JP6210276B2 - Throw-away cutting tool - Google Patents

Description

  The present invention relates to a throw-away cutting tool such as a milling cutter, broach, or metal saw in which a large number of cutting tips such as cemented carbide tips are arranged.

  The tip of the throw-away cutting tool is fixed to the tool body by brazing the tool body or screwing it to the tool body. In many cases, the insert is attached to a pocket or groove provided in the tool body. The height direction of the chip is regulated by the bottom (lower) surface of the pocket holding the chip, and the front-rear direction is positioned by the support surface in the longitudinal direction (circumferential direction) of the pocket.

  For example, in Patent Document 1, a wedge-shaped piece that fits a chip into a plurality of pockets provided in a long main body is fixed to the main body via a spring, and the chip is fixed by applying a wedge action with a predetermined force. . A plurality of vertical grooves are provided on the vertically long back surface of the chip. A V-shaped groove is provided on the vertically long front side of the chip. A cutting edge is formed at the upper part of the short side of the chip, and a receiving part is provided below the short side. In addition, the upper and lower short sides of the chip are inclined so as to spread toward each other in the back direction.

  The bottom of the chip short side is brought into contact with the bottom surface of the chip on the bottom of the pocket and the back surface of the chip is brought into contact with the support surface in the longitudinal direction of the pocket, and the V-shaped convex portion of the wedge piece is fitted into the V-shaped groove on the front of the chip. . An escape portion is provided so that the front and rear ends of the lower part of the short side of the chip do not interfere with the tool body. Moreover, it is also possible to provide cutting edges in the same direction on both the upper and lower sides of the short side of the chip, and it can be mounted upside down.

  In addition, as an example of a disk shape in which the fixing method is further simplified, in Patent Document 2, a V-shaped groove is provided on the main body side, a V-shaped convex portion is provided on the vertically long back surface of the chip, and the chip is directly attached with a bolt. It is fixed.

  On the other hand, in Patent Document 3, a large number of chips having a center hole coaxially aligned with a screw hole in the perpendicular direction of the elongated body are arranged in the longitudinal direction, and bolts penetrating the center hole are screwed into the screw holes to insert the chips. It is fixed. In this case, the direction of the cutting edge of the tip described above is not the same direction, the direction of the cutting edge is opposite, and a pair of cutting edges having a notch surface and a rake face are formed symmetrically in the center hole. . Longitudinal inserts are held by contacting the inserts arranged adjacent to the bolts passing through the center hole, and bringing the lower notch with the unused cutting edge into contact with the bottom of the tool body. It is a reception surface.

JP-A-11-320248 Japanese Utility Model Laid-Open No. 05-074726 JP-A-60-146618

  However, in the rod-shaped chip in which the cutting edges of Patent Documents 1 and 2 are on the same side, the rake face side is always the receiving surface of a fixing member such as a piece or a bolt. For this reason, the precision fall by the damage | wound and biting by processing waste may arise. In addition, there is a problem that the cutting edge is always on the exposed side, and chipping is likely to occur, and handling is necessary.

  Therefore, as in Patent Document 3, it is preferable to provide a notch surface and a cutting edge symmetrically about an axis (point). However, since the notch surface is brought into contact with the bottom surface of the tool body, a contact area must be ensured. For this reason, there existed a problem that the length of the longitudinal direction of a notch surface will become large. Further, since it is necessary to provide V-shaped grooves or projections on both sides, there are problems such as complicated processing on the support surface side of the pockets and pieces, and the need for position adjustment. SUMMARY OF THE INVENTION In view of such problems, the object of the present invention is a multi-cutting blade that is easy to handle while ensuring the advantages of a rod-shaped tip, being less affected by scratches and bites due to processing scrap, having a compact size in the longitudinal direction. It is an object of the present invention to provide a throw-away type cutting tool that has the above-mentioned tip, can be easily processed, and can ensure positional accuracy.

In the present invention, a substantially rectangular parallelepiped tip having a cutting edge and a rake face on two surfaces facing each other, a cutting tool body having a plurality of pockets into which the tips are inserted, and in the pocket A throw-away type cutting tool comprising a clamp piece for fixing the inserted insert, wherein the cutting edge and the rake face are formed by cutting off an end of the insert on one side of the insert The chip, and a flat portion provided with a concave groove or a protrusion extending from the notch to the opposite side of the notch, and the chip. Another set of notches and flat portions are also formed on the other surface side, and the configuration on the other surface side is point-symmetric with the configuration on the one surface side with respect to the center portion of the chip, And the pocket of the cutting tool body Is provided with a convex portion or a concave groove that can be fitted and positioned with the concave groove or convex portion of the chip, and the concave groove or convex portion of the chip and the convex portion or concave groove of the pocket are engaged with each other. The above-mentioned problems have been solved by providing a throw-away cutting tool in which a tip is fixed by the clamp piece .

