method for high-accuracy turning of outer circles or inner holes of shaft-type workpieces on a numerical control machine tool. The method includes the following steps: first finish turning, namely, using a turning tool with the feed amount of f to perform turning on the outer circles or the inner holes of the shaft-type workpieces from the end portions of the outer circles or the inner holes and along the axial direction to enable a 'tool pattern' in the shape of a single thread to be formed on the surfaces of the outer circles or the inner holes of the shaft-type workpieces; maintaining clamping states of the shaft-type workpieces and cutting parameters of the turning tool to be unchanged, sequentially performing a plurality of times of the finish turning steps, and for Nth finish turning, returning the turning tool to an initial turning position, enabling cutting points on the end portions of the outer circles or the inner holes of the shaft-type workpieces and cutting points of initial finish turning to deviate angles in odd-numbered times of equally-divided 2(N-1) within the range of 360 degrees respectively, and performing turning on the outer circles or the inner holes along the axial direction. The method can be realized only by clamping for one time on the numerical control machine tool, ordinary standard turning tools are used for accurate control and revision of processing sizes of shaft-type parts, and better surface processing quality can be acquired.

Description

The cylindrical of shaft-like workpiece or the endoporus high accuracy method for turning on Digit Control Machine Tool

Technical field

The present invention relates to the mechanical manufacturing engineering field, specifically in the high accuracy turning process on Digit Control Machine Tool, to the cylindrical of shaft-like workpiece or endoporus, owing to cutting depth and amount of feeding method of revising of " the cutter flower " of the very little one start screw type that produces all.

Background technology

When carrying out machining, no matter how sharp cutter is, also can there be circular arc R in the cutting edge cross section.In the finish turning process, very little cutting depth often easily causes the vibration of cutting edge roundness work in-process, produces " cutter relieving " phenomenon (namely usually said " cannot keeping under control " lathe tool), and the turning surface of part will produce " chatter mark ", so that workpiece is scrapped.Yet, adding man-hour in high accuracy turning, the precision of last one finish turning or even superfinishing turner order is particularly crucial, but the cutting depth ap of cutter and amount of feeding f are very little, are difficult to precisely control diameter processing dimension, do not have effective size modification method.

When the cylindrical of shaft-like workpiece or endoporus are carried out machining, lathe tool carries out turning processing to cylindrical or the endoporus of part, point of a knife contact part material, and part material produces plastic deformation, cutter cuts away excess stock, thereby produces a rule " cutter flower " at part outer or bore area.Say in theory, these " cutter flowers " are amplified certain multiple, and " cutter flower " is actually an one start screw.As shown in Figure 1, if workpiece is evenly cut open, just there are more uniform crest, trough in the surface." thread pitch " is the size of amount of feeding f, blade radius R and the point of a knife angle of wedge, determine that crest, trough height difference Rz(are the thread height) size, directly affect difference and the Surface Roughness in Turning value Ra of theoretical turning size and actual turning size.

In the precision turning processing, be accurate controlled working size, conventional method is: by improving cutting speed Vc, reduce cutting depth ap and amount of feeding f, to reduce cutting force, reduce the plastic deformation of cutting zone material, reach turning after workpiece size relatively accurate, surface roughness is effect preferably.Usually, in order to improve an accuracy class, if use the precision turning method of this routine, often need process system, the cutter that the cutting edge accuracy class is higher, the higher levels of operators such as the better lathe of rigidity to the cutting parameter exact matching, the input human and material resources are significantly increased, and manufacturing cost significantly improves.

Summary of the invention

The object of the invention is to: cylindrical or the high accuracy method for turning of endoporus on Digit Control Machine Tool that a kind of shaft-like workpiece is provided, once clamping can be finished high accuracy turning on Digit Control Machine Tool, directed main shaft angle makes workpiece surface roughness satisfy the requirement that enters next step operation to certain position.

