JP5904547B2 - Tip holder - Google Patents

Description

  The present invention relates to a chip holder that is detachably held with respect to a cutting machine that cuts a workpiece by detachably holding a cutting tip that cuts the workpiece.

  2. Description of the Related Art Conventionally, in a cutting machine such as a lathe machine or a milling machine that cuts a metal material, a chip holder is used to hold a cutting chip that cuts a workpiece. The tip holder mainly includes a rod-shaped shank portion that is detachably held by a cutting machine and a head portion that detachably holds a cutting tip. For example, Patent Document 1 below discloses a chip holder in which a cemented carbide shank portion and a steel head portion are joined by brazing.

Japanese Patent Laid-Open No. 08-1425

  However, in the chip holder shown in Patent Document 1, since the cemented carbide shank portion and the steel head portion are joined by brazing, the brazing operation takes time and after brazing. There is a problem in that the mechanical strength of the head portion of the head decreases. That is, in the conventional chip holder, since the shank part and the head part are made of different materials, a slow cooling process is required for a long time in order to prevent cracking and cracking after brazing and this slow cooling. There is a problem that the hardness of the head portion made of steel is lowered by the process, and the mechanical properties are lowered.

  The present invention has been made to cope with the above-described problems, and its purpose is to efficiently perform the joining operation between the shank portion and the head portion, and to reduce the mechanical strength of the head portion after the joining operation. An object of the present invention is to provide a chip holder which is prevented and has excellent mechanical properties.

  In order to achieve the above object, the present invention is characterized by a rod-shaped shank portion that is detachably held by a cutting machine that performs cutting on a workpiece and a cutting tip that cuts the workpiece. A chip holder that is formed by joining the shank portion and the head portion to each other. The shank portion is made of cemented carbide, and the head portion is made of tungsten or tungsten. It is formed of a tungsten alloy as a main component.

In order to achieve the above object, the present invention is characterized by a rod-shaped shank portion that is detachably held by a cutting machine that performs cutting on a workpiece and a cutting tip that cuts the workpiece. In a chip holder configured by joining the shank portion and the head portion to each other, the shank portion is formed of cemented carbide and the head portion is not carbonized tungsten. Or, it is formed of a tungsten alloy whose main component is tungsten that is not carbonized .

  Another feature of the present invention is that, in the chip holder, the shank portion has a convex joint portion in which a part of the joint portion with the head portion protrudes convexly toward the head portion side, In addition, the present invention has a concave joint portion that is recessed in a concave shape corresponding to the convex joint portion at the joint portion with the shank portion.

  According to another feature of the present invention configured as described above, the chip holder is configured to have a convex joint part in which a part of the joint part with the head part in the shank part projects to the head part side. Yes. Thus, the chip holder can increase the contact area of the joint portion between the shank portion and the head portion to improve the joining force, and the cemented carbide shank portion enters the concave joint portion in the head portion. The mechanical strength of the head part can be improved.

  Another feature of the present invention is that in the tip holder, the convex joint portion in the shank portion is formed such that the tip portion extends to a range within 20 mm from the center of gravity of the cutting tip held by the head portion. There is.

  According to another feature of the present invention configured as described above, the tip holder is formed such that the tip of the convex joint portion in the shank portion extends to a range within 20 mm from the center of gravity of the cutting tip held by the head portion. ing. Thereby, the chip holder can arrange the cemented carbide shank portion in the vicinity of the cutting tip for cutting, and can effectively suppress the occurrence of chatter vibration during the cutting.

Another feature of the present invention is that in the chip holder, the convex joint portion in the shank portion is formed in a shape that tapers toward the tip portion, and the head portion is formed by the convex joint portion in the shank portion. There exists in providing the cutting waste discharge path extended along the axial direction of a shank part on both sides.

According to another feature of the present invention configured as described above, the tip holder is formed in a shape in which the convex joint portion in the shank portion tapers toward the tip portion, and the convex shape of the shank portion in the head portion. Cutting waste discharge paths extending along the axial direction of the shank portion are formed on both sides of the joint portion. As a result, the chip holder can effectively discharge the cutting waste during the cutting of the workpiece, can improve the cutting performance, and prevent damage to the peripheral portion of the cutting tip in the chip holder due to the cutting waste. be able to.

