WO2008038560A1

WO2008038560A1 - Substitute edge of cutting tool

Info

Publication number: WO2008038560A1
Application number: PCT/JP2007/068252
Authority: WO
Inventors: Tetsuro Mantani; Narihito Tanaka; Terutoshi Tsunashima; Terumi Sakakida
Original assignee: Kanefusa Kabushiki Kaisha
Priority date: 2006-09-27
Filing date: 2007-09-20
Publication date: 2008-04-03
Also published as: JPWO2008038560A1; JP5095621B2

Abstract

Substitute edge (1) consisting only of chip (1a) cut out from a sintered blank having ultrahigh-hardness sintered layer (2) and sintered hard alloy layer (3). The chip (1a) is cut out from the sintered blank so that the ultrahigh-hardness sintered layer (2) lies on the reverse side of edge (1c). Cutting edge (2a) is formed at the apical end rim of the chip (1a). On the reverse side of edge (1c) of the chip (1a), there is provided groove (2b) extending in the direction of edge length of the cutting edge (2a).

Description

Specification

Replacement blade for cutting tools

Technical field

[0001] The present invention relates to a blade for a cutting tool used for wood processing and processing similar to wood processing. In particular, the present invention relates to a cutting blade for a cutting tool comprising a chip having an ultra-high hardness sintered layer excellent in wear resistance.

Background art

Conventionally, a replaceable blade composed of a chip having an ultra-high hardness sintered layer is disclosed in, for example, FIGS. 2c, 2d, and 4 of Japanese Utility Model Laid-Open No. 7-17505 (505 gazette). The replaceable blade disclosed in FIG. 2 of the 505 gazette is composed of a chip cut from a sintered blank having two layers of an ultra-high hardness sintered layer and a cemented carbide layer. It was arranged on the cutting edge side, and the cemented carbide layer was arranged on the base end side. The replaceable blade disclosed in FIG. 4 of 505 gazette is a method of brazing a sintered blank having two layers of a super-hard sintered layer and a cemented carbide layer to a steel base metal. It was composed of chips cut from a lump consisting of An ultra-high hardness sintered layer was arranged on the cutting edge side, and a cemented carbide layer and a steel base metal were arranged in this order toward the base end side. Therefore, in these replacement blades, the interface between the ultra-hard sintered layer and the cemented carbide layer is substantially parallel to the cutting direction. For this reason, a shearing force is applied to the boundary surface during cutting, which causes the problem that the ultra-high hardness sintered layer is easily peeled off from the ultra-high hardness sintered layer.

[0003] A replaceable blade 20 shown in FIG. 8 is also conventionally known. The replaceable blade 20 has a tip 21 composed of an ultra-high hardness sintered layer 22 and a cemented carbide layer 23, and a steel body 24 that holds the tip 21. The chip 21 was brazed to the stepped step portion 24a of the steel body 24 so that the ultra-high hardness sintered layer 22 was on the blade back side. Accordingly, the boundary surface between the ultra-high hardness sintered layer 22 and the cemented carbide layer 23 has an angle of at least 60 ° with respect to the cutting direction, and it is difficult to apply a shearing direction force to the boundary surface. For this reason, the ultra-high hardness sintered layer 22 was configured to be difficult to separate from the cemented carbide layer 23. This type of replaceable blade is also a relatively large replaceable blade, which is significantly different in configuration from a replaceable blade consisting of only chips. The replaceable blade 20 shown in FIG. The step 24a for the chip is formed on the steel body 24, and the chip 21 is brazed to the step 24a, so that the chip 21 on the back of the blade and the steel body 24 need to be flush with each other. Has the problem of becoming.

Disclosure of the invention

Problems to be solved by the invention

[0004] Accordingly, the present invention provides a cutting blade for a cutting tool that has a structure in which an ultra-high hardness sintered layer is difficult to peel off from a cemented carbide layer and that does not require brazing of a tip to a steel body or the like. The issue is to provide.

