JP5256240B2 - Workpiece machining method using reamer - Google Patents

Description

  The present invention relates to a reamer and a method for machining a workpiece using the reamer, and more particularly to a reamer for machining a through hole.

  Conventionally, cutting tools are disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-170810 (Patent Document 1), Japanese Patent Application Laid-Open No. 11-309616 (Patent Document 2), Japanese Patent Application Laid-Open No. 2003-117768 (Patent Document 3), and Japanese Patent Application Laid-Open No. 2003-2003. No. 1511 (Patent Document 4), JP-A 2003-1522 (Patent Document 5), JP-A 2000-263328 (Patent Document 6) and JP-A 6-320323 (Patent Document 7). ing.

JP 2001-170810 A JP-A-11-309616 JP 2003-117768 A JP 2003-1511 A JP 2003-1522 A JP 2000-263328 A JP-A-6-320323

  In Patent Document 1, in a twist drill in which a heat-resistant film is coated and the base material is made of high speed steel, cemented carbide or TiCN cermet, the coolant hole is cut at least on the third surface when viewed from the shaft end of the twist drill. A twist drill with a coolant hole, which is characterized by being opened to the waste discharge groove side, is disclosed.

  In Patent Document 2, an oil mist introduction hole penetrating from the root portion toward the tip portion is provided, and the sum of the cross-sectional areas of the two injection ports is larger than the cross-sectional area of the upstream portion of the oil mist introduction hole. A configuration is disclosed in which the speed of the oil mist injected from the injection port is increased by reducing the size.

  In Patent Document 3, compressed air supply means for supplying compressed air, compressed air supplied by the compressed air supply means, oil mist forming means for generating oil in a mist form, and oil mist forming means are used. Piping means for guiding compressed air containing generated oil mist to a predetermined injection site and nozzle means provided at the tip of the piping means are disclosed.

  In patent document 4, it is a semi-dry processing tool provided with the cutting edge, the front-end | tip part which has the twisted blade groove | channel for discharging | emitting a chip | tip, and the shank part which continues to a front-end | tip part, Comprising: There is disclosed a semi-dry processing tool provided with a mist passage for communicating and discharging mist to a twisted blade groove.

  In Patent Document 5, a rough edge for rough machining, a tip portion having a finishing blade having a larger processing radius than the rough blade, and a shank portion continuous to the tip portion are provided, and the tip of the finishing blade is the tip of the cutting blade. A semi-dry working tool is disclosed in which the distance from the axial center of the tip portion of the portion provided with at least the flute on the shank portion side of the finishing blade is smaller than the processing radius.

  In Patent Document 6, a cutting blade body made of a high-hardness sintered body having the same outer diameter as the blade diameter portion is joined to the tip of the blade diameter portion extending from a cemented carbide or steel shank. A plurality of continuous blade grooves are formed on the outer periphery of the part, the oil hole is formed in the center of the shank, from the rear end of the shank to just before the joint, and the injection hole is joined radially from the oil hole to the shank tip The structure which is formed so that it may reach in the blade groove near a part and forms a blade groove in a left-handed twist is disclosed.

  In Patent Document 7, the cutting tool is composed of a tool body and a shank, and a supply hole is provided through the central portion of the shaft. The tool body is twisted so as to be involved in cutting. A chip discharge groove, a tip cutting edge ridge, an outer peripheral cutting edge ridge, and the like are formed, and at least one of the chip discharge grooves is formed deep toward the center of the axis, and accordingly, a discharge hole between the supply hole and the supply hole. The structure which opens is disclosed.

  According to the so-called mist refueling method in which oil mist is supplied to a cutting site using a conventional cutting tool and mist supply device, the air force is weaker than that in the case of supplying cutting oil directly to the cutting site. The ability to remove is poor. For this reason, there has been a problem that the chips are caught in the gap between the reamer and the workpiece, causing deterioration of finishing accuracy and generation of scratches on the finished surface.

