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CN102909612A - Method for grinding self-centering drill bit - Google Patents

Method for grinding self-centering drill bit Download PDF

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Publication number
CN102909612A
CN102909612A CN2011102161786A CN201110216178A CN102909612A CN 102909612 A CN102909612 A CN 102909612A CN 2011102161786 A CN2011102161786 A CN 2011102161786A CN 201110216178 A CN201110216178 A CN 201110216178A CN 102909612 A CN102909612 A CN 102909612A
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CN
China
Prior art keywords
reconditioning
point
drill bit
knife
self
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Application number
CN2011102161786A
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Chinese (zh)
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CN102909612B (en
Inventor
赵良飞
温海源
范立杰
董博
贾乐坤
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Rizhao Weipai Automobile Co ltd
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Great Wall Motor Co Ltd
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Publication of CN102909612A publication Critical patent/CN102909612A/en
Application granted granted Critical
Publication of CN102909612B publication Critical patent/CN102909612B/en
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  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Abstract

The invention belongs to the technical field of grinding for cutting edges of drill bits, and particularly relates to a method for grinding a self-centering drill bit. The self-centering drill bit is ground by a grinding wheel after being fixed. The method particularly includes steps of adjusting angles among various ground surfaces of the self-centering drill bit and the grinding wheel with a sharp corner; and sequentially grinding a first rear knife face of a knife point, a first rear knife face of a drill point, a second rear knife face of the knife point and a second rear knife face of the drill point of the self-centering drill bit. The method has the advantages that the drill bit is ground by existing common grinding equipment, the practicality is high, and the usage cost is lowered.