Further, in the tip holder, the convex joint portion in the shank portion may be formed in parallel to a main component force of the cutting resistance acting on the cutting tip at the time of cutting the workpiece. According to this, in the tip holder, the convex joint portion in the shank portion is formed in parallel with the main component force of the cutting resistance acting on the cutting tip during the cutting process on the workpiece. In other words, a cutting resistance in which a main component force, a feed component force, and a back component force are combined is applied to the chip holder for cutting the workpiece. In this case, the main component force constituting the cutting force is a force far greater than the feed component force and the back component force. Therefore, the tip holder can improve the rigidity by forming the convex joint portion in the shank portion made of cemented carbide so as to extend in parallel to the main component force.

In the chip holder, the cutting process performed on the workpiece may be a boring process. According to this, the chip holder is used for boring a workpiece. In this case, boring on the work piece is to make a hole in the work piece, and the shank portion in the tip holder becomes longer according to the depth of the hole. Easy to be affected. Therefore, according to the chip holder according to the present invention, chatter vibration during cutting of the workpiece can be effectively suppressed, which is suitable for boring.

The present invention can be implemented not only as an invention of a chip holder but also as an invention of a manufacturing method of a chip holder.

Specifically, a rod-shaped shank portion that is detachably held by a cutting machine that performs cutting on a workpiece, and a head portion that detachably holds a cutting tip that cuts the workpiece. In the manufacturing method of the chip holder constituted by joining the shank part and the head part to each other, a convex joint part protruding in a convex shape is formed at the end of the first round bar made of cemented carbide. And a step of forming a concave joint that is recessed in a concave shape corresponding to the convex joint in a second round bar made of tungsten that is not carbonized or tungsten alloy that is mainly composed of tungsten that is not carbonized. A joining step in which the convex joint and the concave joint are fitted to join the first round bar and the second round bar together, and the second round bar joined to the first round bar Chip support for detachably supporting the cutting tip with respect to It may include a step of forming a head portion having road respectively. In this case, in the manufacturing method of the chip holder, the second round bar in the step of forming the concave joint portion may be formed to have an outer diameter larger than the final outer diameter of the head portion.

It is a top view which shows roughly the whole structure of the chip holder which concerns on one Embodiment of this invention. It is a front view which shows roughly the whole structure of the chip holder shown in FIG. It is a partially broken top view which shows typically the cutting process state of the chip holder shown in FIG. FIG. 3 is a partially broken front view schematically showing a cutting state of the chip holder shown in FIG. 2. (A)-(D) are explanatory drawings which show typically the manufacture process of the chip holder shown in FIG.

  Hereinafter, an embodiment of a chip holder according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing an outline of the overall configuration of a chip holder 100 according to the present invention. FIG. 2 is a front view showing an outline of the entire configuration of the chip holder 100 shown in FIG. Note that each drawing referred to in the present specification is schematically represented by exaggerating some of the components in order to facilitate understanding of the present invention. For this reason, the dimension, ratio, etc. between each component may differ. The tip holder 100 holds a cutting tip 120 for cutting a workpiece and is attached to a cutting machine such as a lathe or a milling machine (not shown).

(Configuration of chip holder 100)
The chip holder 100 includes a shank portion 101. The shank portion 101 is a portion that is detachably held by a holder chuck in a cutting machine (not shown), and is configured by forming a cemented carbide in a rod shape. More specifically, the shank portion 101 is formed of a substantially round bar, and two flat portions 102 extending in parallel with each other along the axial direction are formed on the outer surface of the round bar. Configured. These two flat portions 102 are flat portions for stably holding the chip holder 100 on a holder chuck in a cutting machine.

  A convex joint 103 is formed at one end (left side in the figure) of the shank 101. The convex joint portion 103 is a portion for joining the shank portion 101 to a head portion 110 described later, and has a substantially V shape that protrudes toward the center of the shank portion 101 in a plan view and has a tapered tip portion. It is formed in a letter shape. In the present embodiment, the tip end of the convex joint 103 is sharply formed at an angle of about 60 °. The head part 110 is joined to the convex joint part 103.