The technical solution adopted in the present invention is:

The cylindrical of shaft-like workpiece or the endoporus high accuracy method for turning on Digit Control Machine Tool comprises following concrete steps:

At first, with described shaft-like workpiece clamping on Digit Control Machine Tool;

Initial finish turning: using cutting parameter is 0 ° as the lathe tool of cutting depth ap and amount of feeding f, directed main shaft initial angle, from cylindrical or interior bore ends, vertically the cylindrical of shaft-like workpiece or endoporus are carried out turning processing, lathe tool is in cutting, at the cylindrical of shaft-like workpiece or " the cutter flower " of an one start screw shape of bore area generation, and the pitch of cutter flower is that f, thread height are Rz;

The clamping state of maintenance shaft-like workpiece and the cutting parameter of lathe tool are constant, carry out successively the several times finish turning, adopt the crest of " the cutter flower " of the formation of dichotomy correction cylindrical or bore area, and be concrete:

The N time finish turning comprises 2 ^(N-2)Inferior vertically to the cylindrical of shaft-like workpiece or the turning operation of endoporus, wherein: during the N-1 time turning operation, with lathe tool return the turning initial position, directed main shaft angle position is 360 °/2 ^(N-1), i.e. point of a knife dislocation f/2 ^(N-1)Carry out afterwards, again turning processing, during the N-2 time turning operation, lathe tool is returned the turning initial position, directed main shaft angle position is 3 * 360 °/2 ^(N-1), i.e. point of a knife dislocation 3 * f/2 ^(N-1)Afterwards, carry out again turning processing ... N-2 ^(N-2)During inferior turning operation, with lathe tool return the turning initial position, directed main shaft angle position is (2 ^(N-1)-1) * 360 °/2 ^(N-1), i.e. point of a knife dislocation (2 ^(N-1)-1) * f/2 ^(N-1)Afterwards, carry out again turning processing.

Behind the described first time finish turning, the thread height of " cutter flower "

Then behind the N time finish turning, the crest of " cutter flower " is at cylindrical or the residual height of bore area of shaft-like workpiece $\mathrm{Rz}\left(N\right)=R-\sqrt{R^2-{\left(\frac{f}{2^{(N-1)}}\right)}^2},$

In the formula, R is blade radius,

F is the lathe tool amount of feeding;

Then behind the N time finish turning, cylindrical or the bore area diametric(al) amount of being corrected of shaft-like workpiece are: $2\×(\mathrm{Rz}-R{z}^{\′})=2\×(\sqrt{R^2-{\left(\frac{f}{2^{(N-1)}}\right)}^2}-\sqrt{R^2-{\left(\frac{f}{2}\right)}^2}).$

In described the N time finish turning, can change the cutting depth of lathe tool, reinforcement is to the correction of cylindrical or the bore area of shaft-like workpiece, the change amount of design lathe tool cutting depth is Δ x, and then cylindrical or the bore area diametric(al) amount of being corrected of shaft-like workpiece are at this moment $2\×(\sqrt{R^2-{\left(\frac{f}{2^{(N-1)}}\right)}^2}-\sqrt{R^2-{\left(\frac{f}{2}\right)}^2}+\mathrm{\Δx}).$

Described main shaft of numerical control machine tool has angle positioning function.

The beneficial effect that the present invention produces is:

The present invention is mainly used in the precision turning processing of cylindrical or the endoporus of axial workpiece in the mechanical manufacturing engineering field, once clamping can be finished on Digit Control Machine Tool, use the common standard lathe tool accurately to control, revise the processing dimension of axial workpiece, and can obtain better suface processing quality.Use the advantage of the method to have: can accurately control or revise the crest size, thereby accurately control diameter dimension; What is more important, the method is accurately revised (control) X-direction (diametric(al)) finishing size by changing the Z-direction coordinate dimension, and can carry out μ m level cutting output processing (concrete value processing is relevant with actual nose radius, linear velocity Vc, feeding f, part material etc.).Also can greatly reduce simultaneously Rz, Ra equivalent, thereby reduce the Part Surface Roughness value, improve suface processing quality.

