Summary of the invention
For overcoming above-mentioned defective, technical problem to be solved by this invention provides a kind of rigidity and better is difficult for higher microbit of the breaking of rod and position, hole precision and the method for processing this microbit.
The objective of the invention is to be achieved through the following technical solutions:
A kind of microbit comprises apex point and bores body that described apex point comprises plural cutting edge; Described brill body is provided with the spiralling chip pocket more than two, wherein, described chip pocket comprises at least one long chip pocket and at least one short chip pocket, and described long chip pocket extends to brill body end from the position of apex point, and described short chip pocket only is arranged on the leading portion that bores body; Short chip pocket is different with the helical angle of long chip pocket, and both change to converging state by released state; Described short chip pocket ends in itself and the intersection of long chip pocket.
Described apex point comprises two main cutting edges along little auger spindle heart symmetry, two operator faces, two auxilliary knife faces.Since the part of the apex point of microbit still with the same complete symmetry of microbit of routine, make apex point stress balance when little drilling is cut, avoided because of the monolateral force unbalance that is subjected to of the apex point of wall scroll cutting edge, the radial load of deriving, and then influence position, hole precision, influence the thick defective in hole; And cutting edge drill bit with respect to single-blade, such design makes the cutting edge abrasion resistance properties improve greatly, under identical cutting output and cutting speed situation, article two, cutting edge goes to share the cutting output of a cutting edge originally, the amount of feeding of every cutting edge is equivalent to half of wall scroll sword, more wear-resistant, and then the hole is slightly better relatively, the processing life-span is also longer.
The helical angle of an end that is close to the termination place of the short chip pocket of described microbit is greater than the helical angle of long chip pocket.Select that bigger chip pocket of helical angle as short chip pocket, can better guarantee the chip removal effect of whole microbit.This design is particularly useful for processing the microbit of the sheet material of some more difficult dust discharges.
Described short chip pocket comprises: be arranged on the helical angle helical angle same angle part the same with long chip pocket near apex point part one end, reach the helical angle augmenting portion that increases gradually with helical angle that helical angle is connected with angle part.
The helical angle of described short chip pocket is equal to the axial length of angle part or greater than the length of apex point major part part; Wherein, described major part is meant partly that in microbit it bores the big part of external diameter of body than postmedian at the external diameter of the front end of apex point part.Such design is aimed at the major part brill.The helical angle of short chip pocket enters the helical angle augmenting portion with angle part again after exceeding the major part part, such design has guaranteed that all structures of major part part all are symmetrical, and good balance effect has further improved position, the hole precision that adds man-hour.
Described short chip pocket also comprises and being arranged on behind the helical angle augmenting portion, is the large helix angle constant portion at constant helical angle with the helical angle of the maximum of helical angle augmenting portion.Such design makes the helical angle augmenting portion can become the transitional region that helical angle increases, and short chip pocket ends in itself and the intersection of long chip pocket with a constant bigger helical angle.
The groove depth of the helical angle augmenting portion of described short chip pocket shoals gradually, and the groove depth of the short chip pocket of described intersection is shallower than the groove depth of the long chip pocket at co-located place.Such design, making has significantly line of demarcation between the long chip pocket of intersection and the short chip pocket.Such design is owing to the groove width meeting broad in intersection, and certain influence can be arranged the rigidity of microbit; And the groove depth of long chip pocket need have certain degree of depth because chip removal, and short chip pocket then can appropriateness shoal, and shoaling with the degree of depth remedies the broaden loss of the rigidity brought of groove width.
The length of described short chip pocket account for long chip pocket length 3%~50%.Such design, short chip pocket can be dissolved in the long chip pocket faster, and the chip pocket of the back segment of microbit reduces obviously, brings the lifting on the rigidity also comparatively obvious.