  The head part 110 is a part that detachably holds a cutting tip 120 that cuts a workpiece, and is made of a tungsten alloy. More specifically, the head part 110 mainly includes a chip support part 111 formed in a plate shape and a concave joint part 115 joined to the convex joint part 103 of the shank part 101. Of these, the tip support portion 111 is a portion that detachably holds the cutting tip 120, and is configured by forming a tip pocket 112 at the tip of a plate-like body having a flat portion.

  The tip pocket 112 is a portion into which the cutting tip 120 is detachably fitted, and is formed in a concave shape with a shape that can fit the cutting tip 120 without play, that is, a shape corresponding to the shape of the cutting tip 120. . In this case, the tip pocket 112 is formed in a shape in which a blade used for cutting in the cutting tip 120 protrudes from the end portion of the tip support portion 111 and is formed to a depth substantially the same as the thickness of the cutting tip 120. ing. In the present embodiment, the chip pocket 112 is formed in a substantially triangular shape in plan view corresponding to the shape of the cutting chip 120. In addition, the tip pocket 112 is formed with an escape portion 113 for avoiding interference with the protruding corner portion of the cutting tip 120 on the back side portion, and the cutting tip 120 on the bottom portion on which the cutting tip 120 is placed. A female screw 114 is formed for fixing the screw with a screw.

  The concave joint portion 115 is a portion for joining the head portion 110 to the convex joint portion 103 of the shank portion 101, and has a substantially V-shape with a concave inner width narrowing toward the center portion of the head portion 110 in plan view. Is formed. In the present embodiment, the deepest portion of the concave joint 115 is sharply formed at an angle of about 60 °, like the convex joint 103. In this case, the deepest portion of the concave joint 115 is formed as close as possible to the center of gravity of the cutting tip 120 held in the tip pocket 112. In the present embodiment, the deepest portion of the concave joint 115 is formed at a position of about 12 mm at a linear distance from the center of gravity of the cutting tip 120 held in the tip pocket 112.

The recessed joint 115, as shown in FIGS. 3 and 4, in the case of cutting a workpiece WK using a chip holder 100, the main component force F _M of the cutting resistance acting on the cutting tip 120 On the other hand, the convex joint 103 of the shank 101 is formed in a parallel direction. In this case, the main component force F _M acting on the cutting tip 120, at the point of contact with the cutting tip 120 and the workpiece WK in cutting the workpiece WK the cutting tip 120 are relatively rotated (cutting portion) a force acting in a tangential direction relative to the rotational direction, constituting the cutting resistance with the back component force F _B acting on the cutting depth direction line of the feeding component force F _F and the cutting tip 120 acting on the feeding direction line of the cutting tip 120 It is one of the component forces to be generated, and the maximum component force among these component forces.

  In a portion between the chip support portion 111 and the concave joint portion 115 in the head portion 110, cutting waste discharge paths 116 are formed along both sides of the concave joint portion 115, respectively. Each cutting waste discharge path 116 is a passage for positively removing the cutting waste generated by cutting the workpiece WK by the cutting tip 120 from the top of the head part 110, and is formed from the chip pocket 112 to the concave joint 115. Cut along a curved surface along both sides.

  The cutting tip 120 is a tip-shaped tool having a cutting edge for cutting the workpiece WK. In the present embodiment, the cutting tip 120 is formed in a substantially equilateral triangle in plan view, and has a cutting edge formed at each vertex. That is, in the present embodiment, the cutting tip 120 is configured by a so-called throw-away tip. In FIGS. 1 and 2, the cutting tip 120 is indicated by a two-dot chain line.

(Manufacture of chip holder 100)
Next, a manufacturing method of the chip holder 100 configured as described above will be described. First, as shown in FIG. 5A, the operator uses a cemented carbide round bar MT ₁ having the same or substantially the same outer diameter as the shank portion 101 and the outer diameter of the head portion 110. We are prepared respectively and round rod MT ₂ of tungsten having a larger outer diameter.

Next, the worker, as shown in FIG. 5 (B), each shaped convex joint portions 103 and the concave joining part 115 at the end of each one of the round bar MT ₁ and round bar MT _2. In this case, the operator, respectively forming convex joint portions 103 and the concave joining part 115 by grinding the respective one end portions of the round bar MT ₁ and round bar MT ₂ using a grinding apparatus (not shown) To do.