  Accordingly, the present invention has been made to solve the above-described problems, and an object thereof is to provide a reamer capable of improving the accuracy of a finished surface and a method of machining a workpiece using the reamer. And

A method of machining a workpiece using a reamer according to the present invention is a machining method of a workpiece using a reamer that rotates around a rotation axis, which is compatible with a mist refueling method, in which an ultra-hard chip is fixed to a base metal. The reamer is provided with an oblique groove on the outer peripheral surface so as to extend inclined with respect to the rotation axis, the oblique groove accommodates the super-hard chip, and the inclination formed by the oblique groove with respect to the rotation axis. In order to supply mist to the rake face side and the flank face side, the angle is -3 ° to -15 °, the guide pad is not provided, and the refracting face and the rake face are provided on the super hard chip. A hole opened in the surface of the reamer is provided, and mist is supplied from the hole on the rake face side to the surface of the workpiece just before being processed with the super hard tip.

In the reamer configured as described above, the inclination angle formed by the oblique groove with respect to the rotation axis is from -3 ° to -15 °. Therefore, it is possible to discharge chips efficiently and improve the accuracy of the finished surface. It becomes possible.

  Further, by not providing the guide pad, chips are not caught between the guide pad and the workpiece, and the accuracy of the finished surface can be improved.

  More preferably, an angle formed between a line connecting the opening of the rake face side hole and the rotation axis when viewed from the reamer tip side and a line connecting the opening of the hole on the flank face side and the rotation axis is 45 ° or less. .

More preferably, both the rake face side hole and the flank face side hole extend linearly in the vicinity of the reamer surface, and the direction in which the rake face side hole extends is 15 ° or more and 45 ° with respect to the rotation axis. The angle is 20 ° or more and 30 ° or less when viewed from the front end side with respect to the front cutting edge of the rake face, and the extending direction of the hole on the flank face is 15 with respect to the rotation axis. An angle of not less than 45 ° and not more than 45 ° is formed, and an angle of not less than 45 ° and not more than 60 ° when viewed from the front end side with respect to the front cutting edge of the rake face.

Preferably, the material of the workpiece to be processed with the reamer is a non-ferrous metal material.
The method according to the present invention is a processing method of a workpiece using the above-described reamer, and mist is supplied from a hole on the rake face side to the surface of the workpiece just before being processed with an ultra-hard chip.

  According to the present invention, it is possible to provide a reamer for processing through holes that can improve the accuracy of the finished surface.

It is a perspective view of the reamer for through-hole processing according to an embodiment. It is a perspective view which shows the super-hard chip | tip attached to the front-end | tip of the reamer according to embodiment. It is a reamer's perspective view which shows the mist channel | path in a reamer. It is a perspective view of the reamer seen from another direction. It is the perspective view of the reamer seen from another direction. It is a figure for demonstrating the angle of a flute. It is the front view of a reamer seen from the direction shown by arrow VII in FIG. It is a perspective view of the reamer seen from another direction. FIG. 2 is a rear view of the reamer viewed from a direction indicated by an arrow IX in FIG. 1. It is a figure which shows the front-end | tip part of a main channel | path. It is a figure which shows the direction where the rake face side hole extends seen from the front end side. It is a figure for demonstrating a guide pad. It is the front view seen from the direction shown by XIII in FIG. It is a figure of the reamer of the clockwise left twist blade for demonstrating a twist angle. It is a figure of the reamer of the clockwise right twist blade for demonstrating a twist angle. It is a figure which shows the locus | trajectory of the flow of the air inject | poured from the opening on condition of the rotation speed 6000min < ^-1 > and flow volume 86dm < ³ > / min with this invention product 1. FIG. It is a figure which shows the locus | trajectory of the flow of the air injected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 86dm < ³ > / min in the comparative example 1. FIG. It is a figure which shows the locus | trajectory of the flow of the air injected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 86dm < ³ > / min in the comparative example 2. FIG. It is a figure which shows the locus | trajectory of the flow of the air injected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 86dm < ³ > / min in the comparative example 3. FIG. It is a figure which shows the locus | trajectory of the flow of the air ejected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 86dm < ³ > / min in the comparative example 4. FIG. It is a figure which shows the locus | trajectory of the flow of the air injected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 86dm < ³ > / min in the comparative example 7. FIG. It is a figure which shows the locus | trajectory of the flow of the air ejected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 86dm < ³ > / min in the comparative example 8. FIG. It is a figure which shows the locus | trajectory of the flow of the air inject | poured from the opening on the conditions of rotation speed 12000min < ^-1 > and flow volume 86dm < ³ > / min with this invention product 1. FIG. It is a figure which shows the locus | trajectory of the flow of the air ejected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 186dm < ³ > / min in the comparative example 1. FIG. It is a figure which shows the locus | trajectory of the flow of the air injected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 186dm < ³ > / min in the comparative example 2. FIG. It is a figure which shows the locus | trajectory of the flow of the air ejected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 186dm < ³ > / min in the comparative example 3. FIG. It is a figure which shows the locus | trajectory of the flow of the air ejected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 186dm < ³ > / min in the comparative example 4. FIG. It is a figure which shows the locus | trajectory of the flow of the air ejected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 186dm < ³ > / min in the comparative example 7. FIG. It is a figure which shows the locus | trajectory of the flow of the air ejected from the opening in conditions of rotation speed 6000min < ^-1 > and flow volume 186dm < ³ > / min in the comparative example 8. FIG. It is a figure which shows the locus | trajectory of the flow of the air inject | poured from the opening on the conditions of rotational speed 12000min < ^-1 > and flow volume 186dm < ³ > / min with this invention product 1. FIG.

  Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

  FIG. 1 is a perspective view of a reamer for processing through holes according to an embodiment. Referring to FIG. 1, a reamer 100 is a cutting tool for machining a through hole, and has a reamer main body 10. The reamer body 10 as a base metal extends in the longitudinal direction. A flute 110 is provided on the outer peripheral surface 19 of the reamer main body 10 as a shank so as to extend inclined with respect to the longitudinal direction. The flute 110 has a linear shape. The reamer body 10 rotates in the direction indicated by the arrow R1.

  In the vicinity of the flute 110, a rake face side opening 11 and flank face side openings 111 and 112 are provided. The rake face side opening 11 and the flank face side openings 111 and 112 are holes for supplying oil mist, respectively.

  An ultrahard tip 2 is attached to the tip of the flute 110. In this example, two super-hard chips 2 are attached. In this example, the super-hard chip on the front side has a rake face 21, a front flank 212, and a side flank 211. The inner superhard chip 2 has a front flank 222.

  FIG. 2 is a perspective view showing a super hard tip attached to the tip of the reamer according to the embodiment. Referring to FIG. 2, superhard tip 2 is made of diamond, cubic boron nitride (CBN), cemented carbide or the like. The super hard chip 2 has a rake face 21, a front flank 212, and a side flank 211. A boundary region between the front flank 212 and the rake face 21 is a front cutting edge 213. A boundary part that separates the margin width from the side flank 211 and the rake face 21 is a side cutting edge 214. The ultra-hard chip on the back side in FIG. 1 adopts the same configuration as in FIG.

  On the rake face, portions other than the front cutting edge 213 and the side cutting edge 214 are curved. The super-hard chip 2 has a thin plate shape and is fixed to the reamer body 10 by brazing.

  FIG. 3 is a perspective view of the reamer showing the mist passage in the reamer. Referring to FIG. 3, a main passage 150 is provided in the center of the reamer body 10. The flank side holes 151 and 153 and the rake side hole 155 extend so as to branch from the central main passage 150. The tip portions of the flank face holes 151 and 153 are flank face side openings 112 and 111, and the tip portion of the rake face side hole 155 is a rake face side opening 11. The rake face side opening 11 and the flank face openings 111 and 112 are each configured in an elliptical shape.

  In this example, six holes are branched from the main passage 150, but the present invention is not limited to this, and more or fewer holes may be branched from the main passage 150.

  In this example, the main passage 150 is on the rotation axis. However, the present invention is not limited to this, and a plurality of main passages are provided at positions different from the rotation shaft and branch off from these main passages. As such, a hole may be provided.

  FIG. 4 is a perspective view of the reamer viewed from another direction. FIG. 5 is a perspective view of the reamer viewed from another direction. Referring to FIG. 4, the flute 110 extends linearly from the base side to the tip side of the reamer body 10. The super hard tip 2 in the flute 110 is lubricated by oil mist. The flank holes 151 and 153 branched from the main passage 150 supply oil mist to the flank face. On the other hand, the rake face side hole 155 supplies oil mist to the rake face side of the super hard chip 2. By this oil mist, friction between the workpiece and the super hard tip 2 can be reduced, and heat generated between the workpiece and the super hard tip 2 can be diffused.

  This reamer employs a mist lubrication method in which a small amount of cutting fluid is mixed (mixed) with high-pressure air and supplied to the cutting point. By adopting MQL (Minimal Quantity Lubricants) processing that optimizes the supply of cutting fluid as low as possible, environmental measures can be taken.