The length of described short chip pocket account for long chip pocket length 65%~90%.Such design, relatively be applicable in boring and slightly had relatively high expectations in the hole, perhaps the dirt of certain sheet material bits belong to the difficult type of discharging, low such as vitrification point, the dirt bits easily are in melting state etc., need the dust discharge space enough, promptly need the dust discharge simultaneously of two grooves, and the flute length of little brill is longer, adds the situation of the easy root breaking of rod in man-hour.For such microbit, its short chip pocket helical angle can slowly increase, the rigidity that converges the meet that is forwardly brought the position until crossing with long chip pocket in default position, having reduced descends, the problem of the easy breaking of rod; In addition, owing to add jumping chisel having relatively high expectations to rigidity, become single groove dust discharge in the not enough partial design of elongated rigid, strengthened the rigid nature of elongated portion, and because the time of the boring of elongated portion is very short, dust-exhausting quantity itself is just smaller, therefore can't influence the performance of chip removal, solve the former microbit lengthening rigidity problem of the easy breaking of rod inadequately, be highly suitable for adding the processing of jumping chisel.
A kind of method of processing above-mentioned microbit may further comprise the steps:
A: on bar, process chip pocket;
B: the normal mill back of the body and sharpening processing;
Wherein, in the described steps A, the step of processing chip pocket comprises:
A1: add section chief's chip pocket;
A2: process the short chip pocket different with the helical angle of long chip pocket; Make short chip pocket end in itself and the intersection of long chip pocket.
In the described steps A 1, described bar rotation by the chuck clamping, and slotted wheel grinds long chip pocket according to the grinding of conventional bit fluting program;
In the described steps A 2, bar is under the chuck clamping, the elongated slot start angle carries out 180 degree rotations relatively, slotted wheel strengthens with relative elongated slot helical angle, shorten slotting length, and changing the emery wheel height, the another set of fluting program that the tail end degree of depth of feasible short chip pocket shoals is gradually finished the processing of short chip pocket.
The present invention makes long chip pocket different with the helical angle of short chip pocket, and has at least two grooves to converge in certain distance because the brill chip pocket more than two on one's body of microbit is set at least one long chip pocket and at least one short chip pocket; And make short chip pocket end in itself and the intersection of long chip pocket; Therefore, the cutting swarf of the pairing cutting edge cutting of short chip pocket can be discharged by long chip pocket by intersection by short chip pocket earlier again, realizes necessary chip removal.And since short chip pocket terminate before, make the rigid body portion of cell body increase, the thick increase of core, little brill rigidity is better, makes that position, hole performance is good, breaking of rod performance better, the life-span lengthening, overall performance is promoted.
The specific embodiment
The invention will be further described below in conjunction with accompanying drawing and preferred embodiment.
Technical solutions according to the invention are applicable to the microbit more than the twolip, below be that example describes just with the microbit of the twolip double flute of diameter below 6.5mm.
The structure of the microbit of described twolip double flute is shown in Fig. 5-11, comprise apex point 41 and bore body 42, described apex point 41 comprises two main cutting edges along little auger spindle heart symmetry, two operator faces, two auxilliary knife face (not shown)s, and structure is same as conventional little brill; Described brill body 42 is provided with two spiralling chip pockets (44,45).The spiralling chip pocket of described brill body is two, comprises a long chip pocket 44 and a short chip pocket 45, and long chip pocket 44 is different with the helical angle of short chip pocket 45; Described short chip pocket 45 ends in itself and the intersection of long chip pocket 44.At close apex point place, chip removal is finished jointly by two chip pockets, after converging, is independently finished by long chip pocket 44.Wherein, described helical angle is meant on one's body boring, the tangent line of circular helix with pass through folded sharp angle between the face of cylinder straight edge line at point of contact.
Described long chip pocket 44 extends to brill body 42 ends from the position of apex point 41, and its helical angle is invariable; Described short chip pocket 45 only is arranged on the leading portion that bores body, and the helical angle of the part that is close to the termination place of the short chip pocket 45 of microbit is greater than the helical angle of long chip pocket 44.Because the helical angle of described short chip pocket 45 is bigger than long chip pocket 44, short chip pocket 45 can be crossing with long chip pocket 44 in than short distance, and two chip pockets converge, and lack chip pocket 45 and so far finish.