Next, the worker, as shown in FIG. 5 (C), joining the round bar MT ₁ and round bar MT ₂ together. Specifically, the operator, after each other fitted and concave joint portion 115 formed in a convex shape junction 103 and round bar MT ₂ formed in the round bar MT ₁ together, silver brazing the mating portion Join by attaching. In this case, the worker, but a round bar MT ₁ and round bar MT ₂ which is integrally brazed may perform slow cooling gradually cool over time, air cooling, oil cooling or water cooling It can also be cooled rapidly. This is a round rod MT ₂ are both of the same type material as a round rod MT ₁ and the head portion 110 of the shank portion 101, that is, because it is composed of tungsten as a main component, distortion in the brazing process, This is because the occurrence of gaps and cracks can be suppressed.

Next, the operator, as shown in FIG. 5 (D), the outer shape of a round rod with forming each tip support portion 111 and the chip discharge passage 116 includes a chip pocket 112 relative round bar MT ₂ Then, the head part 110 is formed. Specifically, the operator, to mold the head portion 110 by performing milling and lathing relative round bar MT _2. In this case, the operator, so that the ridge line of the convex joint portions 103 and the concave joining part 115 fitted each other parallel to the main component force F _M acting on the cutting tip 120 which is supported by the tip support 112 chips The support part 112 is molded. Thus, it is possible to form the chip holder 100 convex joint portions 103 while being formed parallel to the main component force F _M acting on the cutting tip 120.

Next, the operator performs finishing. Specifically, the operator, finish the shank portion 101 and head portion 110 to form a planar portion 102 with adjust each the outer shape of a round rod MT ₁ and the head portion 110 by grinding, respectively. Further, the operator performs various post-treatments for improving the durability such as the design and the wear resistance of the external appearance of the chip holder 100 by blasting or coating the shank part 101 and the head part 110 as necessary. It can be performed.

(Operation of chip holder 100)
Next, the operation of the chip holder 100 configured as described above will be described. First, the operator prepares the tip holder 100 and the cutting tip 120, respectively. Next, the operator fits the cutting tip 120 into the tip pocket 112 of the head portion 110 in the tip holder 100 and fixes it with a screw. Next, the operator holds the chip holder 100 holding the cutting chip 120 on a holder chuck in a cutting machine (not shown). Thereby, the operator can perform the cutting of the workpiece WK using the cutting tip 120 held by the tip holder 100.

Specifically, the operator sets the workpiece WK on the cutting machine, and then operates the operation panel of the cutting machine to move the two relative to each other while bringing the cutting tip 120 into contact with the workpiece WK. By doing so, the workpiece WK is cut. When the workpiece WK is cut by the cutting machine, the chip holder 100 continues to hold the cutting tip 130 that cuts the workpiece WK. In this case, in the chip holder 100, since the shank portion 101 is made of a cemented carbide and the cemented carbide is disposed up to the tip pocket 112 in the head portion 110, the workpiece WK is cut. It is possible to perform cutting with high accuracy while suppressing the occurrence of chatter vibrations. In this case, the convex joint portions 103 of the shank portion 101 is formed extending in parallel to the main component force F _M acting on the cutting tip 120 of the distal end portion is supported by the tip support 111. Thus, the chip holder 100 can be supported accurately with high rigidity cutting tip 120 which acts primary component force F _M by cutting of the workpiece WK.

  Moreover, since the chip holder 100 has the cutting waste discharge path 116 formed in the part between the chip support part 111 and the concave joint part 115 in the head part 110, the cutting waste generated by cutting the workpiece WK is removed. It can be quickly removed from the head part 110. In this case, in particular, when cutting the inner surface of the hole with respect to the workpiece WK, that is, when performing boring, it is difficult to discharge the cutting waste from the hole, so the cutting waste discharge path 116 is formed. Therefore, the accuracy of the boring process can be improved. In this case, since the head part 110 is made of a tungsten alloy, the chip holder 100 can suppress damage such as wear or breakage due to contact or collision of cutting waste. In this case, according to the inventor's demonstration experiment, in the chip holder 100 according to the present invention, it is confirmed that the wear resistance maintenance time is about 5 to 10 times that in the case where the head part 110 is made of a conventional steel material. did.

