JP2005186201A - Throw-away tip and cutting tool using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a throw-away tip and a cutting tool, heightening the fitting positioning accuracy of a cutting blade and firmly binding the cutting blade. <P>SOLUTION: This throw-away tip 4 is substantially rod-like and provided with the cutting blade 6 projected sideways from the peripheral surface of the rod-like part at the forward end in the longitudinal direction. The rear end face 10 of the tip 4 is an inclined surface partially different in length from the forward end in the longitudinal direction, and the side surface of the tip 4 is provided with a binding part 14 for binding the tip 4. <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 protrudes in a lateral direction from a peripheral 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. 5, since the protruding length of the bar is variable, there is a problem that the protruding length tends to vary when the tip 21 is replaced, and the position of the cutting blade is displaced. In addition, since the side surface of the bar is pressed and fixed with the bolt 25, the binding force in the rotation direction of the tip 21 is particularly weak, the tip 21 rotates during cutting, the position of the cutting edge is displaced, or the tip 21 is loosened. There was a problem that it was easy.

  Further, in the cutting tool described in Japanese Patent Laid-Open No. 2001-71204, there is a risk that the cutting blade abutted on the bolt may be lost due to vibration during mounting or during cutting, and the opposite cutting blade is used. In this case, there is a problem that the position accuracy of the cutting edge is shifted because the degree of chipping or wear of the cutting edge is different each time.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a throw-away tip that can be firmly restrained and a cutting tool using the throw-away tip while improving the accuracy of the mounting position of the cutting blade. It is in.

  By adopting the following configuration, the present inventors can improve the mounting position accuracy of the cutting blade even when the chip is replaced, and in particular, can improve the restraining force with respect to the rotation direction of the chip, thereby achieving stable machining. Invented that it would be possible.

  That is, the throw-away tip of the present invention has a substantially rod shape, and the throw-away tip having a cutting edge protruding laterally from the peripheral surface of the rod-like portion at the longitudinal tip, the rear end surface of the throw-away tip is a longitudinal portion. The length from the tip is partially different with respect to the direction, and a restraining portion for restraining the throwaway tip is provided on a side surface of the throwaway tip. Is.

  Here, at least the cutting blade is formed by an insertion member made of a hard alloy, and the rear end portion of the insertion member is placed in a shank member made of steel or alloy whose side surface and rear end surface are restrained by the tool holder. Inserting and fixing in the provided insertion hole can reduce the chip manufacturing cost and increase the degree of freedom in chip design, and supply processing and cutting oil to increase the chip's binding force. This is desirable in that the processing for providing the holes for the purpose is easy and inexpensive. Further, in this case, the insertion member can be press-fitted and fixed in the insertion hole of the shank member, and can be easily manufactured, and physical vapor deposition such as an ion plating method can be easily performed on the surface of the insertion member. It is desirable in that a hard coating film can be easily formed by this method.

  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.

  Furthermore, by inserting the two insertion members into insertion holes provided at both ends of the shank member and fixing them, it is possible to have two cutting blades with one chip. The cutting process can be doubled with this tip.

  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 is a throwaway tip having a substantially rod shape and having a cutting edge protruding laterally from the circumferential surface of the rod-like portion at the longitudinal tip, and the rear end surface of the throwaway tip is in the longitudinal direction On the other hand, it is formed so as to have a portion having a short length from the tip, and a restraining portion for restraining the throwaway tip is provided on a side surface of the throwaway tip. With this, the accuracy of the cutting blade mounting position can be increased even when the chip is replaced, and in particular, the restraining force in the rotation direction of the chip can be improved, and stable machining is possible.

  FIG. 1 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. FIG. 2) is a plan view, and FIG. 2 is 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.

  The tip 4 of FIGS. 1 and 2 has a substantially rod shape, and has a rear end portion of an insert member 7 made of a cemented carbide having a cutting edge 6 projecting laterally from the circumferential surface of the rod-like portion at the longitudinal end. The side face and the rear end face 10 are inserted into an insertion hole 9 provided in a shank member 8 made of steel or alloy constrained by the holder 2 and fixed.

  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.

  Here, according to the present invention, as shown in 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 with respect to the longitudinal direction. By fixing the inclined rear end face 10 in contact with a cylindrical locking member 12 attached to the holder 2, the cutting blade 6 can be positioned and mounted with high accuracy even when the chip 4 is replaced. In addition, since the tip 4 can be firmly restrained, it is possible to prevent the tip 4 from rotating during cutting and the position of the cutting edge 6 from being displaced or the tip 4 from being loosened.

  In addition, according to the present invention, as shown in FIGS. 1 and 2, in addition to the restraint on the rear end face 10, a notch-shaped restraint portion processed to restrain the chip 4 on the side surface of the shank member 8. 14 is a major feature. As shown in FIG. 1, the restraining portion 14 has an auxiliary restraining force by inserting the screw member 15 directly on the side surface of the holder 2 and bringing it into contact with the restraining portion 14. As a result, the binding force and the mounting position accuracy of the chip 4 can be further ensured.

  According to FIG. 2, 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 FIGS. 1 and 2, the cutting edge 6 of the chip 4 is processed using the same jig as the holder 2 having the locking member 12 in the cutting edge processing step when manufacturing the chip 4. This makes it possible to process a chip with high dimensional accuracy.

  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, the cutting oil can be supplied from a position closer to the cutting edge 6 and the cutting oil can be applied to the cutting edge 6 efficiently and surely, cutting can be performed easily and the tool life can be extended. The chip discharge performance is improved, and the machined 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. 3, it is desirable that the tip 4 has a shape with a circular cross section of the insertion member 7 (rod-like portion) including the tip of the cutting edge 6 in view of easy manufacturing. Further, the side surface following the cutting edge 6 of the insertion member 7 is processed into a taper shape or a curved surface shape in FIG. 3 (a) in terms of preventing 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 insertion member 7 (rod-shaped portion).

  Furthermore, according to FIG. 4, 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 to each other. One chip 18 can have two cutting edges, and one chip 4 can double the cutting process.

  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 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, 6 'Cutting blade 7, 7' Insert member 8 Shank member 9, 9 'Insert hole 10 Rear end surface 12 Locking member 13, 15 Screw member 14 Restraint 16 Oil hole

Claims (6)

In a throw-away tip having a substantially rod shape and having a cutting edge protruding laterally from the circumferential surface of the rod-like portion at the longitudinal tip, the rear end surface of the throw-away tip has a length from the tip with respect to the longitudinal direction. A throw-away tip, wherein the throw-away tip is formed to be partially different, and a restraining portion for restraining the throw-away tip is provided on a side surface of the throw-away tip. At least the cutting blade is formed of an insertion member made of a hard alloy, and the rear end portion of the insertion member is provided in a shank member made of steel or alloy whose side and rear end surfaces are restrained by the tool holder. 2. The throw-away tip according to claim 1, wherein the throw-away tip is inserted and fixed in the insertion hole. The throw-away tip according to claim 2, wherein the insertion member is press-fitted and fixed in the insertion hole 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 and fixed in insertion holes provided at both ends of the shank member. The cutting tool formed by restraining the side surface and rear end surface of the throw-away tip according to any one of claims 1 to 5 to the tool holder.

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