JP2015093347A - Rotary tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary tool for hole drilling which can efficiently remove chips and is capable of hole drilling with a high accuracy.SOLUTION: A rotary tool in which axially extending groove and cutting edge are provided at a tip of a shaft-shaped base metal, and the groove is provided with an opening. The opening is continuous with an open hole axially provided at a central part of the shaft-shaped base metal, plural openings are present and holes for connecting the plural openings are provided. The open hole has a direction changed to an outer peripheral direction of the shaft-shaped base metal in the middle of approaching a rear end side of the shaft-shaped base metal, and opens on the outer periphery of the base metal. Further, a cutting rotary tool having a super hard tip, which comprises a super hard sintered body at a tip of the groove and is provided with a cutting edge, is configured.

Description

  The present invention relates to a rotary tool for machining a hole, and more particularly to a rotary tool suitable for finishing a blind hole formed in an aluminum alloy part.

  For example, as an example of an aluminum alloy part, there is a valve body which is a part of an automatic transmission for automobiles, and a rotary cutting tool having a diamond sintered body (PCD) cutting edge tip is used for finishing a spool hole of the valve body. Is used.

In general, chips during processing by a rotary cutting tool are scattered and discharged together with coolant supplied for cooling and lubrication. The coolant mixed with chips is removed by passing through a filter, or collected by a chip conveyor or the like provided in the processing facility.
Further, as a method of collecting chips on the tool side, there is a method of sucking chips from the outside adopted in a milling machine or a hole saw. In this method, a cover-like object is provided around the tool, and chips scattered in the cover are sucked.

  However, the spool hole of the valve body may be a blind hole, or even if it is a through-hole, there is an oil passage that crosses the hole, so there are intermittent machining parts, and the removal allowance is short Therefore, a chip flow similar to a blind hole may occur. Due to such a hole shape, the chips are difficult to be discharged from the machining hole, and the chips remaining in the machining hole are caught in the oil passage, the sharpness of the tool is lowered and the machining surface is deteriorated, or the machining surface is damaged. Problems such as entering are likely to occur.

  As an example of a rotary cutting tool that solves such a problem, there is a reamer in which a cutting edge chip has a chip break function. (For example, see Patent Document 1)

JP 2007-130750 A

  However, the processing of spool holes in the valve body as described above has recently been required to be highly efficient, and in many cases, the shape of the hole has become complicated as the valve body becomes more sophisticated. However, the requirements cannot be satisfied, and it has become an issue how to efficiently remove chips in terms of machining accuracy, tact time, and cost.

  For this reason, the present invention provides a rotary tool capable of efficiently removing chips and enabling high-precision drilling even in a hole such as a blind hole in which chips are difficult to be discharged.

  The first feature of the rotary tool of the present invention is that an axially extending groove and a cutting edge are provided at the tip of a shaft-shaped base metal, and an opening is provided in the groove.

  According to the rotary tool having such a configuration, chips generated at the cutting edge portion provided at the tip of the shaft-shaped base metal during processing are formed in a groove extending in the axial direction at the tip of the shaft-shaped base metal. Then, the chips flow into the opening, so that the chips are discharged smoothly.

  Moreover, it is preferable that the said opening part is continued with the through-hole provided in the axial direction in the center part of the said axial base metal.

  According to the rotary tool having such a configuration, the chips flowing into the opening flow into the through hole provided in the axial direction in the central portion of the shaft-shaped base metal, and the chips are directed toward the rear end side of the base metal. Easily discharged.

  The rotary tool as described above preferably has a configuration in which a super hard tip is provided at the end of the groove and a cutting edge is provided on the super hard tip.

  Further, it is preferable that a plurality of the openings are provided, and a hole connecting the plurality of openings is provided.

  According to the rotary tool having such a configuration, the chips generated at the cutting edge portion flow into the plurality of openings, and then flow into the holes connecting the plurality of openings. Since it flows into the through-hole provided in the axial direction in the central part of gold, chips are discharged smoothly.

  And it is preferable that the said through-hole changes the direction in the outer peripheral direction of the said shaft-shaped base metal in the middle toward the rear end side of the said shaft-shaped base metal, and opens to the outer periphery of the said base metal.

  According to the rotary tool having such a configuration, the chips flowing through the through hole provided in the axial direction in the center portion of the shaft-shaped base metal come out of the workpiece on the rear end side of the base metal. Since it can discharge | emit from the part which exists, a chip will not flow into a cutting blade part again.

  In such a rotary tool, the effect of the present invention can be greatly obtained when the super hard tip is a super hard sintered body and is a rotary cutting tool.

  Further, the rotary tool having the above-described configuration is very effective when used for processing a blind hole.