Select that bigger chip pocket of helical angle as short chip pocket 45, can better guarantee the chip removal effect of whole microbit.If the helical angle of our long chip pocket of drill bit is 45 degree, promptly dust discharge is smoothly when 45 spend, if will lack the helical angle of chip pocket so is provided with greatlyyer, the big more then dust discharge of helical angle component is big more, the dust discharge ability is just good more, and short chip pocket just can not influence the dust discharge effect of long chip pocket and whole microbit; And if the helical angle of short chip pocket less than the helical angle of long chip pocket, if problem has appearred in the dust discharge of short chip pocket, blocks in the short chip pocket, even the dust discharge of long chip pocket is very smooth and easy, the dust discharge of whole microbit also can be smooth and easy inadequately.This design especially is fit to some microbits that are used to process the sheet material of more difficult dust discharge.
Wherein, the length of described short chip pocket 45 account for long chip pocket 44 length 3%~50%.Can be 5% or 10% length of long chip pocket as, described short chip pocket, the angular range of the helical angle of described long chip pocket 44 can select 20 to spend between 50 degree; Described short chip pocket 45 can big again 5 than the angle of the helical angle of long chip pocket 44 be spent to about 40 degree.Such design, short chip pocket can be dissolved in the long chip pocket faster, and the chip pocket of the back segment of microbit reduces obviously, brings the lifting on the rigidity also comparatively obvious.
Also can be with the Design of length of short chip pocket account for long chip pocket length 65%~90%.The so design of long short chip pocket, relatively be applicable in boring and slightly had relatively high expectations in the hole, perhaps the dirt of certain sheet material bits belong to the difficult type of discharging, low such as vitrification point, the dirt bits easily are in melting state etc., need the dust discharge space enough, promptly need the dust discharge simultaneously of two grooves, and the flute length of little brill is longer, adds the situation of the easy root breaking of rod in man-hour.For such microbit, its short chip pocket helical angle can slowly increase, the rigidity that converges the meet that is forwardly brought the position until crossing with long chip pocket in default position, having reduced descends, the problem of the easy breaking of rod; In addition, owing to add jumping chisel having relatively high expectations to rigidity, become single groove dust discharge in the not enough partial design of elongated rigid, strengthened the rigid nature of elongated portion, and because the time of the boring of elongated portion is very short, dust-exhausting quantity itself is just smaller, therefore can't influence the performance of chip removal, solve the former microbit lengthening rigidity problem of the easy breaking of rod inadequately, be highly suitable for adding the processing of jumping chisel.
Please in conjunction with the accompanying drawings 6 and accompanying drawing 8-11: shown in Fig. 8 is in the major part part, also is in the long chip pocket and the short chip pocket in symmetry stage, the helical angle of long chip pocket herein and weak point chip pocket, and core is thick all equally; Shown in Fig. 9 and Figure 10 is the position that long chip pocket and short chip pocket begin to cross, the groove depth of the helical angle augmenting portion of described short chip pocket shoals gradually, the groove depth of the short chip pocket of described intersection is shallower than the groove depth of the long chip pocket at co-located place, long chip pocket herein and short chip pocket have begun asymmetric, short chip pocket helical angle has strengthened much, and the degree of depth of lacking chip pocket is shallow than long chip pocket also; The relative conventional bit of a long chip pocket groove wherein is darker wideer, and the chip space of chip pocket can do more; Shown in Figure 11 is that short chip pocket converges to the position in the long chip pocket fully, has only long chip pocket herein, dotted line is represented be short chip pocket should the position.Such design, making has significantly line of demarcation between the long chip pocket of intersection and the short chip pocket.Such design is owing to the groove width meeting broad in intersection, almost is equivalent to the twice groove width, and certain influence can be arranged the rigidity of microbit; And the groove depth of long chip pocket need have certain degree of depth because chip removal, and short chip pocket then can appropriateness shoal, and shoaling with the degree of depth remedies the broaden loss of the rigidity brought of groove width.And, such design, still short chip pocket can well converge with between the long chip pocket.Groove width at meet is less, and meet is just more level and smooth, is easier to processing.