Description

The method of reconditioning self-centering drill bit
Technical field
The invention belongs to the technical field of the cutting edge of drill bit being carried out sharpening, relate in particular to a kind of method of reconditioning self-centering drill bit.
Background technology
Drill bit comes minute can be divided into two kinds of straight trough and helicla flutes by grooved, comes minute can be divided into right-handed screw angle and backpitch angle by the helical angle direction, and helical angle can vary according to actual needs.Come carbide alloy minute is arranged, high-speed steel, weld the PCD drill bit in addition from the cutter material.Handle of a knife has two kinds of staight shank and taper shanks.Present drill bit major part all is the straight shank carbide drill head, because present handle of a knife all is hydraulic pressure, the heat in addition solid fixed form of side that rises.Only have special plane seldom using taper-shank drill.Also abandon the in the past traditional idea of drill head apical angle 118 degree according to the drift angle of drill bit, difference can have more angle of drill bit to exist to begin to have more drill head apical angle to have 130 degree, 135 degree, 140 degree, 150 to spend as requested.Form by apex point has common apex point and the said self-centering apex point of this programme, also has a kind of special thin-walled apex point.Mostly adopt common apex point and self-centering apex point in the present high-speed cutting epoch, common apex point uses the most extensive.Because the self-centering drill bit reconditioning is difficult in maintenance, also very difficult even numerically control grinder is programmed sometimes, can not be unified as the batch production of cutter producer.So common apex point is widely used, but in order to locate accurately rapidly the raising productive temp, still a lot of companies realize quick and precisely locating with this self-centering drill bit and realize that high number cuts.
Be showing improvement or progress day by day along with manufacturing, more and more higher to precision and the working (machining) efficiency requirement of workpiece.The self-centering apex point replaces common apex point just gradually.Thereby realization high-speed cutting fast location is enhanced productivity, but this type of reconditioning maintenance is very difficult.Because this type of drill bit apex point is made of two parts, the one, the apex point of locating fast, the 2nd, the point of a knife of high-speed cutting.Utilize conventional equipment when reconditioning, because common polishing device is only to finish common rectilinear motion, can not realize that point of a knife is interfered during the reconditioning apex point as the numerically control grinder poor function of mending of programming away, apex point is interfered during the reconditioning point of a knife.Namely use high accuracy five travelling wheelhead roll grinders to require high especially to programming personnel's technical ability.Reconditioning and recycling to cutter bring great inconvenience.Cause the cost of charp tool high, because of can't self-healing after the tool wear, need appoint other unit or return factory and carry out reconditioning, expense be generally new cutter 30% or more.Need the reconditioning expense of payment great number, cause enterprise's cost of charp tool high; Simultaneously long because of the cutter grinding cycle, need the volume of the circular flow of increase cutter just can not affect normal use, cause the occupation of capital to enterprise, bring economically loss to enterprise.
Summary of the invention
Be to solve the deficiencies in the prior art, the invention provides a kind of method of reconditioning self-centering drill bit, it has realized grinding to drill bit by existing common polishing device, and practicality is high, has reduced use cost.
For achieving the above object, the method of reconditioning self-centering drill bit of the present invention, after pilot bit is fixing, adopting, bowl type or the dish (emery) wheel of point carry out reconditioning to pilot bit, the method is carried out grinding to point of a knife major first flank, apex point major first flank, point of a knife the second rear knife face, the apex point second rear knife face of pilot bit in turn by each reconditioning face of adjustment pilot bit and the angle between the angular emery wheel of tool.
As the restriction to aforesaid way, described emery wheel is bowl abrasive wheel or dish (emery) wheel.
Specifically, the method for reconditioning self-centering drill bit of the present invention comprises the steps:
Step 1, fixing of self-centering drill bit on the cutter clamping axle, makes the center line of pilot bit parallel with the axis of cutter clamping axle the pilot bit clamping;
Step 2, the emery wheel angle is adjusted in the reconditioning of point of a knife major first flank, and emery wheel is upwarped, and the relative point of a knife major first flank of emery wheel forms the first relief angle of 7 ~ 10 degree; Feeding reconditioning pilot bit, by emery wheel with the major first flank reconditioning of pilot bit to the point of a knife place, one of them point of a knife major first flank reconditioning is put in place; Behind self-centering drill bit Rotate 180 degree, to another point of a knife major first flank reconditioning position;
Step 3, the cutter clamping axle is adjusted in the reconditioning of apex point major first flank, makes to have half angle of apex point between itself and the emery wheel wedge angle place end face, by emery wheel point of a knife major first flank place is arrived in the reconditioning of apex point major first flank, one of them major first flank reconditioning puts in place to apex point; Behind self-centering drill bit Rotate 180 degree, another major first flank reconditioning puts in place to apex point;
Step 4, point of a knife the second rear knife face reconditioning is based on step 3, with lifting 10 ~ 15 degree on the cutter clamping axle, take land as benchmark, grind length by control point of a knife the second rear knife face, by emery wheel with the second rear knife face reconditioning to the point of a knife place, one of them point of a knife second rear knife face reconditioning is put in place; Behind self-centering drill bit Rotate 180 degree, another point of a knife second rear knife face reconditioning is put in place;
Step 5, apex point the second rear knife face reconditioning, adjust the cutter clamping axle, make and have half angle of apex point between itself and the emery wheel wedge angle place end face, by controlling amount of grinding to form apex point major first flank width, use emery wheel that point of a knife the second rear knife face place is arrived in apex point the second rear knife face reconditioning, one of them second rear knife face reconditioning puts in place to apex point; Behind self-centering drill bit Rotate 180 degree, another second rear knife face reconditioning puts in place to apex point.
Further, step 6 is opened chisel edge, and grinding width by emery wheel is the horizontal tough of 0.2mm-0.3mm.