That is, the convex portion or concave portion provided in the pocket so as to be fitted and positioned with the concave groove or convex portion of the flat portion on one surface side of the tip having a notch and a cutting edge provided symmetrically with respect to the center portion of the tip. The chip is positioned with the groove . The wedge surface of the clamp piece is brought into contact with the flat portion on the other surface side of the chip, so that the chip can be securely fixed to the pocket. The flat part of the chip on the side fixed to the pocket is opposite to the cutting edge used for cutting, does not face the rake face side, and is not affected by chips. Further, the other cutting edge not used for cutting is opposite to the rake face side used for cutting, and is similarly not affected by chips or the like. In addition, since the chip is supported not on the notch surface but on the flat surface, it is not necessary to enlarge the notch of the chip . Furthermore, since it is not necessary to set it as a notch plane like patent document 3, it can also be set as the rake surface of an arc-shaped cross section.

  In the invention according to claim 2, a throw-away cutting tool is provided in which a plurality of the concave grooves or convex portions are formed on the flat portion. The concave groove or the convex portion can be positioned with the supporting surface to be fitted. Such a concave groove or convex part is not necessarily limited to one place.

Moreover, the concave groove or convex part should just be able to be positioned by fitting with the convex part or concave part of the support surface side (meshing an uneven part). Examples of the cross-sectional shape of the concave groove or convex portion include a semicircle (round), a trapezoid, and a triangle (V-shaped). There may be at least two simultaneous contact portions facing each other. From the viewpoint of processing and accuracy to be obtained, a triangular (V-shaped) cross section is preferable. Therefore, in the invention described in claim 3, the concave groove is a throw-away cutting tool having a V-shaped cross section.

Further, in the invention according to claim 4, a throw-away type in which a relief portion is provided in the cutting tool main body, and the relief portion is a relief portion that prevents the cutting edge of the chip inserted into the pocket from contacting the inner surface of the pocket. A cutting tool was used.

In the present invention, the convex portion provided in the pocket so as to be fitted and positioned with the concave groove or convex portion of the flat portion on one surface side of the chip having a notch portion and a cutting edge provided symmetrically with respect to the center portion of the chip. Since the chip is positioned by the groove or the groove and the flat surface is pushed and fixed by the wedge surface of the clamp piece, the positioning accuracy is also high. In addition, the flat part of the tip fixed to the pocket is the opposite side of the cutting edge used for cutting and does not face the rake face, and cutting edges that are not used for cutting are also used for cutting. Since it is opposite to the rake face side and is not affected by the chips, it does not cause a decrease in accuracy due to scratches or biting of the processed chips. Moreover, since the other cutting edge which is not used has little exposure degree, handling is also easy. The notch is small, and a rake face with an arcuate cross section can be easily obtained. Since it is not supported by the notch , the length in the longitudinal direction can be reduced.

  In the second aspect of the present invention, since a plurality of concave grooves or convex portions are provided, it is possible to increase the positioning and mounting accuracy of a chip having a wide width.

In the invention described in claim 3, since the cross-sectional shape of the groove is a V-shaped cross-section, the processing is simple and easy to obtain, and the assembly is also easy. Further, it is easy to process the wedge surface of the clamp piece corresponding to the flat portion of the chip .

In the invention according to claim 4, since the cutting tool body is provided with a relief portion so that the cutting edge of the chip to be inserted into the pocket does not come into contact with the inner surface of the pocket , Damage was prevented. In addition, the short side shape can be simplified, and the flank wear can be easily corrected by machining.

(A) of the throw-away tip which shows embodiment of this invention is a front view, (b) is a left view, (c) is a right view, (d) is a top view, (e) is a bottom view. . (A) which shows embodiment of this invention is a clamp piece, (b) is a perspective view of a throw away tip. (A) which shows embodiment of this invention is a fragmentary sectional view of the partial side surface of a throwaway type broach, (b) is a partial top view. It is a perspective view of the throw away tip which has a convex part showing a 2nd embodiment of the present invention. It is a partial top view corresponding to FIG.3 (b) of the throwaway type broach using the throwaway tip which has a convex part which shows 2nd embodiment of this invention. It is a partial top view corresponding to FIG.3 (b) of the throwaway type broach using the throwaway tip which has the partial circular convex part which shows 3rd embodiment of this invention. It is a perspective view of the throw away tip which has two V-shaped grooves which show a 4th embodiment of the present invention. (A) showing another embodiment of the present invention is a throwaway tip having a rake face having an arcuate cross section and a semicircular concave groove, and (b) is a semicircular shape having a cutting edge as a convex straight blade. (C) is a perspective view of a throw-away tip having a convex arcuate blade and having a trapezoidal groove.