In the processing of elongate rod finish turning, generally adopt the glaive tool to carry out turning in addition, resistance to cutting is large, easily makes the workpiece vibration-generating.But the Application standard lathe tool carries out " dislocation method " processing, can greatly reduce the possibility that this situation occurs, thereby improves crudy.

According to shown in the table one, after the first time, turning was finished, adopt secondary turning, machine away each crest of piece surface, then can revise a certain amount of size of turning, and can obtain better suface processing quality.Use the method can carry out the correction processing of μ m level, thereby accurately control the diameter processing dimension of axial workpiece; In actual the use, actual measurement size and theory are consistent.

In sum, use cylindrical or the high accuracy method for turning of endoporus on Digit Control Machine Tool of shaft-like workpiece of the present invention, can obtain following effect:

(1) the axial workpiece cylindrical of turning or diameter of bore size can reach μ m class precision;

(2) can reduce the surface roughness value of part, obtain better part machined surface quality;

(3) the method easily realizes, applicability is wide.

Description of drawings

The structural representation of radial section when Fig. 1 is turning workpiece excircle;

Fig. 2 is that for the first time turning processing is rear, the schematic diagram of the surperficial remaining allowance height Rz of excircle of workpiece;

Fig. 3 is that for the second time turning processing is rear, the schematic diagram of the surperficial remaining allowance height Rz ' of excircle of workpiece;

Fig. 4 is that for the first time turning adds man-hour, 0 ° of machining sketch chart of benchmark main shaft orientation;

Fig. 5 is that for the second time turning adds man-hour, the benchmark main shaft orientation redirect to 180 ° of machining sketch charts;

The specific embodiment

Shown in Fig. 2～5, the present invention is a kind of cylindrical or the high accuracy method for turning of endoporus on Digit Control Machine Tool of shaft-like workpiece, comprises following concrete steps:

At first, with described shaft-like workpiece clamping on Digit Control Machine Tool; In this specific embodiment, the main shaft of Digit Control Machine Tool has angle positioning function.The present invention also can use at the Digit Control Machine Tool that does not have the main shaft angle positioning function, and adopt manually auxiliary positioning this moment, can realize equally the high-precision method for turning of this kind.

Initial finish turning: use cutting parameter to be the lathe tool of cutting depth ap and amount of feeding f, directed main shaft initial angle position is 0 °, from cylindrical or interior bore ends, vertically the cylindrical of shaft-like workpiece or endoporus are carried out turning processing, lathe tool is in cutting, at the cylindrical of shaft-like workpiece or " the cutter flower " of an one start screw shape of bore area generation, and the pitch of cutter flower is that f, thread height are Rz;

At this moment, the thread height of " cutter flower " For the first time behind the finish turning namely, shaft-like workpiece cylindrical or the diameter of bore direction maximum that remains to be revised is

In the formula, R is blade radius,

F is the lathe tool amount of feeding.

The clamping state of maintenance shaft-like workpiece and the cutting parameter of lathe tool are constant, directed main spindle's is to certain angle, successively vertically to foreign round or endoporus carry out the finish turning step of several times, adopt the crest of " cutter flower " that dichotomy correction cylindrical or bore area form, concrete:

The N time finish turning: lathe tool is returned the turning initial position, lathe tool o'clock is departed from respectively in 360 ° of scopes successively in the feed of the feed point of the cylindrical of shaft-like workpiece or interior bore ends and initial finish turning divide equally 2 ^(N-1)The angle of odd number time, i.e. point of a knife dislocation f/2 ^(N-1), vertically to foreign round or endoporus carry out turning processing.Comprise 2 in the N time finish turning ^(N-2)Inferior vertically to the cylindrical of shaft-like workpiece or the turning operation of endoporus, wherein:

During the N-1 time turning operation, lathe tool is returned the turning initial position, directed main shaft angle position is 360 °/2 ^(N-1)Even lathe tool departs from 360 °/2 at the feed point of the feed point of the cylindrical of shaft-like workpiece or interior bore ends and initial finish turning ^(N-1)Angle, point of a knife dislocation f/2 ^(N-1)After, lathe tool more vertically to foreign round or endoporus carry out turning processing;

During the N-2 time turning operation, lathe tool is returned the turning initial position, directed main shaft angle position is 3 * 360 °/2 ^(N-1)Even lathe tool departs from 3 * 360 °/2 at the feed point of the feed point of the cylindrical of shaft-like workpiece or interior bore ends and initial finish turning ^(N-1), point of a knife dislocation 3 * f/2 ^(N-1)After, lathe tool more vertically to foreign round or endoporus carry out turning processing;

……

N-2 ^(N-2)During inferior turning operation, lathe tool is returned the turning initial position, directed main shaft angle position is (2 ^(N-1)-1) * 360 °/2 ^(N-1)Even lathe tool departs from (2 at the feed point of the feed point of the cylindrical of shaft-like workpiece or interior bore ends and initial finish turning ^(N-1)-1) * 360 °/2 ^(N-1)Angle, point of a knife dislocation (2 ^(N-1)-1) * f/2 ^(N-1)After, lathe tool more vertically to foreign round or endoporus carry out turning processing.

At this moment, " cutter flower " is at cylindrical or the residual height of bore area of shaft-like workpiece

Namely behind the N time finish turning, shaft-like workpiece cylindrical or the diameter of bore direction maximum that remains to be revised is

In the formula, R is blade radius,

F is the lathe tool amount of feeding;

Then behind the N time finish turning, cylindrical or the bore area diametric(al) amount of being corrected of shaft-like workpiece are: $2\×(\mathrm{Rz}-R{z}^{\′})=2\×(\sqrt{R^2-{\left(\frac{f}{2^{(N-1)}}\right)}^2}-\sqrt{R^2-{\left(\frac{f}{2}\right)}^2}).$

In the N time finish turning, can change the cutting depth of lathe tool, strengthen the correction to cylindrical or the bore area of shaft-like workpiece, the change amount of design lathe tool cutting depth is Δ x, then this moment shaft-like workpiece cylindrical or the bore area diametric(al) amount of being corrected be $2\×(\sqrt{R^2-{\left(\frac{f}{2^{(N-1)}}\right)}^2}-\sqrt{R^2-{\left(\frac{f}{2}\right)}^2}+\mathrm{\Δx}).$

As previously mentioned, want turning diameter of axle size precisely controlled, then need the corrugation pitch of accurate Control Shaft class Central of the parts line both sides, accurately revise in other words corrugation pitch between the both sides; Want to get better turning surface quality, then need to reduce crest as far as possible, trough pitch difference Rz(is the thread height) value is big or small, as shown in Figure 2.Owing to exist (being that the f value is non-vanishing) of feed value f, cutting tips (blade radius is R) will stay the residual quantity that theoretical level is Rz at surface of the work.Key of the present invention is exactly the method that reduces the Rz value, realizes accurately controlling diameter dimension by twice above Cutting trajectory of reasonable setting, and specific implementation method is as described below.

The below specifies to adopt the method for twice turning fine finishining (N=2):

On the basis of for the first time cutting, for the second time cutting is carried out machining for the crest that stays for the first time specially, in order to reach point of a knife dislocation " f/2 " purpose, on the turning initial position, feed point must be in the 180 ° directions of feed first time spot projection to the part end face for the second time.

As shown in Figure 3, for the second time cutting position makes nose radius central alignment crest center line just at f/2 place at directions X (cylindrical or bore area diametric(al)), can realize removal amount Rz, at diametric(al) realization removal amount 2* (Rz-Rz '), namely Thereby accurately control or correction crest size μ m level cutting output processing (concrete value processing is relevant with actual nose radius, linear velocity Vc, feeding f, part material etc.) is to reach the purpose of accurate control diameter dimension.