  Referring to FIG. 5, exposed flank openings 111 and 112 supply mist to the side flank 221 side. In this example, mist is supplied from the two flank face openings 111 and 112 to the flank face, but mist may be supplied to the flank face from a larger or smaller number of openings.

  FIG. 6 is a diagram for explaining the flute angle. Referring to FIG. 6, a reamer 100 shown in the embodiment has a clockwise left twist blade. Note that the reamer 100 may be a left-handed right-hand twist blade. The sign of the angle θ formed by the flute 110 and the rotary shaft 1 as the central axis in the right-handed left-handed blade reamer and the right-handed right-handed blade reamer is negative. In the present invention, the angle is −3 °. To -15 °. In order to have such a negative twist angle, in the reamer 100, the rake face 21 is disposed so as to be bent forward in the cutting direction.

  FIG. 7 is a front view of the reamer viewed from the direction indicated by the arrow VII in FIG. Referring to FIG. 7, the tip of the reamer body 10 has a rotationally symmetric (point symmetric) shape. Super hard chips 2 are attached to each of the left and right sides. The front flank surfaces 212 and 222 of the super-hard chip 2 are arranged at a distance from each other. The front flank surfaces 212 and 222 are arranged so as to extend in the radial direction. The rake surfaces 21 and 22 are provided so as to continue to the front flank surfaces 212 and 222. Since the flutes 110 and 210 are inclined with respect to the rotation axis 1, the rake surfaces 21 and 22 can be seen from the front. A boundary between the rake face 21 and the front flank 212 is a front cutting edge 213. The front cutting edge 213 is further connected to the side cutting edge 214.

  A boundary between the rake face 21 and the front flank 212 is a front cutting edge 213. The boundary between the rake face 22 and the front flank 222 is the front cutting edge 223.

  The front cutting edges 213 and 223 are used when the reamer 100 is used in an application similar to a drill. Specifically, when finishing a hole having a radius sufficiently smaller than the rotation radius of the super hard tip 2 by the reamer 100, the front cutting edges 213 and 223 act to process the hole. On the other hand, when machining a hole having a rotation radius substantially equal to the rotation radius of the super-hard chip 2, the front cutting edges 213 and 223 hardly function.

  FIG. 8 is a perspective view of the reamer viewed from another direction. Referring to FIG. 8, a main passage 150 is opened on the back side of the reamer 100. The mist sent from the main passage 150 exhibits a lubricating action by being ejected from the rake face side opening 11 and the flank face side opening 111 existing on the tip side.

  FIG. 9 is a rear view of the reamer viewed from the direction indicated by the arrow IX in FIG. Referring to FIG. 9, in the rear view, a hollow main passage 150 is located at the center of the cylindrical reamer 100. A rake face side hole 155 is located at the end of the main passage 150.

  Further, rake face side openings 11 and flank face side openings 111 are provided on both sides of the front cutting edge 213. The angle A formed by the straight line connecting the rotation axis and the rake face side opening 11 and the straight line connecting the rotation axis and the flank face opening 111 is preferably 45 ° or less, and the rake face is close to the super hard chip. The rake face side opening 11 and the flank face side opening 111 are preferably arranged.

  FIG. 10 is a diagram showing a tip portion of the main passage. Referring to FIG. 10, main passage 150 is a blind hole, and rake face side hole 155 is separated at the tip portion. The rake face side hole 155 extends linearly, and the angle formed with the rotary shaft 1 is α. α is preferably 15 ° or more and 45 ° or less.

  FIG. 11 is a diagram illustrating a direction in which the rake face side hole extends as viewed from the distal end side. Referring to FIG. 11, in the front view, the angle between the front cutting edge 213 that is the end of the rake face 21 and the direction in which the rake face side hole 155 extends is β. This angle is preferably 20 ° or more and 30 ° or less.

  The flank holes 151 and 153 have an angle α of 15 ° or more and 45 ° or less with respect to the rotary shaft 1 and an angle β of 45 ° or more and 60 ° or less with respect to the front cutting edge 213 of the rake face. Is preferred. It has a PCD margin width of width L.