  On the other hand, when finishing the cutting of the workpiece WK, the operator removes the chip holder 100 from the holder chuck after stopping the operation of the cutting machine. Next, when the cutting edge of the cutting tip 130 and its peripheral wear are significant, the operator can change the direction to another cutting edge in the cutting tip 130 or replace the cutting tip 130 itself with a new cutting tip 130. .

  As can be understood from the above description of operation, according to the above embodiment, the chip holder 100 includes the shank portion 101 held by the cutting machine made of cemented carbide and the head portion 110 made of tungsten alloy. ing. In other words, in the chip holder 100, the shank portion 101 and the head portion 110 are made of the same kind of material and joined together. For this reason, in the chip holder 100 according to the present invention, when the shank portion 101 and the head portion 110 are brazed, it is not always necessary to perform slow cooling after the joining step. Thereby, the chip holder 100 can improve the precision and efficiency in the joining process of the shank part 101 and the head part 110, and can prevent the strength reduction of the head part 110 after the joining process. Further, in the chip holder 100 according to the present invention, since the shank portion 101 and the head portion 110 are made of the same material, the shank portion 101 and the head portion 110 can be joined by brazing. Compared with the case where brazing is performed between different materials, it is possible to adjust the component of the brazing very easily. Further, the chip holder 100 is formed by suppressing the occurrence of chatter vibration during cutting of the workpiece WK because the head portion 110 is made of a tungsten alloy whose mechanical strength is higher than that of a general steel material. The accuracy can be improved and the durability can be improved by suppressing damage and deterioration due to cutting.

  Furthermore, in carrying out the present invention, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the object of the present invention.

  For example, in the above embodiment, the chip holder 100 has the head portion 110 made of a tungsten alloy. However, the head part 110 in the chip holder 100 is not necessarily limited to the above embodiment as long as it is made of a material mainly composed of tungsten. In this case, the material having tungsten as a main component means that the proportion of tungsten in the constituent components included in the material constituting the head unit 110 is the highest. Therefore, the head part 110 in the chip holder 100 may be made of a tungsten alloy, but it may mean that it may be made of only tungsten.

  Moreover, in the said embodiment, the chip holder 100 comprised the convex junction part 103 and the concave junction part 115 which are the junction parts of the shank part 101 and the head part 110 in the substantially V shape. However, the convex joint 103 and the concave joint 115 may have any shape that can join the shank part 101 and the head part 110. In this case, the convex joint 103 and the concave joint 115 can be secured in a U-shape or W-shape in addition to the V-shape, so that a wide joint area can be secured. It can be firmly joined.

Further, the orientation of the tip portion of the convex joint portions 103, in other words, the orientation of the ridge line of the convex joint part 103, parallel to the main component force F _M acting on the cutting tip 120 which is supported by the tip support 111 Is formed. Thus, the chip holder 100 can be supported accurately with high rigidity cutting tip 120 which acts primary component force F _M by cutting of the workpiece WK. In this case, the orientation of the tip portion of the convex joint portions 103, since it is sufficient to extend along the main component of force F _M acting on the cutting tip 120, be somewhat inclined relative to the main component force F _M It ’s good. According to trials of the inventors, the orientation of the tip portion of the convex joint portions 103 have found that to be formed at an angle of up to about 45 ° with respect to the main component force F _M is suitable.

  Note that the shank portion 101 and the head portion 110 do not necessarily have to be joined by the convex joint portion 103 and the concave joint portion 115, and the tip portions of the shank portion 101 and the head portion 110 are formed in a simple flat shape. It can also be joined by brazing. That is, in the shank part 101 and the head part 110, the convex joint part 103 and the concave joint part 115 can be omitted.

  Further, the shank part 101 and the head part 110 do not necessarily have to be joined by brazing, but a joining method other than brazing, for example, TIG welding, MIG welding, electron beam welding, laser beam welding, resistance welding, friction Bonding can be performed by various bonding methods such as a pressure welding method or a diffusion bonding method.

