JP2005238369A - Throw-away type cutting tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensively manufacturable throw-away type cutting tool easy in adjusting a processing diameter. <P>SOLUTION: This throw-away type cutting tool 1 is formed by detachably installing a throw-away tip 5 on a tip installing seat 4 equipped in a tip part of a chip pocket 3 by forming the chip pocket 3 in a symmetric position of a holder tip part 11 to a holder rotary shaft 7. The cutting tool forms a slit 6 for dividing the holder tip part 11 into two parts and passing through the holder rotary shaft 7. A screw member 9 is inserted from a first holder tip part 11a of the holder tip part 11 divided by the slit 6. The screw member 9 is threadedly engaged with a second holder tip part 11b. A distance between slit inner wall surfaces 8 and 8' can be changed by the threaded movement of the screw member 9. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a throw-away type cutting tool used as a rotating tool in a machining center or the like, and more particularly to a throw-away type cutting tool for boring used for unrolling a hole drilled to a desired hole diameter.

  2. Description of the Related Art Conventionally, as a throw-away cutting tool for boring work used to unroll a hole drilled or the like to a desired hole diameter, for example, a cartridge having a cutting edge as shown in Patent Document 1 is provided. Thus, a cutting tool that enables adjustment of the machining diameter perspective is known. However, the configuration using such a cartridge has a problem that, as the adjustment is repeated, the sliding portion of the cartridge wears out, so that the sliding becomes irregular and an accurate hole diameter cannot be obtained. It was. In addition to the holder and the throw-away chip, a cartridge member must be separately prepared and assembled, resulting in a complicated structure and high cost.

On the other hand, there is known a configuration in which the machining diameter can be adjusted by directly attaching a throw-away tip to a tool holder without using the cartridge as described above and elastically deforming the holder (see, for example, Patent Document 2). With such a configuration, the adjustment member is less deteriorated, the adjustment mechanism is relatively simple, and can be manufactured at a low cost.
Japanese Utility Model Publication No. 6-61409 Special table 2003-511252 gazette

  However, in the configuration as disclosed in Patent Document 2, the position adjustment mechanism is provided for each throw-away tip, so that each position adjustment mechanism is adjusted alternately in order to obtain a desired hole diameter. However, there is a problem that it is necessary to align the cutting edge positions of a plurality of throw-away tips at the same distance from the center of the holder, and it takes time to adjust the cutting edge position. In addition, since the two slits are formed in the directions orthogonal to each other for each position of the holder corresponding to each throw-away tip, there is a problem that the holder rigidity is lowered and chatter is likely to occur during cutting. . Further, when the holder is broken due to overload or the like, there is a high possibility that the two slits will break and scatter from the weakest area where the two slits are close to each other.

  The present invention has been made to solve such a problem of the prior art, and in a throw-away type cutting tool used to unroll a hole drilled or the like to a desired hole diameter, An object of the present invention is to provide an inexpensive and highly safe throw-away cutting tool that can be easily adjusted in diameter and can be stably machined.

  In order to solve the above-described problem, the throw-away cutting tool of the present invention has two chip pockets formed at positions symmetrical to the holder rotation axis at the tip of the holder, and is provided at the tip of the chip pocket. A throw-away type cutting tool in which a throw-away tip is detachably attached to each of the tip mounting seats, and a slit is formed so as to divide the tip of the holder into two parts and pass through the rotation axis of the holder, A screw member is inserted from the first holder tip of the holder tip divided by the slit, the screw member is screwed to the second holder tip, and the inner wall surface of the slit is screwed by the screw member. It is characterized by the distance between them changing.

  According to such a configuration, the front end of the holder having the slit is elastically deformed by a mechanical operation such as the screwing of a single screw, so that the distance between the inner walls of the opposing slits can be adjusted. The processing diameter can be adjusted.

  Further, since the holder tip is only divided by a single slit perpendicular to the radial direction passing through the holder rotation axis, a decrease in rigidity of the holder is suppressed as compared to the case where a plurality of slits are formed. Furthermore, it has the structure which supplements holder rigidity by connecting the two holder parts divided by the slit with the screw.