Described short chip pocket can comprise that helical angle is with angle part and helical angle augmenting portion two parts.Be arranged near being the same angle part of helical angle in the segment limit of apex point one end, its helical angle is identical with long chip pocket helical angle; In the segment limit near the unification end that intersects is the helical angle augmenting portion that is connected with angle part with helical angle, and its helical angle increases gradually, in the long chip pocket that crosses.
The helical angle of described short chip pocket 45 is equal to the axial length of angle part or greater than the length of apex point major part part 43.The helical angle of short chip pocket 45 enters the helical angle augmenting portion again with angle part after exceeding major part part 43.Wherein, described major part part 43 is meant that in microbit it is in the big part of external diameter that the external diameter of the front end of apex point part bores body than postmedian, and about 0.5mm is long to 1mm, it has only the bigger major part part 43 of external diameter to contact with workpiece to be processed when drilling.Need surpass major part part 43 with long chip pocket 44 with the part of helical angle, such design has guaranteed that all structures of major part part 43 all are symmetrical, the power that its two back ofs the body and hole wall friction are subjected to also is that symmetry is impartial, and good balance effect has further improved position, the hole precision that adds man-hour.Certainly, the helical angle of described short chip pocket 45 also can be less than the length of apex point major part part 43 with the axial length of angle part, but such design its in process, the effect of its balance just is equal to the axial length of angle part not as the helical angle of short chip pocket 45 or greater than the microbit of the length of apex point major part part 43, position, hole precision is poor slightly naturally, and unbalanced like this drill bit is after the cutting of long period, can wear and tear gradually in the back of major part part, and the degree varies of both sides wearing and tearing, just more uneven.
Said structure bores for major part and non-major part brill all can be suitable for.Bore for non-major part, near in apex point one segment distance, preferably in 0.3mm, apex point part and two chip pockets are symmetrical arranged, then bore stress balance down, the effect of its position, hole precision is also better; Grinding off under a part of apex point situation when grinding and also can guarantee to turn over simultaneously, two chip pockets in product apex point place behind the sharpening and two cutting edges are still symmetrical.
Described chip pocket can also be designed to comprise three parts of the same angle part of helical angle, helical angle augmenting portion and large helix angle constant portion.Be arranged near being the same angle part of helical angle in the segment limit of apex point one end, its helical angle is identical with long chip pocket 44 helical angles; Near being the large helix angle constant portion that is the constant helical angle with a helical angle in the segment limit of the unification end of intersecting much larger than long chip pocket 44 helical angles; Helical angle is with the helical angle augmenting portion that increases gradually for helical angle between angle part and the large helix angle constant portion, as middle transition.Wherein, described large helix angle constant portion can be the constant helical angle with the helical angle of the maximum of helical angle augmenting portion.Such design makes the helical angle augmenting portion become the transitional region that helical angle increases, and short chip pocket 45 ends in itself and the intersection of long chip pocket 44 with a constant bigger helical angle.The helical angle of helical angle augmenting portion can be constant increase, also can be non-constant increase, the front and back gradual change; And the concrete distribution of the same angle part of helical angle, helical angle augmenting portion and large helix angle constant portion, can be according to the sheet material that will process and specific design.
And for the sheet material of some easy dust discharges, the microbit of its use also can be designed to the helical angle of short chip pocket the helical angle less than long chip pocket.Though such design can cause the bottleneck of chip removal at short chip pocket, its dust discharge effect is not as selecting that bigger chip pocket of helical angle as short chip pocket, under the prerequisite that does not influence the dust discharge effect, can so that microbit has better rigidity.