  A first embodiment of the present invention will be described with reference to the drawings. The embodiment of the present invention is applied to a grooving broach for keyway cutting. FIG. 3 shows a part of the grooving broach. As shown in FIG. 3, the groove broach 1 is provided with a large number of pockets 2 in the longitudinal direction, and a large number of chips 3 are inserted into the pockets. On the basis of the broach (cutting tool) main body 11 of the inserted chip, the horizontal or height dimension of the cutting edge 4 is widened or raised for a while. The broach body 11 and the workpiece (not shown) are moved relative to each other in the longitudinal direction (the tool moves in the direction of the arrow), and gradually cut in the width and depth direction of the groove of the workpiece. Grooves are formed.

As shown in FIGS. 1 and 2B, the chip 3 according to the first embodiment of the present invention includes a notch 32 provided at one end of the chip 3 and a scoop provided at the notch 32. A surface 5 and a cutting edge 4 are formed. Further, a flat surface portion 30 is formed adjacent to the notch portion 32 . The flat portion 30 is provided with a V-shaped (concave) groove 34 along the ridge line 33 . The chip 3 is provided with two notches 32, a rake face 5, a cutting edge 4, and ridge lines 31 , 33 , with the center thereof being point-symmetric ( notch 32 ', rake face 5', cutting edge). 4 ', ridge lines 31', 33 ').

As shown in FIG. 3, the pocket 2 into which the chip 3 is inserted is provided with a first support surface 21 that supports the ridge line 33 of the chip 3 and a second support surface 22 that supports the ridge line 31 ′. A screw hole 23 is provided on the side opposite to the first support surface of the second support surface 22 or toward the center. The first support surface 21 forms a convex portion extending obliquely downward in a side view corresponding to the V-shaped concave groove 34 of the chip 3. Both sides 21 'of the first support surface 21 are flat. Note that both sides 21 ′ of the first support surface 21 may be arcs, slopes, or other shapes. Further, both sides 21 ′ of the first support surface 21 may be brought into contact with the flat portion 30 of the chip 3 , but since machining accuracy is required, it is preferable that the first support surface 21 is non-contact in order to ensure positioning performance. .

As shown in FIGS. 2A and 3, the clamp piece 24 has a wedge shape, and the wedge surface 25 abuts against the flat surface portion 30 ′ of the ridge line 33 ′ of the chip 3. The inclination of the wedge surface 25 is substantially the same as the inclination of the ridge line 33 ′ in a state where the chip 3 is supported by the first and second support surfaces 21 and 22 . A through hole 26 is provided in the center of the clamp piece 24 so as to face downward. The fixing bolt 27 is passed through the through hole 26 and screwed into the screw hole 23 to fix the clamp piece 24 to the broach body 11. The wedge surface 25 of the clamp piece 24 is a flat surface and abuts against the other flat surface portion 30 ′ of the chip 3. Further, the V-shaped groove 34 of one ridge line 33 of the chip 3 is fitted and positioned with the first support surface 21. Thereby, the positioning of the chip 3 in the width direction and the longitudinal direction is performed, and the chip 3 is fixed to the broach body 11.

3 as shown in the right part of (a), further, the pockets 2 and the other notch 32 'and the relief as ridge line 35 between the flat portion 30 does not contact portion 28, the other cutting edge 4 An escape portion 29 is provided so that 'does not contact. In addition, a third support surface 13 is provided between the relief portions 28 and 29 so as to abut against the rake surface 5 'on the other side.

Thereby, there is no influence of the cutting scraps on the cutting edge 4 ′ which is not provided for the point-symmetrical processing, and the work at the time of assembly becomes easy. In addition, positioning and dimension management on the first and second support surfaces 21 and 22 are facilitated. Furthermore, even if flank machining is performed by wear of the cutting edge, the ridgeline 31 'portion excluding the vicinity of the cutting edge is supported by the second support surface 22, so the influence of flank machining is small and the mounting accuracy is high. . Further, since the ridgelines 31 , 31 ′ are used as receiving surfaces, the longitudinal dimension can be shortened as compared with the case where the notched surfaces are used as receiving surfaces.

