JP6033072B2 - Cutting tool and method for regrinding the cutting tool - Google Patents

Description

  The present invention relates to a cutting tool having blade portions such as a milling cutter, a hob, a broach, and a reamer, and a method for regrinding the cutting tool.

  Conventionally, the cutting tool as described above has a blade portion whose cutting edge is the intersection line where the rake face and the flank face intersect, and the cutting edge cuts a predetermined portion of a workpiece (workpiece) to be cut. Then, the workpiece is formed into a desired shape.

  The cutting blade has a high hardness for cutting a predetermined portion of the workpiece, and a coating layer is formed by depositing TiCN (titanium carbonitride), TiAlN (titanium nitride aluminum) or the like on the surface as necessary. Is given.

  However, if the workpiece is repeatedly cut, the cutting edge is naturally worn and the cutting performance deteriorates. For this reason, in order to make the cutting performance of the cutting tool suitable for use again, it is often performed to regrind the blade portion.

  For example, in the throw-away tip re-polishing apparatus described in Patent Document 1, the tip is fixed on an indexing table, and re-grinding is performed by projecting a polishing liquid onto the tip.

  Also, a cutter polishing apparatus for a gear cutter described in Patent Document 2, a hob blade-attached board for a hob used for manufacturing a gear described in Patent Document 3, a gear described in Patent Document 4, and the like Re-grinding operations are also performed in the broach grinding apparatus for broaches used for drilling metal parts and the cutting tool grinding apparatus for broaching tools described in Patent Document 5.

  Furthermore, in the polishing mechanism of the rotary tool described in Patent Document 6, regrind is performed by bringing a piece to be ground into contact with the rake face side close to the cutting edge portion of the reamer. Also in the method for polishing a rotary tool described in Patent Document 7, regrind is performed by filling a resin filling material into a reamer chip discharging groove. And in the solid carbide hob for generating and cutting gear teeth described in Patent Document 8, the material is composed of a cemented carbide and the number of cutting edge grooves is 16-30. This eliminates the need for blade killing and facilitates blade mounting and regrinding.

JP 2010-149241 A Japanese Patent Publication No.8-18231 Japanese Patent No. 3113918 Japanese Patent No. 4870593 Japanese Patent Laid-Open No. 7-9308 Japanese Patent Laid-Open No. 5-228809 JP-A-6-170705 Japanese Patent Laid-Open No. 10-146720

  When the above-mentioned coating is applied to the cutting edge, the re-grinding removes the coating, and it becomes necessary to perform a re-coating step after re-grinding. However, the re-coating process has a problem that the cost increases, and this re-coating process may be omitted when the cost is important. Then, the problem that the lifetime of a cutting tool will fall remarkably will arise this time.

  Further, the wear of the cutting edge becomes abnormally large during the cutting process, making it impossible to use as a cutting tool, or the accuracy of the work may be lowered and become defective.

  Further, in the conventional configuration, since it is necessary to form a new cutting edge each time re-grinding, the work time becomes long and skill may be required.

  Then, an object of this invention is to provide the cutting tool which can solve the said problem, and the re-grinding method of this cutting tool.

  The present invention includes a cutting tool having a cutting edge whose cutting edge is the intersection line where the rake face and the flank face intersect, and the cutting edge can be used repeatedly by regrinding the rake face of the cutting edge. In the above, the flank is provided with a preliminary groove that is recessed along the cutting line direction of the cutting edge, and further, a groove at a position far from the rake face among the groove edges on both sides of the preliminary groove. The edge is formed in the same shape as the cutting edge, so that the groove edge is a preliminary cutting edge, and the inner peripheral surface of the preliminary groove that is coupled to the preliminary cutting edge is a preliminary rake face portion. The cutting tool is characterized in that the preliminary cutting edge is made a new cutting edge by re-grinding to a position continuous with the preliminary rake face portion.

  By adopting the above configuration, when regrinding, it is sufficient to grind from the cutting edge used so far to the place where the preliminary cutting edge formed next to the cutting edge is continuous with the rake face. Therefore, since the regrinding operation can be performed using the preliminary groove as an index, the regrinding operation is extremely simple. In addition, the above configuration can prevent abnormal wear of the cutting blade during the cutting process, and can be disabled as a cutting tool, or the accuracy of the work can be reduced and become defective. Can be prevented.

  Furthermore, it is preferable that the blade portion is made of a metal material, and the coating layer is continuously formed on the surfaces of the cutting edge and the preliminary cutting edge of the blade portion.

  In such a configuration, since a coating layer is formed in advance on the surface that has become a new cutting edge by re-grinding, a process of forming a separate coating on the new cutting edge as in the past is executed. There is no need to do. For this reason, it is possible to avoid an increase in cost and to appropriately ensure the tool life of the cutting tool.