In Fig. 3, $\mathrm{Rz}=R-\sqrt{R^2-{\left(\frac{f}{2}\right)}^2};$ $R{z}^{\′}=R-\sqrt{R^2-{\left(\frac{f}{4}\right)}^2}$

Further, if need larger correction.Take the method as the basis, by calculating in advance, change simultaneously a certain amount of X-direction coordinate dimension Δ x, on diametric(al), can realize removal amount 2* (Rz-Rz '+Δ x), namely $2*(\sqrt{R^2-{\left(\frac{f}{4}\right)}^2}-\sqrt{R^2-{\left(\frac{f}{2}\right)}^2}+\mathrm{\Δx}),$ To reach the purpose of accurate control Finishing Parts Machining size.

Adopt above method to reduce Rz, Ra equivalent, reduce Part Surface Roughness, thereby improve suface processing quality.

With the standard vehicle blade of tool arc R0.8, R0.4, cutting parameter commonly used is example, from calculate following direct correction tables of data by Fig. 3:

Table one:

In addition, according to Rz, Ra definition rule difference, actual Rz value and theory are more approaching; Ra is then without direct rule, but can reflect certain corresponding trend from Rz.

The below illustrates that again take the Siemens840D numerically-controlled machine tool system as example the present invention carries out the method for high accuracy turning at the outer round surface of shaft-like workpiece:

As shown in Figure 4: at for the first time processing, 0 ° of benchmark main shaft orientation;

The Prog1 main body:

……

M03 Ss Ff;

G01 ZL;

G01 XR; Point of a knife is moved to ready position

M05; Above best single hop is carried out, and treats that main shaft stops fully

SPCON; Speed is controlled transitions to angle control

SPOS=0;

SPCOF;

G01 Z-n M03 Ss Ff;

G01 X (R+5); Return to home

M30;

As shown in Figure 5: in secondary operations, the benchmark main shaft orientation redirect to 180 °;

The Prog2 main body:

……

M03 Ss Ff;

G01 ZL;

G01 XR; Point of a knife is moved to ready position

M05; Above best single hop is carried out, and treats that main shaft stops fully

SPCON; Speed is controlled transitions to angle control

SPOS=180;

SPCOF;

SPCOF;

G01 Z-n M03 Ss Ff;

G01 X (R+5); Return to home

M30;

If to adopting this method to carry out the cylindrical of shaft-like workpiece of high accuracy turning or the surface roughness of endoporus has higher requirement, can also be by processing request and the parameter of above-mentioned the N time finish turning, to foreign round or the surperficial surplus of endoporus proceed progressively to process.For the third time during finish turning: adopt 2 turning operations to finish, during 2 turning operations, directed main spindle's, lathe tool departs from respectively 90 ° and 270 ° at the feed point of the feed point of the cylindrical of shaft-like workpiece or interior bore ends and initial finish turning, i.e. misplace f/4 and 3f/4 of point of a knife; During No. the 4th finish turning: adopt 4 turning operations to finish, during 4 turning operations, directed main spindle's, lathe tool departs from respectively 45 °, 135 °, 225 ° and 315 ° at the feed point of the feed point of the cylindrical of shaft-like workpiece or interior bore ends and initial finish turning, i.e. misplace f/8,3f/8,5f/8 and 7f/8 of point of a knife.Proceed turning operation by this requirement, this specification describes in detail no longer one by one.

In theory, the inventive method also can simply be transplanted on the machine tool and process, and N the finish turning that only needs the dislocation of control point of a knife to carry out successively dichotomy just can be realized.But because on the machine tool, the point of a knife magnitude of misalignment can not control by the method for control main shaft angle position, the feed position is to regulate by the reference axis numerical value of cutter, this adjusting is subjected to cutter to regulate the restriction of scale (precision).Therefore, when adopting machine tool cutting " tartar " crest, can not accurately control position, the accurate controlling dimension of cutting crest, the size of turning is unordered with uncontrollable, can not satisfy high-precision requirement with the cylindrical of machine tool working shaft-like workpiece or the surface roughness of endoporus.

