JP2005186200A - Throw-away tip and cutting tool using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting tool, capable of holding down the manufacturing cost and having high degree of freedom for designing the tip. <P>SOLUTION: This throw-away tip is formed substantially rod-like, and the rear end part of an insert member 7 having a cutting blade 6 projected sideways from the peripheral surface of the rod-like part at the forward end in the longitudinal direction and made of a hard alloy is inserted in an insert hole 9 provided in a shank member 8, which is made of steel or an alloy, and the side and the rear end of which are constrained on a tool holder 2 to fix the insert member. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a throw-away tip in which a tip has a substantially rod shape and a cutting edge projects laterally from a circumferential surface of the rod-like portion.

  Conventionally, as a cutting tool used for grooving or threading, a generally rod-shaped (bar-shaped) throw-away tip 21 having a cutting edge at one or both ends is inserted into the hole 24 of the holder 23 as shown in FIG. In addition, there are known ones that are fixed with bolts 25 or the like.

Japanese Patent Laid-Open No. 2001-71204 discloses a method for fixing a bar-shaped throw-away tip having cutting edges at both ends, in which a stored cutting blade is brought into contact with a bolt fitted from the rear end side of a holder. The method of fixing is described.
JP 2001-71204 A

  However, in the conventional bar-shaped throw-away tip shown in FIG. 6, since the entire bar is made of a hard alloy such as a cemented carbide, the manufacturing cost increases and it is difficult to process into a complicated shape. There was a limit to the shape design.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a cutting tool that can keep the manufacturing cost low and that has a high degree of freedom in the design of the chip shape. .

  By adopting the following configuration, the present inventors can reduce chip manufacturing costs and increase the degree of freedom in chip design, and supply processing and cutting oil to increase the binding force of the chip. It has been invented that the process of providing the holes is easy and inexpensive.

  That is, the throw-away tip of the present invention has a substantially rod-like shape, and the rear end portion of the insertion member made of a cemented carbide having a cutting edge protruding laterally from the peripheral surface of the rod-like portion at the longitudinal tip, The rear end face is inserted into an insertion hole provided in a shank member made of steel or alloy constrained by the tool holder, and is adhered thereto.

  Here, the rear end surface of the shank member is formed so that the length from the front end is partially different with respect to the longitudinal direction, so that the restraining force and the attachment position accuracy of the throw-away tip can be increased.

  In addition, according to the present invention, it is possible to easily form a restrained portion processed to restrain the throw-away tip on the side surface of the shank member, and to increase the restraining force and attachment position accuracy of the throw-away tip. Can do.

  Furthermore, according to the present invention, it is possible to easily form an oil hole through which the cutting oil supplied from the tool holder is passed in the shank member, thereby making it easy to perform cutting.

  Further, by inserting and fixing the two insertion members into the insertion holes provided at both ends of the shank member, one cutting tip can have two cutting edges, and the cutting process can be performed. Can be doubled.

  In addition, the insertion member can be press-fitted and fixed in the insertion hole of the shank member, and the surface of the insertion member can be easily manufactured by a physical vapor deposition method such as an ion plating method. It is desirable in that the covering film can be easily formed.

  Furthermore, the cutting tool of the present invention is a cutting tool in which the side surface and the rear end surface of the above throwaway tip are constrained by the tool holder, and can be suitably used especially for inner diameter processing, especially for minimum inner diameter processing.

  The cutting tool of the present invention has a substantially rod shape, and has a rear end portion of a cemented carbide member having a cutting edge projecting laterally from the circumferential surface of the rod-shaped portion at a longitudinal tip, a side surface and a rear portion. Because the end face is inserted into an insertion hole provided in a shank member made of steel or alloy constrained by the tool holder and bonded, the chip manufacturing cost can be reduced and the degree of freedom in chip design Therefore, it is possible to easily and inexpensively perform processing for increasing the binding force of the chip, processing for providing a hole for supplying cutting oil, and the like.

  FIG. 1 which is a plan view of a cutting tool for inner diameter machining, which is an example in which the embodiment of the throw-away tip of the present invention is mounted in a holder, and the throw-away tip mounted on the cutting tool of FIG. Description will be made with reference to FIG. 2 which is a) a plan view and (b) a side view.