  Furthermore, a configuration is proposed in which a plurality of preliminary grooves are arranged in the regrinding direction of the blade portion.

  By setting it as the said structure, a preliminary | backup cutting blade can be reused as a cutting blade in multiple times.

  Furthermore, the inner peripheral surface that faces the inner peripheral surface on which the preliminary rake face portion is formed, with the groove bottom of the preliminary groove as a reference, may be configured as an inclined surface that moves away from the rake face toward the groove bottom. .

  By adopting the above configuration, at least the strength in the cutting direction of the portion where the preliminary cutting edge is formed is sufficiently secured, and it is possible to stably perform the cutting operation using the preliminary cutting edge as a new cutting edge. Become.

  Furthermore, a configuration is proposed in which the groove bottom shape of the preliminary groove is a round bottom shape convex in the groove depth direction.

  With this configuration, when a new rake face is formed starting from the groove bottom of the preliminary groove, if the groove bottom has a so-called R shape, the error in the position of the rake face at the groove bottom is absorbed to some extent. In addition, there is an advantage that the grinding accuracy is suitably relaxed. Further, it is possible to prevent the stress from concentrating on the groove bottom and causing cracks and the like.

  In addition, the present invention can repetitively use the cutting edge by re-grinding the rake face of the cutting edge with respect to a cutting tool having a cutting edge whose cutting edge is the intersection line where the rake face and the flank face intersect. In the re-grinding method of the cutting tool, a preliminary groove is formed in the flank along the cutting line direction of the cutting edge, and the groove surface on both sides of the preliminary groove, with respect to the rake face The groove edge at a distant position has the same shape as the cutting edge, the groove edge serves as a spare cutting edge, and the inner peripheral surface of the spare groove coupled to the spare cutting edge serves as a spare rake face, and the rake face serves as the spare blade. A re-grinding method for a cutting tool, characterized in that the preliminary cutting edge is made a new cutting edge by re-grinding to a position continuous with the rake face portion.

  With this configuration, the rake face can be re-ground using the preliminary groove as an index, and the pre-shaped pre-cutting blade can be used as a new cutting edge, so re-grinding can be performed without requiring skill. It becomes.

  In the cutting tool of the present invention, since the preliminary cutting edge is already formed at the time of manufacture, the cutting accuracy and cutting ability of the cutting tool do not decrease after re-grinding.

  Further, the regrinding method of the cutting tool of the present invention can use a pre-cutting blade that is not yet worn while using the pre-groove as an index by re-grinding. There is an effect.

It is explanatory drawing which shows the use condition of the cutting tool concerning 1st Embodiment. The blade part of the cutting tool concerning 1st Embodiment is shown, (a) is a front view, (b) is the sectional view on the AA line of (a), (c) is a rear view, (d) is a top view, (E) is the BB line cross-section partial enlarged view of (a). It is a figure explaining the re-grinding process of the blade part of the cutting tool concerning a 1st embodiment, (a) is a sectional view showing the state before re-grinding, (b) is a sectional view showing the state after re-grinding, (C) is an enlarged front view showing a state after re-grinding. It is a cutting tool concerning 2nd Embodiment, (a) is a front view, (b) is a side view, (c) is the elements on larger scale of a blade part, (d) is the blade part seen from the rake face side. It is explanatory drawing. It is the cutting tool concerning 3rd Embodiment, Comprising: (a) is a side view, (b) is the elements on larger scale of a blade part, (c) is explanatory drawing of the blade part seen from the rake face side.

An embodiment of a cutting tool of the present invention will be described with reference to the accompanying drawings.
In addition, the cutting tool of this invention is not limited to the following embodiment, A design change is possible suitably in the range which does not deviate from the main point of this invention.

[Example 1]
The cutting tool of the present invention will be described. In addition, the face mill (front milling) provided with the blade (blade part) used for the cutting of the workpiece | work W as a cutting tool is demonstrated as an example. In the present embodiment, the workpiece W is described as a bevel gear, but it may be a hypoid gear.

  As shown in FIG. 1, a cutting tool 30 constituted by a face mill is provided with a plurality of blade portions 1 </ b> A made of blades at its rotating portion. The blade portion 1A is classified into an outer blade and an inner blade when used as a fail mill cutter. However, since any blade can be applied in the present invention, detailed description thereof is omitted.

  As shown in FIG. 2, the blade portion 1 </ b> A is made of a metal material, and the support portion 2 attached to the rotating portion of the cutting tool 30 and the ridge line portion formed on the upper end of the support portion 2 and formed at the upper end are so-called. It is comprised with the blade edge | tip part 3 used as a top land. In addition, a fixing insertion hole portion 11 through which a fixing jig for fixing to the rotating portion of the cutting tool 30 is inserted is formed in the center of the support portion 2 in a penetrating manner.