  According to the rotary tool of the present invention, even a hole such as a blind hole in which chips are difficult to be discharged can be efficiently processed with high accuracy.

It is a figure which shows the 1st example of the rotary tool of this invention, (a) is a front view, (b) is an enlarged left view. 2A and 2B are cross-sectional views illustrating a cross-section of FIG. 1, in which FIG. 1A is a cross-sectional view taken along line BB in FIG. 1B, and FIG. It is a fragmentary perspective view which shows the front end side of the rotary tool of FIG. It is a figure which shows the 2nd example of the rotary tool of this invention, (a) is a front view, (b) is an enlarged left view. 5A is a cross-sectional view showing a cross section of FIG. 4, and FIG. 4A is a cross-sectional view taken along the line DD of FIG. 4B, and FIG. 5B is an enlarged cross-sectional view taken along the line CC of FIG. It is a fragmentary perspective view which shows the front end side of the rotary tool of FIG. It is a figure which shows the 3rd example of the rotary tool of this invention, (a) is a front view, (b) is an enlarged left view. 8A is a cross-sectional view showing a cross-section of FIG. 7, and FIG. 7A is a cross-sectional view taken along line FF in FIG. 7B, and FIG. 7B is an enlarged cross-sectional view taken along line E-E in FIG.

  The 1st example of the rotary tool of this invention is shown in FIG.1, FIG.2 and FIG.3. 1A is a front view showing a rotary tool of the present invention, FIG. 1B is an enlarged left side view, FIG. 2A is a cross-sectional view taken along line BB in FIG. 1B, and FIG. FIG. 3 is an AA enlarged sectional view of FIG. 1A, and FIG. 3 is a partial perspective view showing the tip side of the rotary tool of the present invention.

  Referring to FIGS. 1, 2 and 3, a rotary tool 1 according to the present invention includes a groove 3 (3a) extending in the axial direction on the distal end side of a shaft-shaped base metal 2 made of cemented carbide or carbon steel. And 3b) are provided at equal intervals in the circumferential direction. A thin portion is provided on the tip side of the groove 3, and an ultra-hard chip 4 made of an ultra-hard sintered body such as a diamond sintered body (PCD) or a cubic boron nitride sintered body (PCBN) is provided in the thinned portion. Joined by brazing. A tip cutting edge 5a is provided at the boundary between the rake face 4a of the superhard tip 4 and the flank face 4b facing the tip side, and an outer peripheral cutting edge 5b is provided at the boundary between the rake face 4a and the flank face 4c facing the outer peripheral side. Is provided.

  Referring to FIGS. 2 and 3, a coolant supply hole 9 penetrating from the rear end side toward the front end side is provided on the side near the outer periphery inside the base metal 2, and is opened at the front end of the base metal 2. doing. The coolant supply hole 9 is for supplying coolant to the super hard tip 4 when processing. A through hole 8 is provided near the axis of the base metal 2 from the rear end side to the front end side. Of the two grooves 3a and 3b, openings 6a and 6b are respectively provided on the rear end side of the position where the super hard chip 4 is provided, and a hole 7 is provided to connect these openings 6a and 6b. Furthermore, the openings 6a and 6b are connected to the through-hole 8 through the hole 7, and a discharge hole 10 is provided on the rear end side of the through-hole 8 so as to change the direction from the axial direction to the outer peripheral side and open to the outer periphery. It has been.

  In the rotary tool 1 having such a structure, when drilling, the coolant is supplied to the front end side through the coolant supply hole 9 and the machining is performed by the super hard tip 4. Chips generated in the super-hard chip 4 flow from the opening 6 to the hole 7 through the groove 3 together with the coolant, and are discharged to the outside through the through hole 8 and the discharge hole 10. For this reason, the amount of chips flowing into the outer peripheral cutting edge 5b and winding around the cutting edge 5 is greatly reduced, and high-precision drilling is possible.

  Next, the 2nd example of the rotary tool of this invention is shown in FIG.4, FIG.5 and FIG.6. 4 (a) is a front view showing the rotary tool of the present invention, FIG. 4 (b) is an enlarged left side view, FIG. 5 (a) is a DD cross-sectional view of FIG. 4 (b), and FIG. FIG. 4A is an enlarged cross-sectional view taken along the line C-C in FIG. 4A, and FIG.

  4, 5, and 6, a rotary tool 11 according to the present invention includes a groove 13 (13 a) extending in the axial direction on the distal end side of a shaft-shaped base metal 12 made of cemented carbide or carbon steel. , 13b and 13c) are provided at equal intervals in the circumferential direction. A thin portion is provided on the tip side of the groove 13, and an ultra-hard chip 14 made of an ultra-hard sintered body such as a diamond sintered body (PCD) or a cubic boron nitride sintered body (PCBN) is provided in the thinned portion. Joined by brazing. A tip cutting edge 15a is provided at the boundary between the rake face 14a and the flank face 14b facing the tip side of the super-hard chip 14, and an outer peripheral cutting edge 15b is provided at the boundary between the rake face 14a and the flank face 14c facing the outer peripheral side. Is provided.