  According to FIG. 1, a cutting tool (hereinafter simply referred to as a tool) 1 has a hole 3 formed at the tip of a tool holder 2, and a throw-away tip (hereinafter simply referred to as a tip) 4 in the hole 3. It is attached.

  As shown in FIG. 2, the tip 4 of the present invention has a substantially rod shape, and includes an insert member 7 made of cemented carbide having a cutting edge 6 projecting laterally from the circumferential surface of the rod-shaped portion at the longitudinal end. The rear end portion is inserted and fixed in an insertion hole 9 provided in a shank member 8 made of steel or alloy whose side surface and rear end surface 10 are restrained by the holder 2. .

  According to such a configuration, the cutting edge portion that requires wear resistance and fracture resistance is formed of a hard alloy, and the shank member 8 is formed of steel or an alloy that is inexpensive and easy to process. Therefore, the manufacturing cost of the chip 4 can be reduced and the design freedom of the chip 4 can be increased, and the process for increasing the binding force of the chip 4 and the process of providing a hole for supplying cutting oil are easy. And it can be made inexpensive.

  Note that the cross-sectional shape of the insertion member 7 and the corresponding insertion hole 9 is circular in terms of strength and ease of processing. In order to improve the discharge performance and prevent interference with the work material wall surface after processing, it may be an elliptical shape, a shape obtained by cutting out a part of a circle or an ellipse, or a polygonal shape. Good. In addition, the shape of the insertion member 7 is connected by a plurality of arcs such that the cross-sectional shape of the portion forming the cutting blade 6 is inside the circle including the cutting blade 6 as shown in FIG. It is desirable to have a shape.

  Here, according to FIGS. 1 and 2, the rear end surface 10 of the shank member 8 is inclined obliquely so that the length from the front end is partially different from the longitudinal direction. By abutting and fixing to the cylindrical locking member 12 attached to the holder 2, the cutting blade 6 can be positioned and mounted with high precision even when the chip 4 is replaced, and the chip 4 is firmly fixed. Therefore, it is possible to prevent the tip 4 from rotating and the position of the cutting edge 6 from being displaced or the tip 4 from being loosened during cutting. Further, according to FIG. 1, the shank member 8 is restrained and fixed by the screw member 13 provided in the holder 2.

  According to FIG. 1, as described above, the rear end surface 10 of the chip 4 is inclined obliquely with respect to the longitudinal direction of the rod-shaped body, and there is a merit that dimensional accuracy is high in manufacturing and manufacturing is easy. The inclination angle θ of the rear end surface 10 (the angle of the cut surface with respect to the virtual end surface perpendicular to the longitudinal direction of the rod-shaped body) is 30 to 60 °, and particularly 40 to 50 °, so that the chip restraining force is improved and the rear end surface 10 It is desirable in terms of prevention of chipping and ease of manufacturing.

  In the configuration of FIG. 1, the cutting edge 6 of the chip 4 is processed by using the same jig as that of the holder 2 provided with the locking member 12 in the cutting edge processing step of manufacturing the chip 4. Chips with high dimensional accuracy can be processed.

  Further, according to FIG. 2, the shank member 8 is made of an alloy such as steel or stainless steel, so that the processing is easy, and the notch-shaped restraining portion 14 that is worked to restrain the chip 4 on the side surface of the shank member 8. The screw member 15 for fixing the holder 2 to the restraining portion 14 can be inserted to increase the restraining force and mounting position accuracy of the chip 4. In addition, according to this invention, the shape of this restraint part 14 is not limited to the notch shape of FIG. 2, The shape cut out planarly may be sufficient. Further, a cam, a spring or the like can be used instead of the screw member 15.

  Furthermore, according to FIG. 1, since the processing of the shank member 8 is easy, the oil hole 16 for passing the cutting oil supplied from the holder 2 into the shank member 8 can be easily formed. With this oil hole 16, cutting oil can be supplied from a place closer to the cutting edge, and the cutting oil can be applied to the cutting edge efficiently and reliably, cutting can be performed easily, and the tool life is extended. Can be improved, and the surface roughness of the work material can be made smooth.

  The insertion member 7 may be provided with an oil hole communicating with the oil hole 16 of the shank member 8, but in FIG. 2, the oil hole 16 is provided only in the shank member 8 in order to maintain the strength of the insertion member 7. The cutting oil flowing out from the tip of the shank member 8 is configured to moisten the cutting blade 6 through the wall surface and cutting surface of the work material and the side surface of the insertion member 7 of the chip 4.