  In the above embodiment, the tip of the convex joint 103 is disposed at a position of about 12 mm from the center of gravity of the cutting tip 120 supported by the tip support 111. Thereby, the cutting tip 120 chatter vibration supported by the tip support part 111 at the time of cutting of the workpiece WK can be effectively suppressed. However, the tip end of the convex joint 103 is not necessarily limited to the above embodiment, and may be arranged at a position 12 mm or more away from the center of gravity of the cutting tip 120. However, according to the inventor's demonstration experiment, the tip of the convex joint 103 is effectively chattered by being disposed within a range of about 20 mm from the center of gravity of the cutting tip 120 supported by the tip support 111. It was confirmed that vibration can be suppressed.

  Moreover, in the said embodiment, since the chip | tip waste discharge path 116 is formed in the part between the chip | tip support part 111 and the concave junction part 115 in the head part 110, the chip | tip holder 100 cuts the workpiece WK. Can be quickly removed from the head portion 110. However, the chip holder 100 is not necessarily provided with the cutting waste discharge path 116. For example, when the chip holder 100 is used for cutting the outer shape of the workpiece WK or when cutting is performed while supplying cutting oil to the cutting portion, the cutting waste is ensured. The discharge path 116 can be omitted. On the other hand, in the case where the chip holder 100 is machined at a portion where the cutting waste dischargeability is low, such as the inner shape (for example, boring) of the workpiece WK, the cutting waste discharge path 116 is formed to form the cutting waste. It is possible to remarkably improve the discharge performance.

WK ... workpiece, MT 1 _... round bar, MT 2 _... round bar, F M _... main component force, F F _... feeding component force, F B _... back component force,
DESCRIPTION OF SYMBOLS 100 ... Chip holder, 101 ... Shank part, 102 ... Plane part, 103 ... Convex joint part,
DESCRIPTION OF SYMBOLS 110 ... Head part, 111 ... Chip support part, 112 ... Chip pocket, 113 ... Escape part, 114 ... Female screw, 115 ... Concave joint part, 116 ... Cutting waste discharge path.

Claims (6)

A rod-shaped shank that is detachably held by a cutting machine that performs cutting on a workpiece;
A head part that detachably holds a cutting tip for cutting the workpiece,
In the chip holder configured by joining the shank part and the head part to each other,
The shank portion is made of a cemented carbide,
2. The chip holder according to claim 1, wherein the head portion is formed of tungsten that is not carbonized or a tungsten alloy that contains tungsten that is not carbonized as a main component. In the chip holder according to claim 1,
The shank portion is
A part of the joint part with the head part has a convex joint part projecting convexly toward the head part side;
The head portion is
A chip holder having a concave joint portion recessed in a concave shape corresponding to the convex joint portion at a joint portion with the shank portion. In the chip holder according to claim 2,
The convex joint in the shank is
A tip holder, wherein a tip portion is formed to extend to a range within 20 mm from the center of gravity of the cutting tip held by the head portion. In the chip holder as described in any one of Claim 2 or Claim 3,
The convex joint in the shank is
It is formed in a shape that tapers toward the tip,
The head portion is
Tip holder according to claim Rukoto with a chip discharge passage extending along the axial direction of the shank portion on each side of the convex joint portions in the shank portion. A rod-shaped shank that is detachably held by a cutting machine that performs cutting on a workpiece;
A head part that detachably holds a cutting tip for cutting the workpiece,
In the manufacturing method of the chip holder configured by joining the shank part and the head part to each other,
Forming a convex joint projecting in a convex shape at the end of the first round bar made of cemented carbide;
A step of forming a concave joint recessed in a concave shape corresponding to the convex joint in a second round bar made of tungsten that is not carbonized or tungsten alloy mainly composed of tungsten that is not carbonized;
A joining step of fitting the convex joint and the concave joint to join the first round bar and the second round bar together;
Forming a chip support portion for detachably supporting a cutting tip with respect to the second round rod body joined to the first round rod body and a head portion having a cutting waste discharge path. A manufacturing method of a chip holder, which is characterized. In the manufacturing method of the chip holder according to claim 5,
The method of manufacturing a chip holder, wherein the second round bar in the step of forming the concave joint is formed to have an outer diameter larger than a final outer diameter of the head portion.

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