Claims (4)

1. the cylindrical of shaft-like workpiece or the endoporus high accuracy method for turning on Digit Control Machine Tool is characterized in that, comprises following concrete steps:

At first, with described shaft-like workpiece clamping on Digit Control Machine Tool;

Initial finish turning: using cutting parameter is 0 ° as the lathe tool of cutting depth ap and amount of feeding f, directed main shaft initial angle, from cylindrical or interior bore ends, vertically the cylindrical of shaft-like workpiece or endoporus are carried out turning processing, lathe tool is in cutting, at the cylindrical of shaft-like workpiece or " the cutter flower " of an one start screw shape of bore area generation, and the pitch of cutter flower is that f, thread height are Rz;

The clamping state of maintenance shaft-like workpiece and the cutting parameter of lathe tool are constant, carry out successively the several times finish turning, adopt the crest of " the cutter flower " of the formation of dichotomy correction cylindrical or bore area, and be concrete:

The N time finish turning comprises 2 ^(N-2)Inferior vertically to the cylindrical of shaft-like workpiece or the turning operation of endoporus, wherein: during the N-1 time turning operation, with lathe tool return the turning initial position, directed main shaft angle position is 360 °/2 ^(N-1), i.e. point of a knife dislocation f/2 ^(N-1)Carry out afterwards, again turning processing, during the N-2 time turning operation, lathe tool is returned the turning initial position, directed main shaft angle position is 3 * 360 °/2 ^(N-1), i.e. point of a knife dislocation 3 * f/1 ^(N-1)Afterwards, carry out again turning processing ... N-2 ^(N-2)During inferior turning operation, with lathe tool return the turning initial position, directed main shaft angle position is (2 ^(N-1)-1) * 360 °/2 ^(N-1), i.e. point of a knife dislocation (2 ^(N-1)-1) * f/2 ^(N-1)Afterwards, carry out again turning processing.

2. the cylindrical of shaft-like workpiece according to claim 1 or the endoporus high accuracy method for turning on Digit Control Machine Tool is characterized in that, behind the described first time finish turning, the thread height of " cutter flower "

Then behind the N time finish turning, the crest of " cutter flower " is at cylindrical or the residual height of bore area of shaft-like workpiece $\mathrm{Rz}\left(N\right)=R-\sqrt{R^2-{\left(\frac{f}{2^{(N-1)}}\right)}^2},$

In the formula, R is blade radius,

F is the lathe tool amount of feeding;

Then behind the N time finish turning, cylindrical or the bore area diametric(al) amount of being corrected of shaft-like workpiece are: $2\×(\mathrm{Rz}-R{z}^{\′})=2\×(\sqrt{R^2-{\left(\frac{f}{2^{(N-1)}}\right)}^2}-\sqrt{R^2-{\left(\frac{f}{2}\right)}^2}).$

3. the high accuracy method for turning of the cylindrical of shaft-like workpiece according to claim 2 or endoporus, it is characterized in that, in described the N time finish turning, can change the cutting depth of lathe tool, reinforcement is to the correction of cylindrical or the bore area of shaft-like workpiece, the change amount of design lathe tool cutting depth is Δ x, and then cylindrical or the bore area diametric(al) amount of being corrected of shaft-like workpiece are at this moment $2\×(\sqrt{R^2-{\left(\frac{f}{2^{(N-1)}}\right)}^2}-\sqrt{R^2-{\left(\frac{f}{2}\right)}^2}+\mathrm{\Δx}).$

4. the cylindrical of shaft-like workpiece according to claim 1 or the endoporus high accuracy method for turning on Digit Control Machine Tool is characterized in that, described main shaft of numerical control machine tool has angle positioning function.

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