  FIG. 12 is a diagram for explaining the guide pad. As shown in FIG. 12, the reamer body 10 may be provided with a guide pad 18 made of, for example, carbide. FIG. 13 is a front view seen from the direction indicated by XIII in FIG. As shown in FIGS. 12 and 13, when the guide pad 18 is provided, the diameter of the guide pad 18 is increased. While machining the workpiece with the super-hard chip 2, the processing blade is finished in the guide pad 18. The guide pad 18 is not provided in the reamer according to this embodiment. As a result, it is possible to prevent chips from entering between the guide pad 18 and the workpiece and reducing the accuracy of the finished surface of the workpiece.

  In reamer 100 according to the embodiment, a guide pad is not provided. Therefore, the outer peripheral surface of the super hard chip 2 forms the outermost periphery of the reamer 100.

  FIG. 14 is a view of a reamer of a clockwise left twist blade for explaining a twist angle. FIG. 15 is a diagram of a reamer of a clockwise clockwise twist blade for explaining a twist angle. Referring to FIG. 14, in the clockwise left helix blade reamer, the rake face is provided so as to be bent forward in the cutting direction. At this time, in the left helix blade, the angle a, which is the working angle of the ridge line of the outer peripheral cutting edge, is a negative angle, and thus a force that hinders the reamer propulsion is generated. This force acts to push the reamer into the machine mounting shaft during machining.

  On the other hand, the force in the reverse direction is applied to the reamer having the right twist blade shown in FIG. The sign of angle a in FIG. 14 is minus, and the sign of angle b in FIG. 15 is plus.

  In the present invention, the sign of the working angle is minus, that is, a reamer having a right-handed left-handed blade or a right-handed right-handed blade is employed.

  The reamer 100 is a reamer 100 in which an ultra-hard chip 2 is fixed to the reamer main body 10 and is compatible with the mist refueling method. The reamer 100 has an outer peripheral surface 19 extending so as to be inclined with respect to the longitudinal direction. Is provided with a flute 110 as an oblique groove, an angle θ formed by the flute 110 with respect to the longitudinal direction is −3 ° to −15 °, and no guide pad is provided. Reamer for drilling. The angle that is bent forward with respect to the rotation direction is the negative angle θ.

  The super-hard chip 2 is provided with a front flank 212, a side flank 211, and a rake face 21, and a rake face side on the surface of the reamer 100 for supplying mist to the rake face side and the flank face side. An opening 11 and flank side openings 111 and 112 may be provided.

  An angle A formed by a line connecting the opening of the rake face side hole and the rotation axis when viewed from the reamer tip side and a line connecting the opening of the hole on the flank face side and the rotation axis is preferably 45 ° or less. . Both the rake face side hole 155 and the flank face side holes 151 and 153 extend linearly in the vicinity of the reamer surface, and the extending direction of the rake face side hole 155 is 15 ° or more and 45 ° or less with respect to the rotary shaft 1. And an angle β of 20 ° or more and 30 ° or less when viewed from the tip side with respect to the front cutting edge 213 at the tip of the rake face 21, and the direction in which the flank holes 151, 153 extend is It is preferable to make an angle of 15 ° to 45 ° with respect to the rotating shaft 1 and an angle β of 45 ° to 60 ° with respect to the front cutting edge 213 when viewed from the front end side. The material of the workpiece to be processed with the reamer is preferably a non-ferrous metal material. And in the processing method of the workpiece using the reamer 100, mist is supplied from the rake face side opening 11 to the surface of the workpiece just before being processed by the super hard tip 2.

Examples of the present invention will be described below.
In a mist environment, a tool verification comparison test was conducted to determine whether the required quality of the surface roughness (chip removal) was satisfied in the reamer hole finishing. The performance difference was compared by (1) surface roughness of the workpiece, (2) dimensional accuracy, (3) load current, and (4) state observation of the cutting edge (tool).

  A reamer was used under the machining conditions used in the automatic transmission (AT) transmission case line, and tool shapes suitable for mist environments were compared. For each sample, 50 holes were processed and evaluated. The pitch of adjacent holes was 16 mm in both the vertical and horizontal directions.

(1) Surface roughness (required accuracy 3.2 μm Rz)
The machined holes were cut vertically and the roughness was measured with a surface roughness meter (Accratach Surfcom '94JIS).

(2) Inner diameter (φ8 ^{+ 0.036 / 0} )
The plug gauge was used to measure whether or not the inner diameter was within the above dimensions, and the inside of the above inner diameter was OK, and the outside of the dimensions was NG. The numerical value of the inner diameter was measured with a three-point inner diameter micrometer at any one of 50 holes.