  The cutting edge portion 3 is formed with a rake face 5 and a flank face 6 that face in different directions, and the cutting edge 4 is constituted by the intersection of the rake face 5 and the flank face 6. Yes. For example, the effective blade line of the cutting blade 4 can be about 20 mm. Further, a coating layer 10 such as TiAlN is continuously formed on the surfaces of the rake face 5 and the flank face 6 including the cutting edge 4 to ensure high hardness.

  In addition, 1 A of blade parts of the said structure are the structures which can be repeatedly used because the said rake face 5 is repeatedly reground. The detailed process of regrinding will be described in detail later.

  Further, the flank 6 is provided with a plurality of preliminary grooves 9 that are recessed along the blade line direction of the cutting blade 4. More specifically, a large number of the preliminary grooves 9 are arranged in parallel along the regrinding direction in the blade portion 1A. For example, the preliminary grooves 9 have a groove width of about 3 mm and a clearance surface 6 as a reference. The groove depth is 0.2 mm, and these preliminary grooves 9 are arranged at intervals of 0.3 mm. Further, the shape of the groove bottom 9b of the preliminary groove 9 is a round bottom shape convex in the groove depth direction as shown in FIG. 2e. A coating layer 10 is also formed in the preliminary groove 9.

  Further, of the groove edges 9 a and 9 c on both sides of the preliminary groove 9, the groove edge 9 c far from the rake face 5 is formed in the same shape as the cutting edge 4 so that the groove edge Is a preliminary cutting edge X. At the same time, the inner peripheral surface of the preliminary groove 9 connected to the preliminary cutting edge X is a preliminary rake face portion Y parallel to the rake face 5.

  By forming a plurality of the preliminary grooves 9 on the flank 6 of the blade portion 1A, there is a problem in strength reduction at the time of cutting around the cutting blade 4, but the groove edge portion 9a where the preliminary rake surface portion Y is not formed. That is, an inclined surface (tapered surface) in which the inner peripheral surface of the other groove edge portion 9a out of the groove edge portions 9a and 9c facing each other with respect to the groove bottom 9b moves away from the rake face 5 toward the groove bottom 9b. Therefore, sufficient strength is secured against the resistance received during cutting. However, other structures may of course be employed to ensure the strength of the blade portion 1A including the preliminary groove 9.

  The blade portion 1A as described above needs to be reground because the cutting blade 4 gradually wears due to repeated use and the cutting ability decreases. Therefore, first, with respect to the worn cutting edge 4 as shown in FIG. 3 a, the rake face 5 is continued to the preliminary rake face portion Y of the preliminary groove 9 closest to the cutting edge 4 as shown in FIGS. Regrind to position. At this time, if the work is performed while visually recognizing the preliminary groove 9 as a guide of the grinding amount, the grinding work becomes easy and the working efficiency is improved. Then, when the preliminary cutting edge X is exposed to the new rake face 5, the preliminary cutting edge X is used as a new cutting edge 4. Since the new cutting edge 4 is preliminarily formed with the coating layer 10 in the state of the preliminary cutting edge X, the cutting ability similar to that of a new article can be exhibited even if the preliminary cutting edge X is not separately coated. it can.

  In the regrinding, it is desirable to grind so that the angle of the rake face 5 is always maintained. Here, as described above, since the groove bottom 9b of the preliminary groove 9 has a round bottom shape convex in the groove depth direction, in the re-grinding operation as described above, in the groove bottom 9b of the preliminary groove 9 Since the position of the rake face 5 is suitably absorbed by the groove bottom 9b, there is an advantage that accuracy is eased. Moreover, since it becomes difficult to concentrate stress on this groove bottom 9b by setting it as such a shape, it can prevent that a crack etc. arise in this groove bottom 9b.

  Thereafter, when the cutting blade 4 is worn, the blade portion 1A can be reused by sequentially performing the same regrinding process.

  By the way, as shown in FIG. 1, when using a cutting tool 30 having a plurality of blade portions 1 </ b> A, each blade portion 1 </ b> A can be regrinded uniformly according to the position of the preliminary groove 9. There is an advantage that the blade portions 1A at different positions are in a uniform cutting edge state.

[Example 2]
The blade part 1B of the cutting tool 31 comprised with a hob is demonstrated according to FIG. In addition, about the matter which is common in Example 1, the same code | symbol is attached | subjected and description shall be simplified or abbreviate | omitted.

  As shown in FIGS. 4A and 4B, the cutting tool 31 is used for gear cutting, and a large number of blade portions 1B are projected outward from the hob body. The blade portion 1 </ b> B has a rake face 5 formed on the front side in the rotational direction of the cutting tool 31, and a flank face 6 formed so as to be continuous with the rake face 5. And the cutting edge 4 is formed of these intersection lines.