Means for solving the problem

[0005] The replaceable blade of the present invention is composed only of a chip cut out from a sintered blank provided with a super-hard sintered layer and a cemented carbide layer. The tip is cut from the sintered blank so that the back side of the blade becomes a super-hard sintered layer, and a cutting edge is formed on the tip edge of the tip. Characterized by the formation of a groove extending to

[0006] Accordingly, since the replaceable blade is composed only of a chip cut out from a sintered blank, it is not necessary to braze the chip to a steel body or the like. In addition, since the ultra-high hardness sintered layer is located on the back side of the blade, the interface between the ultra-hard sintered layer and the cemented carbide layer has an angle of at least 60 ° with respect to the cutting direction. It will have a state. For this reason, the ultra-high hardness sintered layer is difficult to peel off from the cemented carbide layer during cutting. Further, since the replaceable blade has a groove, the replaceable blade can be prevented from jumping out of the cutter body by the groove.

[0007] By the way, the chip is cut out from a sintered blank including an ultra-high hardness sintered layer and a cemented carbide layer, and the sintered blank is sintered under high temperature and high pressure. Therefore, internal stress may remain in the chip due to the difference in thermal expansion coefficient between the ultra-high hardness sintered layer and the cemented carbide layer, and the chip may be warped. In contrast, the replaceable blade of the present invention has a groove, and the warpage of the chip can be reduced by reducing the internal stress of the chip by the groove. Therefore, the groove has not only the function of preventing the cutter body from jumping out, but also the function of reducing chip warpage. [0008] The invention can also have a cutting edge at both end edges and a groove at a substantially intermediate position between the both end edges. Therefore, after the cutting edge at one end edge is worn, the cutting edge at the other end edge can be used by inverting the replacement blade.

Brief Description of Drawings

[0009] Fig. 1 is a side view of a replaceable blade.

FIG. 2 is a front view from the direction of arrow II in FIG.

FIG. 3 is a side view of the rotary blade and the replacement blade with the replacement blade attached to the rotary blade.

FIG. 4 is a perspective view of a sintered blank.

FIG. 5 is a part of a side view of a strip-shaped cut piece cut out from the sintered blank of FIG.

FIG. 6 is a front view of a replaceable blade according to the second embodiment.

FIG. 7 is a side view of a rotary blade and a replacement blade according to Embodiment 3.

FIG. 8 is a perspective view of a conventional replaceable blade.

BEST MODE FOR CARRYING OUT THE INVENTION

[0010] (Embodiment 1)

Embodiment 1 will be described with reference to FIGS. The replaceable blade 1 is a replaceable blade for cutting tools similar to wood processing and wood processing, and has two layers of a super-hard sintered layer 2 and a cemented carbide layer 3 as shown in FIG. . The ultra-high hardness sintered layer 2 is made of polycrystalline diamond (PCD), polycrystalline cubic boron nitride (PCBN), etc., and has excellent wear resistance.

[0011] In the manufacturing method of the replaceable blade 1, first, as shown in FIG. 4, a mixture obtained by mixing particles such as diamond and metal powder as a binder phase is press-molded to obtain an ultra-high hardness sintered layer 12. Cemented Carbide A mixture of hard phase powder and binder phase metal powder is pressed to obtain a cemented carbide layer 13. Next, the ultra-hard sintered layer 12 and the cemented carbide layer 13 are sintered under high pressure and high temperature, for example, 40,000 atm and 1400 ° C under high pressure and high temperature. (Consolidated material) 11 is formed. Then, the sintered blank 11 is cut to obtain a strip-shaped cut piece 11a shown in FIG.

[0012] Next, as shown in FIG. 5, the chip la is cut out from the strip-shaped cut piece 11a. The chip la has a trapezoidal cross section, and is cut from the sintered blank 11 so that the short side is the cemented carbide layer 3 and the long side is the ultra-high hardness sintered layer 2. Therefore the tip la is bladed as shown in Figure 1 The back surface has an ultra-hard sintered layer 2 on the lc side and a cemented carbide layer 3 on the blade surface lb side.

Next, as shown in FIG. 5, a groove 2b is formed in the chip la. As shown in FIG. 2, the groove 2b is formed at a substantially central position in the short direction of the ultra-high hardness sintered layer 2 using a wire cut electric discharge machining method or the like. The groove 2b extends over the entire length in the longitudinal direction of the ultra-high hardness sintered layer 2 and penetrates both edges. As shown in FIG. 1, the depth of the groove 2b is almost the same as the thickness of the ultra-high hardness sintered layer 2, and is, for example, 70% to 100% of the thickness of the ultra-high hardness sintered layer 2. Alternatively, the thickness of the ultra-high hardness sintered layer 2 is not less than 10% and not more than 12%, and penetrates the ultra-high hardness sintered layer 2 to reach the cemented carbide layer 3! /.