As the restriction to aforesaid way, after above steps puts in place to knife face reconditioning after each of self-centering drill bit, all process an equal amount of grinding.
As the further restriction to aforesaid way, above-mentioned amount of grinding is 0.2mm.
As the improvement to aforesaid way, above-mentioned self-centering drill bit is fixed on the cutter clamping axle by the spring chuck.
As the restriction to aforesaid way, before step 1, comprise the inspection step of beating, self-centering drill bit is clipped when being installed on the cutter clamping axle with the spring clip cover, the axis jerk value of the relative cutter clamping axle of cutter is checked.
As the further restriction to aforesaid way, described cutter jerk value is 0.02mm.
Adopt technique scheme, utilize the characteristics of bowl abrasive wheel or dish (emery) wheel wedge angle, carrying out branch by each the rear knife face with self-centering drill bit grinds in turn, realized preferably grinding effect, the prosthetic appliance that has solved self-centering drill bit drops into, can again utilize after making the self-centering drill bit reconditioning, require lower to equipment and personnel.
Description of drawings
Below in conjunction with the drawings and the specific embodiments the present invention is done further to describe in detail:
Fig. 1 is the overall structure schematic diagram of the self-centering drill bit that the present invention relates to;
Fig. 2 is the right view of Fig. 1.
Among the figure:
1, apex point; 11, apex point major first flank; 12, apex point the second rear knife face; 2, point of a knife; 21, point of a knife major first flank; 22, point of a knife the second rear knife face.
The specific embodiment
The below is described in detail as follows method of the present invention take existing typical carbide straight trough self-centering drill bit as example:
By as can be known shown in Figure 1, the cutting tip of this self-centering drill bit mainly is comprised of apex point 1 and point of a knife 2 two parts, and as seen from Figure 2, this self-centering drill bit has the combining structure of apex point 1 and point of a knife 2.Wherein, apex point 1 apex point major first flank 11 and apex point the second rear knife face 12, point of a knife 2 point of a knife major first flanks 21 and point of a knife the second rear knife face.
When above-mentioned self-centering drill bit is repaired, the general thought of its reparation is that drill bit is decomposed, by each reconditioning face of adjustment pilot bit and the angle between the angular emery wheel of tool, in turn point of a knife major first flank 21, apex point major first flank 11, point of a knife the second rear knife face 22, the apex point second rear knife face 12 of pilot bit are carried out grinding.Emery wheel adopts bowl abrasive wheel (11V9) or dish (emery) wheel (12V9).
Its concrete method of grinding comprises the steps:
Step 1, be installed on the equipment with cutter clamping axle after pilot bit clipped with spring housing, adopt beating of magnetic power meter or centimeter check drill bit installation, specifically magnetic stand is adsorbed on the height that detects two points of a knife on the equipment, gauge outfit is contacted point of a knife write down the dial gauge reading, then cutter Rotate 180 degree is measured the height of another point of a knife, illustrate that too greatly then cutter clamping has problem to need to adjust if differ, guarantee beating at 0.02mm of cutter, so that the dead in line of the center line of pilot bit and cutter clamping axle;
Step 2,21 reconditionings of point of a knife major first flank are adjusted to level with the clamping axle that cutter is housed, and are vertical with center line of bit with the drill bit main cutting edge of guaranteeing reconditioning, and at this moment, emery wheel is parallel with cutter.Adjust the emery wheel angle, make grinding wheel spindle upwards lift 7 ~ 10 degree, make the relative point of a knife major first flank of emery wheel form the first relief angle of 7 ~ 10 degree, will use the grinding wheel diameter maximum here, to guarantee the quality of reconditioning apex point as far as possible.By the hand feed pilot bit, make the point of a knife major first flank 21 of pilot bit contact the beginning reconditioning with emery wheel, the each amount of feeding of pilot bit is that 0.01mm is advisable, by emery wheel with point of a knife major first flank 21 reconditionings of pilot bit to the point of a knife place, one of them point of a knife major first flank reconditioning is put in place, and then the amount of grinding about feeding reconditioning 0.2mm, reconditioning this position under the postscript that puts in place; Behind self-centering drill bit Rotate 180 degree, after another point of a knife major first flank 21 reconditionings were put in place, same amount of grinding about feeding reconditioning 0.2mm was with good with the wearing part reconditioning;
Step 3,11 reconditionings of apex point major first flank, take apex point angle partly as 120 degree as example, adjust the cutter clamping axle, make the monolateral formation 60 degree angles of the nose part of cutter clamping axle and emery wheel, stop the emery wheel feeding when by emery wheel the apex point major first flank being repaired a die point of a knife major first flank place, then the reconditioning another side repeatedly grinds the relief cutter and marches forward about 0.2mm; Behind self-centering drill bit Rotate 180 degree, after another major first flank reconditioning of apex point, allow cutter march forward about 0.2mm, to realize the slitless connection of apex point major first flank 11 and point of a knife major first flank 21;
Step 4, point of a knife the second rear knife face 22 reconditionings, this step medium plain emery wheel and equipment state and step 2 are basic identical, just based on step 3, will lift 10 ~ 15 degree, gradually feeding reconditioning on the cutter clamping axle.Method and reconditioning point of a knife major first flank are basic identical, just to control reconditioning quality, width with the control major first flank, the width of general major first flank is about 0.3 ~ 0.5mm, owing to be difficult for dismantling measurement, so this width can be take the land of cutter as benchmark, width is the same with margin width just can to make the length of the second rear knife face and major first flank length consistent, grind length by control point of a knife the second rear knife face, by emery wheel with the second rear knife face reconditioning to the point of a knife place, one of them point of a knife second rear knife face reconditioning is put in place, then the amount of grinding about feeding reconditioning 0.2mm; Behind self-centering drill bit Rotate 180 degree, another point of a knife second rear knife face reconditioning is put in place, again the amount of grinding about feeding reconditioning 0.2mm;
Step 5, apex point the second rear knife face 12 reconditionings, this step and step 3 are basic identical, difference is based on step 4, adjusts the cutter clamping axle, make its with emery wheel wedge angle place end face between form 60 and spend angles.
Step 6 is opened chisel edge, and grinding width by emery wheel is the horizontal tough of 0.2mm-0.3mm.