  Further, as shown in FIGS. 4c and 4d, a number of preliminary grooves 9 are formed on the flank 6 of the blade portion 1B along the direction of the blade line of the cutting blade 4. As in the first embodiment, the preliminary groove 9 is formed with a preliminary cutting edge X and a preliminary rake face portion Y.

  When the cutting edge 4 wears and needs to be reground, the preliminary cutting edge X is made a new cutting edge 4 by regrinding the rake face 5 to a position continuous with the preliminary rake face portion Y.

Example 3
The blade part 1C of the cutting tool 32 comprised with a broach is demonstrated according to FIG. In addition, about the matter which is common in Example 1, 2, the same code | symbol is attached | subjected and description shall be simplified or abbreviate | omitted.

  As shown in FIG. 5a, the cutting tool 32 is used for drilling, and a blade portion 1C having a different size and shape is formed in a protruding shape from the broach body. The blade portion 1 </ b> C has a rake face 5 formed on the traveling direction side along the axial direction of the cutting tool 32, and a flank face 6 formed so as to be continuous with the rake face 5. And the cutting edge 4 is formed of these intersection lines.

  Further, as shown in FIGS. 5 b and 5 c, a large number of preliminary grooves 9 are formed in the flank 6 of the blade portion 1 </ b> C along the blade line direction of the cutting blade 4. As in the first and second embodiments, a preliminary cutting edge X and a preliminary rake face portion Y are formed in the preliminary groove 9.

  When the cutting edge 4 wears and needs to be reground, the preliminary cutting edge X is made a new cutting edge 4 by regrinding the rake face 5 to a position continuous with the preliminary rake face portion Y.

  The present invention is not limited only to the configuration described in the above-described embodiment. If the cutting tool can improve the cutting performance of the cutting edge 4 by regrinding the rake face 5, a cutting tool, tap, The present invention can also be applied to a reamer, a pinion cutter, a formed cutter, or an insert tip.

  Moreover, materials suitable for the application such as steel, high speed (high speed steel), cemented carbide, ceramics and the like are applied to the cutting tools 30 to 32.

  Further, the preliminary groove 9 formed on the flank 6 is colored to improve the visibility during re-grinding, and the presence or absence of the coating layer 10 on the cutting edge 4 (including the preliminary cutting edge X). You may make it easy to confirm, or it may become a standard of the remaining number of the reserve grooves 9.

1A to 1C Blade part 4 Cutting edge 5 Rake face 6 Relief face 9 Preliminary groove 9b Groove bottom 10 Coating layer 30 to 32 Cutting tool X Preliminary cutting edge Y Preliminary rake face part

Claims (6)

In a cutting tool that has a blade portion whose cutting edge is the intersection line where the rake face and the flank face intersect, and the rake face of the blade portion is reground, the cutting blade can be used repeatedly.
Preliminary grooves that are recessed along the cutting line direction of the cutting edge are provided on the flank, and further, groove edges at positions far from the rake face among groove edges on both sides of the spare grooves. Is formed into the same shape as the cutting edge, the groove edge is a preliminary cutting edge, and the inner peripheral surface of the preliminary groove coupled to the preliminary cutting edge is a preliminary rake face portion,
A cutting tool, wherein the rake face is reground to a position continuous with the preliminary rake face portion, whereby the preliminary cutting edge becomes a new cutting edge.   The cutting tool according to claim 1, wherein the blade portion is made of a metal material, and the coating layer is continuously formed on the surfaces of the cutting blade and the preliminary cutting blade of the blade portion.   The cutting tool according to claim 1 or 2, wherein a plurality of preliminary grooves are arranged in the regrinding direction of the blade portion.   The inner peripheral surface that faces the inner peripheral surface on which the preliminary rake face portion is formed, with the groove bottom of the preliminary groove as a reference, is configured as an inclined surface that moves away from the rake face toward the groove bottom. The cutting tool according to claim 3.   The cutting tool according to any one of claims 1 to 4, wherein a groove bottom shape of the preliminary groove is a round bottom shape convex in the groove depth direction. For a cutting tool having a cutting edge whose cutting edge is the intersection of the rake face and the flank face, re-grinding the rake face of the cutting edge to re-use the cutting edge In grinding method,
A preliminary groove is formed in the flank along the cutting line direction of the cutting edge, and a groove edge at a position far from the rake face among the groove edges on both sides of the preliminary groove is the cutting edge. The same shape as the blade, the groove edge is used as a preliminary cutting edge, and the inner peripheral surface of the preliminary groove coupled to the preliminary cutting edge is used as a preliminary rake face portion, and the rake face is reground to a position continuous with the preliminary rake face portion. A cutting tool regrind method characterized in that the preliminary cutting edge is used as a new cutting edge.

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