  Furthermore, it is desirable that the screw member is rotatably fixed to the tip end portion of the first holder by a stopper. According to such a configuration, even when a force in a direction approaching the rotation axis is applied to the first holder tip portion due to a cutting load during cutting, the stopper fixes the first holder tip portion to the screw member. Therefore, it is desirable that the first holder tip is prevented from being reduced in diameter in a direction approaching the rotation axis, the interval between the inner walls of the slit is constant, and the machining diameter is constant regardless of the cutting load.

  In addition, since the slit is formed so as to communicate between the chip pockets, the length of the slit in the radial direction can be shortened as much as possible, so that a decrease in rigidity of the holder can be minimized. Is desirable.

  Further, the slit is formed so as to cross between the outer peripheral side surfaces of the holder tip without crossing the chip pocket. According to such a configuration, since the outer peripheral cutting edge position of the throw-away tip can be placed at a position farthest from the slit, the cutting blade position can be changed to the maximum by a small amount of elastic deformation of the holder. It is desirable in that the fatigue due to the deformation of the tip portion can be reduced, the deformation of the holder tip portion can be suppressed from plastic deformation, and the working diameter can be adjusted in a wider range.

  According to the throw-away cutting tool of the present invention, the chip pocket is formed at a position symmetrical to the holder rotation axis of the holder tip, and the throw-away tip is mounted on the chip mounting seat provided at the tip of the chip pocket. In the throw-away cutting tool in which the tool holder is detachably mounted, a slit is formed so that the tip end portion of the tool holder is divided in two and passes through the rotation axis of the holder, and the tip end portion of the holder divided by the slit is formed The screw member is inserted from the tip end portion of the first holder, and the screw member is screwed to the tip end portion of the second holder, and the distance between the inner wall surfaces of the slit is changed by the screwing of the screw member. This makes it possible to adjust the distance of the throw-away tip from the rotating shaft, that is, the machining diameter, with a simple structure with little decrease in holder rigidity. That.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 to 5 show a first embodiment of the present invention, and FIG. 1 shows a tip portion of a throw-away cutting tool (hereinafter abbreviated as a cutting tool) according to the first embodiment of the present invention. 2 is a side view as viewed in the direction of the slit in FIG. 1, FIG. 3 is a side view as viewed in the direction of the arrow A in FIG. 1, FIG. 4 is a bottom view of FIG. It is a bottom view which shows the state which closed.

  In FIG. 1, the cutting tool 1 according to the first embodiment of the present invention has a chip pocket 3 formed at a symmetric position with respect to the holder rotation shaft 7 at the tip of the holder 2, and at the tip of the chip pocket 3. A throw-away tip (hereinafter abbreviated as “chip”) 5 is detachably mounted on the provided chip mounting seat 4.

  As shown in FIG. 2, a slit 6 that divides the tip of the holder 2 into two is formed so as to pass through the rotation shaft 7 of the holder 2, and the holder tip 11 divided by the slit 6 The screw member 9 is inserted from a screw hole provided on one end side, that is, the side surface of the first holder tip portion 11a, and the screw member 9 is screwed to the other end side of the holder tip portion 11, that is, the second holder tip portion 11b. Match. Thus, although the holder front end portion 11 is divided by the single slit 6, since the two divided holder front end portions 11 are connected and reinforced by the screw member 9, the rigidity is reduced as much as possible. It has a suppressed structure.

  As shown in FIGS. 2 and 3, when the screw member 9 is tightened, the holder 2 is elastically deformed so that the distance between the inner wall surfaces 8 and 8 ′ of the slit 6 approaches. As a result, in conjunction with this, the outer peripheral cutting edge position of the tip 5 moves inward so as to approach the rotating shaft 7 of the holder, and as a result, the machining diameter of the cutting tool 1 can be adjusted. In this case, the distance between the opposing slit inner wall surfaces 8 and 8 ′ can be adjusted by elastically deforming the holder tip portion having the slit 6 by a mechanical operation of screwing the single screw member 9. It is possible to adjust the above-described processing diameter with a simple structure.