Next, as shown in FIGS. 1 and 2, sharp cutting edges 2a are formed at both lateral edges of the tip la. The cutting edges 2a are formed at both end edges of the ultra-high hardness sintered layer 2 by grinding both end faces, which are cut faces when cut from the sintered blank 11. Therefore, the replaceable blade 1 has the cutting edges 2a at both ends, and has a groove 2b at a substantially intermediate position between the pair of cutting edges 2a.

[0015] The ultra-high hardness sintered layer 2 of the replaceable blade 1 has a thickness of about 0.5 mm, and the cemented carbide layer 3 has a thickness of 1.5 mm or more. Therefore, the replaceable blade 1 is improved in handleability with the overall thickness being increased by the cemented carbide layer 3.

As shown in FIG. 3, the replaceable blade 1 is used by being detachably attached to, for example, a rotary blade 10. The rotary blade 10 has a substantially disc-shaped cutter body 4, a back seat 5 provided in an outer peripheral opening 4 a of the cutter body 4, and a bolt 6 for pushing the back seat 5. A plurality of outer peripheral openings 4 a are formed at predetermined intervals on the outer peripheral portion of the cutter body 4. The backing 5 has a ridge 5a that fits into the groove 2b of the replaceable blade 1. When the ridge 5a is fitted into the groove 2b, the replaceable blade 1 jumps out of the cutter body 4 by centrifugal force. To prevent that. The bolt 6 is screwed into the rotating rear wall of the outer peripheral opening 4 a of the cutter body 4, and the replacement blade 1 is fixed to the cutter body 4 by pressing the replacement blade 1 through the back seat 5.

[0017] The first embodiment is formed as described above. That is, the replaceable blade 1 is composed only of a chip 1 a cut out from a sintered blank 11 having an ultra-high hardness sintered layer 2 and a cemented carbide layer 3 as shown in FIG. The chip la is cut from the sintered blank 11 so that the back surface lc side of the blade is the ultra-hard sintered layer 2, and a cutting edge 2a is formed at the tip edge of the chip la, and the cutting edge is formed on the back surface lc of the chip la. A groove 2b extending in the blade length direction of 2a is formed. [0018] Accordingly, since the replaceable blade 1 is composed only of the chip la cut out from the sintered blank 11, it is not necessary to braze the chip la to a steel body or the like. In addition, since the ultra-high hardness sintered layer 2 is located on the back surface lc side of the replaceable blade 1, the boundary surface between the ultra-high hardness sintered layer 2 and the cemented carbide layer 3 is cut as shown in Fig. 3. It will have an angle of at least 60 ° to the direction. For this reason, the ultra-high hardness sintered layer 2 is difficult to peel off from the cemented carbide layer 3 during cutting. Further, since the replaceable blade 1 has the groove 2b, the replaceable blade 1 can be prevented from jumping out of the cutter body 4 by the groove 2b.

Further, as shown in FIG. 1, the replaceable blade 1 reduces the internal stress remaining in at least one of the ultra-hard sintered layer 2 and the cemented carbide layer 3 by the groove 2b, thereby reducing the warping of the chip la. It is configured to do this. By the way, the chip la is cut out from the sintered blank 11 including the ultra-high hardness sintered layer 12 and the cemented carbide layer 13 as shown in FIG. 4, and the sintered blank 11 is sintered under high temperature and high pressure. . Therefore, internal stress may remain in the chip la due to a difference in thermal expansion coefficient between the ultra-high hardness sintered layer 12 and the cemented carbide layer 13, and the chip la may be warped. On the other hand, the replaceable blade 1 has a groove 2b. By reducing the internal stress of the chip la by the groove 2b, the warp of the chip la can be reduced. Therefore, the groove 2b has not only a function of preventing the protrusion from the cutter body 4 but also a function of reducing the warping of the chip la.

In addition, as shown in FIG. 1, the replaceable blade 1 has a cutting edge 2a at both end edges and a groove 2b at a substantially middle position between both end edges. Therefore, after the cutting edge 2a at the one end edge is worn, the cutting edge 2a at the other end edge can be used by reversing the replacement blade 1.