  Moreover, the insertion member 7 and the shank member 8 can be fixed by press-fitting, and can be easily formed when a hard coating film is formed on the surface of the insertion member by a physical vapor deposition method such as an ion plating method. desirable. That is, as a method for fixing the insertion member 7 and the shank member 8, a method using an adhesive can also be adopted. However, when the hard coating film is formed after the insertion member 7 and the shank member 8 are bonded, an adhesive is used. It is necessary to control the temperature rise during film formation so that the agent does not deteriorate, and it is difficult to secure the conductivity of the insertion member 7 and film formation may be difficult.

  Further, as shown in FIG. 4, it is desirable that the tip 4 has a shape such that the tip of the cutting blade 6 including the tip of the cutting blade 6 has a circular cross section of the insertion member 7 (rod-like portion) in terms of easy manufacturing. Further, the side surface following the cutting edge 6 of the insertion member 7 is processed into a taper shape or (b) curved surface in FIG. 4 in terms of prevention of interference with the work material and chip dischargeability. In particular, (b) a curved surface is desirable in terms of preventing interference with the work material and improving the strength of the rod-shaped portion of the insertion member 7.

  Furthermore, according to FIG. 5, the two insertion members 7 and 7 ′ are inserted into the insertion holes 9 and 9 ′ provided at both ends of the shank member 8, and bonded, One chip 18 has two cutting edges, and the cutting process can be doubled.

  On the other hand, the locking member 12 may be steel, but may be made of cemented carbide, cermet, or ceramics in terms of wear resistance and plastic deformation resistance. In addition, it is desirable that the locking member 12 is formed in a cylindrical shape that allows the portion that abuts the chip 4 to be accurately aligned and can be easily processed, but the side surface is partly cut away in the longitudinal direction and abuts the chip 4. The portion may be a flat shape or a polygonal prism shape.

  On the other hand, the insert and tool of the present invention can be used for turning, but is particularly suitable for machining an inner diameter of a minimum diameter of 4 mm or less, particularly 3 mm or less, and stable and high in such a minimum inner diameter machining. It is possible to achieve high quality processing with a smooth finish surface with accuracy.

It is a top view which shows one Embodiment of the cutting tool which mounted | wore the throw away tip of this invention with the holder. It is (a) top view about the throw away tip with which the cutting tool of FIG. 1 is mounted | worn, (b) It is a side view. It is a top view which shows other embodiment of the cutting tool which mounted | wore the throw away tip of FIG. 2 with the holder. It is the figure which looked at the throw away tip of FIG. 2 from the front-end | tip. It is a schematic sectional drawing which shows other embodiment of the throw away tip of this invention. It is a schematic sectional drawing which shows an example of the conventional throw away tip.

Explanation of symbols

1 Cutting tool
2 Holder 3 Hole 4, 18 Throw away tip (chip)
6 Cutting blade 7 Inserting member 8 Shank member 9 Inserting hole 10 Rear end surface 12 Locking member 13, 15 Screw member 14 Restraining portion 16 Oil hole

Claims (7)

Steel having a substantially rod-like shape, the rear end portion of the insertion member made of a hard alloy having a cutting edge protruding laterally from the circumferential surface of the rod-like portion at the front end in the longitudinal direction, the side surface and the rear end surface being restrained by the tool holder Alternatively, the throw-away tip is formed by being inserted into an insertion hole provided in a shank member made of an alloy and fixed. The throw-away tip according to claim 1, wherein the rear end surface of the shank member is formed so that the length from the front end is partially different with respect to the longitudinal direction. The throw-away tip according to claim 1 or 2, wherein a constraining portion processed to constrain the throw-away tip is formed on a side surface of the shank member. The throw-away tip according to any one of claims 1 to 3, wherein an oil hole for passing a cutting oil supplied from the tool holder is formed in the shank member. The throw-away tip according to any one of claims 1 to 4, wherein the two insertion members are inserted into and inserted into insertion holes provided at both ends of the shank member. The throw-away tip according to any one of claims 1 to 5, wherein the insertion member is press-fitted and fixed in an insertion hole of the shank member. A cutting tool formed by restraining the side surface and the rear end surface of the throw-away tip according to any one of claims 1 to 6 with the tool holder.

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