(3) Main shaft power (load current)
The spindle load voltage was output and the maximum value was read.

(4) Cutting edge observation The tool cutting edge before and after use was observed with a digital microscope (50 times magnification).

  Common processing conditions are shown in Table 1 below. Table 1 shows the specifications for specification selection evaluation. The on-machine runout of the tool was set to 5 μm or less.

  Table 2 shows the mist supply conditions.

  Table 3 shows the physical characteristics of mist oil. Mist oil is a plant-derived synthetic ester oil.

  That is, a pilot hole was formed under the conditions shown in Table 1, and this pilot hole was finished with a reamer having a rotating diameter of an ultra-hard chip of 8 mm.

  Table 4 shows the structures of the products of the present invention and the reamers of Comparative Examples 1 to 8.

In Table 4, the shapes of the product 1 of the present invention and Comparative Examples 1 to 8 are shown.
In the product 1 of the present invention, four chips are provided in the reamer body. Two chips are provided on the tip side of the reamer, the rotation diameter of this chip is 7.35 mm, and the rotation diameter of the two ultra-hard chips provided on the root side is 8 mm. In the tip side ultra-hard chip, an opening (oil hole) was provided only on the flank side. On the other hand, in the ultra-hard tip on the root side, openings are provided on the rake face side and the flank face side.

The “center” in Table 4 is the diameter of the main passage provided in the center of the reamer body.
In addition, in the present invention product and all the comparative products, the rotation diameter of the ultrahard tip on the tip side is 7.35 mm, and the minimum rotation diameter of the ultrahard tip on the root side is 8 mm.

  The “opening position (rake face side)” indicates the position of the opening provided on the rake face side of the ultra-hard chip having a minimum rotation diameter of 8 mm.

  “Opening position (flank face side)” indicates the position of an opening provided on the flank face side of a super hard chip having a minimum rotation diameter of 8 mm.

  “Branch” indicates the diameter and number of oil passages branched from the main passage and extending parallel to the rotation axis.

  In the sample having no branch passage, the diameter of the branch passage is the diameter of the main passage (center).

  In Comparative Examples 1 to 8, the shape of the flute is different from that of the present invention. Specifically, in the product of the present invention, the flute has an inclination of −8 °, whereas in Comparative Examples 1 to 8, a so-called straight flute parallel to the rotation axis was used. In both the product of the present invention and the comparative example, an ultrahard chip made of PCD was attached so that the direction in which the flute extends was parallel to the rake face.

  Further, in Comparative Example 1, the effect when the flank side was not lubricated and the effect when the carbide guide pad was provided were examined.

  In Comparative Example 2, the effect when the flank side was not lubricated and the effect when the carbide guide pad was provided were examined.

  In Comparative Example 3, the effect when the oil hole is not provided on the rake face side, the effect when the oil hole is provided at two locations at distances of 5, 13, and 5 mm from the shank tip on the flank side, and the effect due to the mist flow Examined.

In Comparative Example 4, the effect of providing two openings on the flank side was examined.
In Comparative Example 5, the effect of not providing an opening on the rake face side and the PCD (polycrystalline diamond) margin width effect were examined.

  In Comparative Example 6 and Comparative Example 7, the effect in the case where openings were provided at different positions in the axial direction on the flank side and no carbide guide pad was provided was examined.

In Comparative Example 8, the effect of processing a blind hole as a drill was examined.
Evaluation item 1
In the evaluation item 1, aiming at the improvement of the surface roughness due to the increase of the coolant and the prevention of vibration during processing, together with the product 1 of the present invention, Comparative Example 1 (Carbide Guide Pad) and Comparative Example 2 (Carbide Guide Pad are provided, Further, the effect was compared and verified under the processing conditions listed in Table 5 below.

  The carbide guide pad refers to a pad portion provided on a workpiece other than the PCD cutting blade that supports the tool on the workpiece along the rotating arc of the tool cutting blade.

As can be seen from Table 5, in Comparative Examples 1 and 2 provided with the guide pad, the surface roughness exceeded the specified value. Furthermore, the processing hole diameter also exceeded the standard value. In addition, “φ8 ^{+ 0.036 / 0} ” in the column of “Processing diameter” in Table 5 means that the upper limit of the allowable value of the processing hole dimension is 8 + 0.036 (mm) and the lower limit is 8 + 0 (mm). It shows that. In addition, (8.026) in this column indicates that the rotation diameter of the super hard chip was 8.026 mm.