The replacement blade 1 can also be regenerated by re-grinding the cutting edge 2a after the pair of cutting edges 2a are worn. That is, the replaceable blade 1 can regenerate the cutting edge 2a by regrinding the end face in the short direction, which is a cut surface when cut from the sintered blank 11 as shown in FIG. Therefore, compared to the case where the back surface lc side of the blade is re-polished, the polishing amount of the ultra-high hardness sintered layer 2 having high hardness is small and the structure is easy to polish. In addition, the area gripped by the polishing machine is wider than the case where the back side of the blade lc side is re-polished! Also, since the groove 2b is not formed on the surface to be polished, if the groove 2b becomes shallow by polishing! /, No problem will occur! /.

[0022] (Embodiment 2) The second embodiment will be described with reference to FIG. In the second embodiment, the shape of the force cutting edge 2c formed in substantially the same manner as in the first embodiment is different from the shape of the cutting edge 2a shown in FIG. Hereinafter, the second embodiment will be described focusing on the differences.

As shown in FIG. 6, the replaceable blade 1 according to Embodiment 2 has cutting edges 2c at both ends in the short direction, and has a groove 2b at an intermediate position between the pair of cutting edges 2c. The cutting blade 2c has linear portions 2cl extending parallel to the longitudinal direction of the replaceable blade 1 on both the left and right sides, and has a notch portion 2c2 between these linear portions 2cl. The notch 2c2 is formed in a V shape, a U shape, or a curved surface depending on the desired edge processing. The groove 2b extends in the blade length direction (the left-right direction in FIG. 6) of the cutting blade 2c.

[Embodiment 3]

The third embodiment will be described with reference to FIG. The third embodiment is formed in substantially the same manner as the first embodiment, but differs from the first embodiment in that the groove 3a is provided on the cemented carbide layer 3 side. Hereinafter, Embodiment 3 will be described focusing on the differences.

As shown in FIG. 7, the replaceable blade 1 according to Embodiment 3 has a groove 3 a in the cemented carbide layer 3 on the blade surface lb side. The groove 3a extends in the blade length direction at a substantially middle position between the pair of cutting blades 2a. Convex ridges 4c are formed on the rotation rear wall surface of the outer peripheral opening 4a of the cutter body 4 facing the groove 3a. The protrusion 4c is fitted into the groove 3a to prevent the replaceable blade 1 from jumping out of the cutter body 4 due to centrifugal force.

The present invention is not limited to the embodiments;! To 3, and may be the following embodiments. For example, the spare blades of Embodiments 1 to 3 are constituted by chips cut from a sintered blank having only two layers of a super-hard sintered layer and a cemented carbide layer. In addition to these two layers, the replacement blade may be formed only from a chip cut from a sintered blank provided with another layer.

[0027] The replaceable blades of Embodiments 1 to 3 have a configuration having cutting edges at both end edges. However, it may be configured to have a cutting edge only at one edge.

[0028] The replacement blades of Embodiments 1 to 3 are configured to have cutting blades at both edges in the short direction.

It may be a replaceable blade that has a reverse force in the lateral direction and the length in the short direction, and a replaceable blade having cutting edges at both ends in the longitudinal direction.

[0029] The grooves formed in the replaceable blades of Embodiments 1 to 3 cut through both longitudinal edges of the replaceable blade. It was. However, the groove may extend in the longitudinal direction and may not be cut off at both ends in the longitudinal direction.

Claims

The scope of the claims

[1] A replacement blade for a cutting tool,

It consists only of a chip cut out from a sintered blank having a super-hard sintered layer and a cemented carbide layer, and the chip is cut out from the sintered blank so that the blade back side becomes the ultra-hard sintered layer and A blade for a cutting tool, wherein a cutting edge is formed at a tip edge of the tip, and a groove extending in a blade length direction of the cutting blade is formed on a back surface or a blade surface of the tip.

[2] A replaceable blade of the cutting tool according to claim 1,

A replacement blade for a cutting tool having a cutting edge at both end edges and a groove at a substantially middle position between the both end edges.

[3] A replaceable blade of the cutting tool according to claim 1,

The ultra-high hardness sintered layer is a replacement blade for a cutting tool which is a polycrystalline diamond sintered layer.