(1.6mm is thick with the plate of beneficial S1141 that item number is made a living below, 6 layers of copper, every layer of 1OZ, two boards is one folded) be sheet material to be processed, microbit of the present invention and conventional little brill are done the contrast test of machining accuracy, and position, the hole precision with the lower plate of two boards in the test is position, the hole CPK value of being got in the test:
Wherein, the little brill of described routine is traditional little brill structure, and it has two symmetrical cutting edges, two chip pockets, and helical angle is got 42 degree, and micro-drill diameter is 0.25mm, and flute length 4.5mm, core diameter account for external diameter 70%;
Adopted in the embodiment of the invention little brill for having two symmetrical cutting edges, have two chip pockets, a long chip pocket, helical angle be 45 the degree, flute length is 4.5mm; Article one, lack chip pocket, helical angle is spent to 75 degree from 45 and is changed, and flute length is 2.0mm, and short chip pocket converges in beginning of 1.2mm place and long chip pocket, in the 2.0mm place terminates long chip pocket; Its core diameter accounts for external diameter 70%.
Its borehole conditions is: rotating speed 150KRPM (150,000 rpms); Running speed 40mm/s; 2000 holes are limit in the hole.
Position, the hole CPK Value Data of contrast test is as shown in following table 1:
Table 1:
As can be seen, the embodiment of the invention is better than position, the hole precision of conventional bit from last table and Figure 12, especially at the boring number 1000 when above, position, hole precision obviously is better than conventional bit.
Process the method that microbit of the present invention adopts, can may further comprise the steps:
S1. add section chief's chip pocket: bar rotation by the chuck clamping, and slotted wheel grinds long chip pocket according to the grinding of conventional bit fluting program;
S2. process short chip pocket: after the elongated slot grinding is good, bar is under the chuck clamping, carry out 180 degree rotations (elongated slot start angle relatively), (the elongated slot helical angle strengthens slotted wheel relatively with another set of fluting program, shorten slotting length, and change the emery wheel height, make the tail end degree of depth of short chip pocket shoal gradually, shown in Fig. 8-11), finish the processing of short chip pocket;
S3. mill is carried on the back: method, process and the conventional bit of the mill back of the body are the same, take turns according to setting the running orbit grinding with the mill floor sand, and two mill back ofs the body are finished by twice grinding of one group of emery wheel, and process is identical;
S4. sharpening: the procedure of sharpening is also all the same with traditional conventional bit, delivers to the sharpening station at bar, according to angle corresponding relation between slot grinding and the sharpening, the bar start angle is adjusted in the chuck rotation, the grinding that moves horizontally of sharpening emery wheel group then grinds an operator face, a secondary knife face, after finishing, chuck clamping bar Rotate 180 degree, the sharpening emery wheel repeats above-mentioned motion, the grinding another side, after the both sides sharpening was finished, this drill bit was just produced and is finished.
The structure of above-mentioned two kinds of short chip pockets can specifically be selected design according to the material of the size of microbit and the workpiece that will process: the helical angle that designs long chip pocket as the case may be, and the angle of the maximum helix angle of short chip pocket after, its short chip pocket is the initial fluting that begins with the helical angle of long chip pocket, helical angle constant through after the major part part, it is big that the control helical angle becomes rapidly, until the angle of the maximum helix angle of the short chip pocket that reaches setting.After short chip pocket arrived maximum helix angle, can design as the case may be was directly to cross in long chip pocket, and still continuing with current maximum helix angle is that the lasting segment distance in constant helical angle crosses in long chip pocket again.
Certainly, as long as short chip pocket can cross in long chip pocket, after helical angle was with angle part, how the helical angle of short chip pocket changes can be realized the present invention, only needed can import in the long chip pocket to get final product.If shorten the length of short chip pocket as far as possible, just adjust machine, strengthen the angle of the helical angle of short chip pocket as far as possible; If desired than long short chip pocket, just reduce the angle of the helical angle of short chip pocket, the length of the part of perhaps extend front end and elongated slot helical angle equal angular (symmetric part that promptly extends is moved after the part that helical angle changes) gets final product.