  Referring to FIGS. 5 and 6, a coolant supply hole 19 that penetrates from the rear end side to the front end side is provided on the side near the outer periphery inside the base metal 12, and is opened at the front end of the base metal 12. doing. The coolant supply hole 19 is used for supplying coolant to the portion of the super-hard chip 14 during processing. Further, a through hole 18 is provided near the axis of the base metal 12 from the rear end side to the front end side. Of the three grooves 13a, 13b, and 13c, openings 16a, 16b, and 16c are provided on the rear end side from the position where the super-hard chip 14 is provided, and a hole 17 that connects these openings 16 is provided. It has been. Further, the openings 16a, 16b and 16c are connected to the through hole 18 through the hole 17, and the rear end side of the through hole 18 changes the direction from the axial direction to the outer peripheral side and opens to the outer periphery. Is provided.

  The rotary tool 11 having such a structure can obtain the same effect as the rotary tool of the first example.

  7 and 8 show a third example of the rotary tool of the present invention. 7 (a) is a front view showing the rotary tool of the present invention, FIG. 7 (b) is an enlarged left side view, FIG. 8 (a) is an FF sectional view of FIG. 7 (b), and FIG. 8 (b). FIG. 9 is an EE enlarged sectional view of FIG.

  The rotary tool of the third example has the same shape as that of the rotary tool of the first example, and opens to the outer periphery at the rear end side of the through hole 8 provided near the axis of the base metal 2. The point from which the discharge hole 10 is provided diagonally with respect to the axial center differs from a 1st example.

  In the rotary tool 1 having this structure, the discharge hole 10 is on the rear end side as the outer peripheral side is reached, and the chips flowing through the through hole 8 can easily flow into the discharge hole 10 smoothly. In addition to the same effect as that of the rotary tool, an effect that chips are more easily discharged can be obtained.

  The rotary tool of the present invention and a conventional rotary tool were manufactured for comparison, and a cutting test of a pilot hole in the shape of a blind hole that was previously drilled was performed. As the rotary tool of the present invention, the tool shown in FIGS. 1, 2 and 3 described above was manufactured. Further, as the conventional rotary tool, the openings 6a and 6b, the hole 7 connecting the openings 6a and 6b, the through hole 8 and the discharge hole 10 are not provided, and other specifications and shapes are the same as those of the rotary tool of the present invention. A rotating tool was produced.

  As a result of performing a cutting test using these rotary tools, as for the rotary tool of the present invention, about 70 to 80% of the chips pass from the openings 6a and 6b through the hole 7 and the through hole 8, and the discharge hole 10 is obtained. It is discharged together with the coolant, and there is no scratch on the machined surface, and it can be machined to the required machining accuracy, whereas the conventional rotary tool has scratches that seem to be formed by chips, It could not be processed to the required processing accuracy.

  The rotary tool of the present invention can be applied not only to the reamer described in the above embodiment but also to various rotary cutting tools such as a milling cutter and an end mill, and a rotary tool having a superabrasive layer as a cutting edge instead of a super hard chip. .

1, 11 Reamer 2, 12 Base metal 3, 13 Groove 4, 14 Super hard tip 5, 15 Cutting edge 5 a, 15 a Tip cutting edge 5 b, 15 b Outer peripheral cutting edge 6, 16 Opening 7, 17 Hole 8 connecting the opening , 18 Through holes 9, 19 Coolant supply holes 10, 20 Discharge holes

Claims (8)

A groove and a cutting edge extending in the axial direction are provided at the tip of the shaft-shaped base metal,
A rotary tool in which an opening is provided in the groove.   The rotary tool according to claim 1, wherein the opening is continuous with a through-hole provided in an axial direction in a central portion of the shaft-shaped base metal.   The rotary tool according to claim 1, wherein a super hard tip is provided at a tip of the groove, and a cutting edge is provided on the super hard tip.   The rotary tool according to any one of claims 1 to 3, wherein a plurality of the openings are provided, and a hole connecting the plurality of openings is provided.   The said through-hole changes direction in the outer peripheral direction of the said shaft-shaped base metal in the middle toward the rear end side of the said shaft-shaped base metal, and opens to the outer periphery of the said base metal. The rotary tool according to item.   The rotary tool according to claim 1, wherein the ultra-hard chip is an ultra-hard sintered body.   It is a rotary cutting tool, The rotary tool of any one of Claims 1-6.   The rotary tool according to any one of claims 1 to 7, which is used for processing a blind hole.

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