  Further, if the screw member 9 is rotatably fixed to the first holder tip portion 11a by a stopper 12, the screw member 9 approaches the rotary shaft 7 toward the first holder tip portion 11a due to a cutting load during cutting. Even when a force is applied, the stopper 12 fixes the first holder tip 11 a to the screw member 9, so that the first holder tip 11 a is reduced in diameter in a direction approaching the rotation shaft 7. This is desirable because the interval between the inner wall surfaces of the slit 6 is constant, and the machining diameter is constant regardless of the cutting load.

  Moreover, as shown in FIG. 4 or FIG. 5, since the slit 6 is formed between the chip pockets, the length L of the slit in the radial direction can be shortened as much as possible. Can be minimized.

  FIGS. 6 to 10 show a second embodiment of the present invention. FIG. 6 is a perspective view of the tip of a cutting tool according to the second embodiment of the present invention. FIG. FIG. 8 is a side view as viewed in the direction of arrow B, FIG. 8 is a side view as viewed in the direction of arrow C in FIG. 6, FIG. 9 is a bottom view of FIG.

  As shown in FIGS. 6 to 10, the cutting tool 21 according to the second embodiment of the present invention has a configuration in which a slit 26 is formed at a position not intersecting with the chip pocket 3, that is, at the outer peripheral side surface of the holder tip. ing. As shown in FIGS. 9 and 10, the outer peripheral cutting edge position of the tip 5 can be set to the longest position with respect to the inner wall surfaces 28, 28 ′ facing the slit 26, whereby the same holder tip 31 a, The cutting edge position of the tip 5 can be moved most greatly by the amount of elastic deformation 31b. This is desirable because it allows a wider range of machining diameter adjustment.

  As mentioned above, although embodiment of this invention was illustrated, this invention is not limited to embodiment mentioned above, It cannot be overemphasized that it can be made arbitrary, unless it deviates from the objective of invention.

  For example, in the present invention, in addition to the embodiment described above, two slits are formed from the respective chip pockets 3 across the outer peripheral side surface of the holder 2, and these two slits are respectively connected to the screws of the two screw members. It may be configured to adjust by movement to increase or decrease the distance of the tip from the rotating shaft, and the use (machining) form is not limited to boring, but as an end mill for shoulder machining and grooving It may be used.

It is a perspective view of the front-end | tip part of the throw away type cutting tool by 1st embodiment of this invention. It is a side view of the slit direction arrow of FIG. It is a side view of the A direction arrow of FIG. It is a bottom view of FIG. It is a bottom view which shows the state which the slit front-end | tip part in FIG. 4 closed. It is a perspective view of the front-end | tip part of the throw away type cutting tool by 2nd embodiment of this invention. It is a side view of the B direction arrow of FIG. It is a side view of the C direction arrow of FIG. FIG. 7 is a bottom view of FIG. 6. FIG. 10 is a bottom view showing a state in which a slit front end portion in FIG. 9 is closed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Throw away type cutting tool 2 Holder 3 Chip pocket 4 Chip mounting seat 5 Throw away tip 6, 26 Slit 7 Rotating shaft 8, 8 ', 28, 28' Inner wall surface 9 of the slit 6 Screw member 10 Divided tip of the holder Near the base 11 Holder tip 11a, 31a First holder tip 11b, 31b Second holder tip 12 Stopper L Length of the slit 6 across the holder 2

Claims (4)

Two chip pockets are formed at positions symmetrical to the holder rotation axis at the tip of the holder, and a throw-away tip is detachably attached to each chip mounting seat provided at the tip of the chip pocket. In the away-type cutting tool, a slit is formed in the holder tip so as to divide the holder tip into two parts and pass through the rotation axis of the holder, and the first holder tip of the holder tip divided by the slit The screw member is inserted from the portion, the screw member is screwed into the tip of the second holder, and the distance between the inner wall surfaces of the slit is changed by screwing of the screw member to rotate the throw-away tip. A throw-away type cutting tool characterized in that the distance from the shaft can be adjusted. The throw-away cutting tool according to claim 1, wherein the screw member is rotatably fixed to the distal end portion of the first holder by a stopper. The throw-away cutting tool according to claim 1 or 2, wherein the slit is formed so as to connect the chip pockets. The throw-away type cutting tool according to claim 1, wherein the slit is formed so as to cross between the outer peripheral side surfaces of the tip of the holder without communicating with the chip pocket.

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