Described short chip pocket is long more, and it is just good more that it holds the dirt effect, and is also just many more to the sacrifice of position, hole precision; Otherwise the control to position, hole precision is good more, and its effect of holding dirt is just poor more.Slightly better when the needs hole, and when not too high, just can adopt the long microbit of short chip pocket to the requirement of position, hole precision; When adding, some material need man-hour position, hole precision fine, and require to the hole is thick that lower (criterion and roughness standards that the hole is thick are similar, be that numerical value is the smaller the better) or the dirt of sheet material bits when being easy to discharge, as some harder sheet material, the microbit that just can adopt short chip pocket to lack slightly.
The present invention makes long chip pocket different with the helical angle of short chip pocket because the brill chip pocket more than two on one's body of microbit is set at least one long chip pocket and at least one short chip pocket; And have at least two grooves in certain distance, to converge; Short chip pocket ends in itself and the intersection of long chip pocket; Therefore, the cutting swarf of the pairing cutting edge cutting of short chip pocket can be discharged by long chip pocket by intersection by short chip pocket earlier again, realizes necessary chip removal.And since short chip pocket terminate before, make the rigid body portion of cell body increase, the thick increase of core, little brill rigidity is better, makes that position, hole performance is good, breaking of rod performance better, the life-span lengthening, overall performance is promoted.
And on the basis of single groove chip removal,, therefore can further increase the groove depth of this long chip pocket because the core of the cell body of long chip pocket part is thick bigger, strengthened the chip removal ability of this long chip pocket.Little brill like this adds man-hour and the hole wall friction is little, position, hole precision height, life-span is longer, this structure little brill that is particularly suitable for extending, can well remedy because position, hole, breaking of rod performance decrease and the disappearance that drill bit length lengthening brings makes these performances that add jumping chisel not be worse than the performance of conventional length drill bit.
In addition, microbit compared to single-blade list groove, because still the microbit with routine is the same for the part of the apex point of microbit of the present invention, its two cutting edges, two main back knife faces, two auxilliary back knife faces, all along the axle center symmetry, and short chip pocket and elongated slot converge, and really play the dust discharge effect, make:
(1) aspect, position, hole is better:
This is because the cutting edge of the microbit of single-blade list groove is a wall scroll, and apex point bores down and is subjected to force unbalance, can derive radial load, influences the position, hole; And the apex point of microbit of the present invention is symmetrical, does not have imbalance problem, and under identical situation about promoting because of position, wall scroll groove hole, position, the hole performance of microbit of the present invention is better.
(2) thick aspect, hole is better:
This is because two cutting edge cutting outputs are little, cut smooth and easyly, and the dirt bits are more broken thin, are easy to discharge, and the hole is slightly good; There is not radial load in the apex point stress equalization, and it is thick can not to destroy the hole.
(3) abrasion resistance properties is good:
This is that abrasion resistance properties significantly improves, and then the life-span is longer, the hole is slightly better because the cutting output of wall scroll sword is born by two cutting edges, and the amount of feeding of microbit of the present invention reduces by half.
(4) auxiliary facilities such as production, use need not made change, and applicability is strong:
Microbit of the present invention only spiral fluted helical angle and length has been done adjustment, and processing is got up uncomplicated; And in use fully routinely drill bit technology use, such as the sharpening operation etc., need not do any adjustment.And with respect to the single-blade single flute drill, just do not possess such advantage, and need more complicated statement to control the processing of a plurality of auxilliary blades during production, quality inspection, turn over mill etc. and all need the change standard, also need carry out corresponding change in use.
Above content be in conjunction with concrete preferred implementation to further describing that the present invention did, can not assert that concrete enforcement of the present invention is confined to these explanations.Such as, the above microbit of three swords also is to be suitable for technical solutions according to the invention, microbit as three sword three-flutes, its three pairing chip pockets of cutting edge are set to two short chip pockets of a long chip pocket, two short chip pockets cross respectively in long chip pocket, and end in the intersection of long chip pocket, also can well realize improving the effect of the rigid nature of equal microbit.For the general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, can also make some simple deduction or replace, all should be considered as belonging to protection scope of the present invention.