Claims (9)

1. the method for a reconditioning self-centering drill bit, after pilot bit is fixing, adopt emery wheel that pilot bit is carried out reconditioning, it is characterized in that: the method is carried out grinding to point of a knife major first flank, apex point major first flank, point of a knife the second rear knife face, the apex point second rear knife face of pilot bit in turn by each reconditioning face of adjustment pilot bit and the angle between the angular emery wheel of tool.
2. the method for reconditioning self-centering drill bit according to claim 1 is characterized in that: described emery wheel is bowl abrasive wheel or dish (emery) wheel.
3. the method for reconditioning self-centering drill bit according to claim 1 and 2 is characterized in that the method comprises the steps:
Step 1, fixing of self-centering drill bit on the cutter clamping axle, makes the center line of pilot bit parallel with the axis of cutter clamping axle the pilot bit clamping;
Step 2, the reconditioning of point of a knife major first flank; Adjust the emery wheel angle, emery wheel is upwarped, and the relative point of a knife major first flank of emery wheel forms the first relief angle of 7 ~ 10 degree, feeding reconditioning pilot bit, by emery wheel with the major first flank reconditioning of pilot bit point of a knife to the point of a knife place, one of them point of a knife major first flank reconditioning is put in place; Behind self-centering drill bit Rotate 180 degree, another point of a knife major first flank reconditioning is put in place;
Step 3, the cutter clamping axle is adjusted in the reconditioning of apex point major first flank, makes to have half angle of apex point between itself and the emery wheel wedge angle place end face, by emery wheel point of a knife major first flank place is arrived in the reconditioning of apex point major first flank, one of them major first flank reconditioning puts in place to apex point; Behind self-centering drill bit Rotate 180 degree, another major first flank reconditioning puts in place to apex point;
Step 4, point of a knife the second rear knife face reconditioning is based on step 3, with lifting 10 ~ 15 degree on the cutter clamping axle, take land as benchmark, grind length by control point of a knife the second rear knife face, by emery wheel with the second rear knife face reconditioning to the point of a knife place, one of them point of a knife second rear knife face reconditioning is put in place; Behind self-centering drill bit Rotate 180 degree, another point of a knife second rear knife face reconditioning is put in place;
Step 5, apex point the second rear knife face reconditioning, adjust the cutter clamping axle, make and have half angle of apex point between itself and the emery wheel wedge angle place end face, by controlling amount of grinding to form apex point major first flank width, use emery wheel that point of a knife the second rear knife face place is arrived in apex point the second rear knife face reconditioning, one of them second rear knife face reconditioning puts in place to apex point; Behind self-centering drill bit Rotate 180 degree, another second rear knife face reconditioning puts in place to apex point.
4. the method for reconditioning self-centering drill bit according to claim 3 is characterized in that:
Step 6 is opened chisel edge, and grinding width by emery wheel is the horizontal tough of 0.2mm-0.3mm.
5. the method for reconditioning self-centering drill bit according to claim 3 is characterized in that: after knife face reconditioning after each of self-centering drill bit is put in place, all process an equal amount of grinding.
6. the method for reconditioning self-centering drill bit according to claim 5, it is characterized in that: described amount of grinding is 0.2mm.
7. the method for reconditioning self-centering drill bit according to claim 3, it is characterized in that: described self-centering drill bit is fixed on the cutter clamping axle by the spring chuck.
8. the method for reconditioning self-centering drill bit according to claim 7, it is characterized in that: before step 1, comprise the inspection step of beating, self-centering drill bit is clipped when being installed on the cutter clamping axle with the spring clip cover, the axis jerk value of the relative cutter clamping axle of cutter is checked.
9. the method for reconditioning self-centering drill bit according to claim 8, it is characterized in that: described cutter jerk value is 0.02mm.
CN201110216178.6A 2011-07-31 2011-07-31 Method for grinding self-centering drill bit Expired - Fee Related CN102909612B (en)