  The results of evaluation item 1 are summarized as shown in Table 6.

Evaluation item 2
In evaluation item 2, as a measure for improving the surface roughness by avoiding aluminum welding of the carbide guide pad, Comparative Example 3 (discharging the mist from the flank shank of the PCD cutting blade and providing an oil groove in the carbide guide pad) ) And Comparative Example 4 (in addition to the shape of Comparative Example 3, oil holes were discharged from the rake face side), and the effects were compared and verified under the following conditions.

From Table 7, it was found that in Comparative Examples 3 and 4, the surface roughness of the inner surface was increased.
Table 8 summarizes the evaluation results for evaluation item 2.

Evaluation item 3
In evaluation item 3, as a measure for improving the surface roughness by reducing the burnishing effect of the cutting blade and avoiding aluminum welding of the carbide guide pad, Comparative Example 5 (the product of Comparative Example 3 was used and the PCD margin width was changed) and The products of Comparative Example 6 (in which the carbide guide pad was deleted using the product of Comparative Example 4) and Comparative Example 7 (in which the flow rate was increased) were prepared, and the effects were compared and verified under the processing conditions listed below. did.

From Table 9, it was found that in Comparative Examples 5 to 7, the surface roughness was increased.
Table 10 shows the result of evaluation item 3.

Evaluation item 4
In evaluation item 4, in order to confirm the influence on the hole shape to be processed, a comparative example 8 (drill) for blind holes was produced, and the effect was compared and verified under the following processing conditions.

  From Table 11, the discharge of chips was not suppressed in the blind hole, and the roughness on the tip side deteriorated. In the tool of Comparative Example 8, a hole that penetrated through the tool and opened at the tip of the tool was provided, and mist was ejected from this hole, but the lubrication effect by the mist was small.

  Based on Table 11, the results of Evaluation Item 4 are shown in Table 12.

Evaluation item 5
In Evaluation Item 5, the effect of the present invention was confirmed under the condition that the feed pitch was made fine by increasing the number of rotations of the spindle in order to improve the surface roughness without changing the required processing time range. . The results are shown in Table 13.

  From Table 13, it was found that when the rotational speed was increased, the surface roughness of the inner surface was better.

  The results for evaluation item 5 are shown in Table 14.

Evaluation item 6
In Evaluation Item 6, Comparative Examples 9 and 11 were prepared for the products 1 and 10 of the present invention. In Comparative Example 9, the flute twist angle was + 3 °, in the product 10 of the present invention, the flute twist angle was −3 °, and in Comparative Example 11, the flute twist angle was −20 °. And in order to confirm the influence which this difference in angle has on the surface roughness, each sample was evaluated. The results are shown in Table 15.

From Table 15, it was found that good surface characteristics can be obtained within the range of the present invention.
The results of evaluation item 6 are shown in Table 16.

Evaluation item 7
In the evaluation item 7, how the arrangement, size, and number of oil holes (openings) affect the mist distribution, and as a result, how the mist is distributed and flows was simulated. The mist flow rate was 86 dm ³ and 186 dm ³ . Then, it was examined how much mist is distributed at the tip of the reamer, the processed part, and the rest (dissipated part). The results are shown in Table 17.

FIG. 16 is a diagram showing a trajectory of the flow of air ejected from the opening in the product 1 of the present invention under the conditions of a rotational speed of 6000 min ⁻¹ and a flow rate of 86 dm ³ / min. FIG. 17 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 86 dm ³ / min in Comparative Example 1. FIG. 18 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 86 dm ³ / min in Comparative Example 2. FIG. 19 is a diagram showing a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 86 dm ³ / min in Comparative Example 3. FIG. 20 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 86 dm ³ / min in Comparative Example 4. FIG. 21 is a diagram showing a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 86 dm ³ / min in Comparative Example 7. FIG. 22 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 86 dm ³ / min in Comparative Example 8. FIG. 23 is a diagram showing a trajectory of the flow of air ejected from the opening in the product 1 of the present invention under the conditions of a rotational speed of 12000 min ⁻¹ and a flow rate of 86 dm ³ / min. FIG. 24 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 186 dm ³ / min in Comparative Example 1. FIG. 25 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 186 dm ³ / min in Comparative Example 2. FIG. 26 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 186 dm ³ / min in Comparative Example 3. FIG. 27 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 186 dm ³ / min in Comparative Example 4. FIG. 28 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 186 dm ³ / min in Comparative Example 7. FIG. 29 is a diagram illustrating a trajectory of the flow of air ejected from the opening under the conditions of the rotational speed of 6000 min ⁻¹ and the flow rate of 186 dm ³ / min in Comparative Example 8. FIG. 30 is a diagram showing a trajectory of the flow of air ejected from the opening in the product 1 of the present invention under the conditions of a rotational speed of 12000 min ⁻¹ and a flow rate of 186 dm ³ / min.