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CN102909612B CN102909612B (en) 2014-12-03

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104227093A (en) * 2014-09-12 2014-12-24 广西玉林达业机械配件有限公司 Drill point centering countersinking cutter
JP2019166591A (en) * 2018-03-22 2019-10-03 株式会社不二越 Drill
CN112643414A (en) * 2020-12-09 2021-04-13 航天科工哈尔滨风华有限公司 Method for processing and manufacturing hard alloy drill bit

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CN101053940A (en) * 2007-04-17 2007-10-17 湖南大学 Sharpening method for drill tip back knife face of fully screw face drill
CN101081483A (en) * 2007-04-17 2007-12-05 湖南大学 Full helicoidal surface Micro-drill web thinning method

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB932422A (en) * 1958-12-11 1963-07-24 Birmingham Small Arms Co Ltd Improvements in or relating to the pointing of drills
JPS5577453A (en) * 1978-11-29 1980-06-11 Seiichi Tsunoda Drill grinding machine
CN2158766Y (en) * 1992-10-31 1994-03-16 西南石油学院 Hand-driven cutter grinding device for group drills
CN1295903A (en) * 2000-12-08 2001-05-23 王存厚 Other axle helicoidal surface grinding method and edge-grinding machine for cutting edge of twist drill
CN101053940A (en) * 2007-04-17 2007-10-17 湖南大学 Sharpening method for drill tip back knife face of fully screw face drill
CN101081483A (en) * 2007-04-17 2007-12-05 湖南大学 Full helicoidal surface Micro-drill web thinning method

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吕彦明等: "复杂螺旋面钻尖刃磨原理及实现", 《中国机械工程》, vol. 11, no. 3, 30 March 2000 (2000-03-30) *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104227093A (en) * 2014-09-12 2014-12-24 广西玉林达业机械配件有限公司 Drill point centering countersinking cutter
JP2019166591A (en) * 2018-03-22 2019-10-03 株式会社不二越 Drill
JP7082750B2 (en) 2018-03-22 2022-06-09 株式会社不二越 Drill
CN112643414A (en) * 2020-12-09 2021-04-13 航天科工哈尔滨风华有限公司 Method for processing and manufacturing hard alloy drill bit

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