  16 to 30 show how mist is distributed in each sample. When the locus 900 in the figure is gathered at the tip portion and the processing portion, it can be seen that mist is supplied to the processing region, and preferable lubricating characteristics are obtained. On the other hand, in the example where mist is distributed in the dissipating part other than the tip part and the processed part (the reamer main body side where the cutting blade is not provided), the mist is not sufficiently supplied to the processed part, and a preferable result is obtained. I can't understand.

Evaluation item 8
In the evaluation item 8, it was examined how the twist angle, the presence / absence of the guide pad, and the presence / absence of the opening affect the hole accuracy of the workpiece after machining and the presence / absence of the scratch.

  In the product 101 of the present invention, the twist angle was set in increments of 2 ° from −3 ° to −15 °. In the products 102 and 103 of the present invention and the comparative example 101, the twist angle was set in increments of 2 ° as in the product 101 of the present invention. In Comparative Example 102, the twist angle was −2 °, and in Comparative Example 103, the twist angle was −16 °. Then, processing was performed under the same processing conditions as in Evaluation Item 1, and the hole accuracy and scratch state after processing were examined. The results are shown in Table 18.

  In Table 18, ◎ indicates particularly excellent, ○ indicates excellent, × indicates that there is a problem, and Δ indicates that there is a slight problem.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be used in the field of reamers.

  1 Rotating shaft, 2 Super hard tip, 10 Reamer body, 11 Rake face side opening, 18 Guide pad, 19 Outer peripheral face, 21, 22 Rake face, 100 Reamer, 110, 210 Flute, 111, 112 Relief face side opening, 150 Main passage, 151, 153 flank face side hole, 155 rake face side hole, 211 side flank face, 212 front flank face, 213 front cutting edge, 214 side cutting edge.

Claims (4)

A method of machining a workpiece using a reamer that rotates around a rotation axis, with an ultra-hard chip fixed to a base metal, which is compatible with the mist refueling method ,
The reamer is provided with an oblique groove on the outer peripheral surface so as to extend inclined with respect to the rotation axis, and the oblique groove accommodates the super-hard chip,
An inclination angle formed by the oblique groove with respect to the rotation axis is −3 ° to −15 °,
There is no guide pad ,
The ultra-hard chip is provided with a flank and a rake face, and is provided with a hole opened in a reamer surface for supplying mist to the rake face side and the flank face side,
A method of processing a workpiece using a reamer, wherein mist is supplied from a hole on the rake face side to a surface of the workpiece immediately before being processed with the ultra-hard chip. When viewed from the reamer tip side, the angle formed between the line connecting the opening of the rake face side hole and the rotation axis and the line connecting the opening of the hole on the flank face side and the rotation axis is 45 ° or less. A method for machining a workpiece using the reamer according to claim 1 . Both the rake face side hole and the flank face side hole extend linearly in the vicinity of the reamer surface, and the direction in which the rake face side hole extends is 15 ° or more and 45 ° with respect to the rotation axis. The following angle is formed, and an angle of 20 ° or more and 30 ° or less when viewed from the front end side with respect to the front cutting edge of the rake face,
The extending direction of the hole on the flank side forms an angle of 15 ° or more and 45 ° or less with respect to the rotation axis, and 45 ° or more and 60 ° when viewed from the front end side with respect to the front cutting edge of the rake face. The processing method of the workpiece using the reamer according to claim 1 or 2 , wherein an angle of less than or equal to ° is formed . The workpiece processing method using a reamer according to any one of claims 1 to 3 , wherein a material of the workpiece processed by the reamer is a non-ferrous metal material .