Next, a second embodiment of the present invention will be described with reference to the drawings. Note that parts similar to those described above are denoted by the same reference numerals, and part or all of the drawings and description are omitted. In the second embodiment of the present invention, convex portions are used instead of the V-shaped concave grooves of the flat portions 30, 30 'of the ridgelines 33, 33' of the chip described above. As shown in FIGS. 4 and 5, the flat portion 30 of the chip 3 is provided with a convex portion 34 along the longitudinal direction . On the other hand, the first support surface 21 of the pocket 2 is formed with a V-shaped groove extending obliquely downward in a side view corresponding to the convex portion 34 of one ridge line 33 of the chip 3. The convex portion 34 of one ridge line 33 of the chip 3 is fitted and positioned with the V-shaped concave groove of the first support surface 21.

As described above, the wedge surface 25 of the clamp piece 24 comes into contact with the flat surface portion 30 ′ of the other ridge line 33 ′ of the chip 3. A relief groove 37 having a square cross section is provided in the center of the wedge surface 25 of the clamp piece 24 so as not to interfere with the convex portion 34 ′ of the other ridge line 33 ′ of the chip 3.

The third embodiment of the present invention will be described with reference to the drawings. Note that parts similar to those described above are denoted by the same reference numerals, and part or all of the drawings and description are omitted. As shown in FIG. 6, in the third embodiment of the present invention, the shape of the relief groove 37 of the clamp piece 28 according to the second embodiment is a partial circular cross section. In this way, the wedge surface 25 of the clamp piece 24 abuts against the flat surface portion 30 ′ of the other ridge line 33 ′ of the chip 3 and does not interfere with the convex portion 34 ′ provided on the flat surface portion of the other ridge line. That's fine.

  Furthermore, a fourth embodiment of the present invention will be described with reference to the drawings. Note that parts similar to those described above are denoted by the same reference numerals, and part or all of the drawings and description are omitted. As shown in FIG. 7, the fourth embodiment of the present invention is an example in which a plurality of concave grooves 34, 34 ′ of the chip 3 of the first embodiment are provided. By providing a plurality, a wide chip can be positioned and fixed with high accuracy.

Furthermore, another embodiment of the present invention will be described with reference to the drawings. Note that part or all of the description of the same parts as described above is omitted. Since the notches 32 and 32 'are not used for the receiving surface or the like, they may have any shape. Therefore, the rake face 5 can be arcuate. FIG. 8A shows an example of a throw-away tip having a rake face 5 having an arcuate cross section and a semicircular concave groove 34 ′. Thereby, the discharge of chips becomes good. Thus, it became applicable to various rake surfaces.

  Further, what is shown in FIG. 8B is a throw-away tip having the cutting edge 4 as a convex straight edge and having semicircular convex portions 34 and 34 '. Furthermore, what is shown in FIG. 8C is a throw-away tip having a cutting edge as a convex arcuate blade and having trapezoidal concave grooves 34 and 34 '.

The arcuate blade may be concave. Moreover, it is good also as a convex part instead of a ditch | groove. Thus, the cutting edge shape and the rake face shape may be appropriately selected according to the object to be processed. Furthermore, various shapes can be applied to the convex portions or the concave grooves of the first support surface 21 that fit into the concave grooves or the convex portions 34, 34 'of the ridge lines 33, 33' of the chip 3. Moreover, although the long groove broach 1 was described, it cannot be overemphasized that it can apply suitably also to disk shaped broaches and disk-shaped throw-away type cutting tools, such as a saw and a mill.

1 Throw-away cutting tool (groove broach)
2 Pocket 3 Tip 4 (One) Cutting edge 4 '(Other) Cutting edge 5, 5' Rake face 11 Cutting tool (broach) body 21 First support face 22 Second support face 24 Clamp piece 28, 29 Relief part 30 (one long side) plane part 30 '(the other long side) plane part 31, 31' ridgeline 32, 32 'notch 33, 33' ridgeline 34 (one) concave groove or convex part 34 ' (Other) groove or protrusion 35 ridgeline

Claims (4)

A substantially rectangular parallelepiped tip having a cutting edge and a rake face on two surfaces facing each other, a cutting tool body having a plurality of pockets into which the tips are inserted, and the tip inserted into the pockets A throw-away type cutting tool comprising:
One side of the tip is a notch where the cutting edge and the rake face are formed by notching the end of the tip,
A flat portion provided with a groove or a convex portion extending from the end to the notch and extending to the opposite side of the notch, and
Another set of notches and flat portions are also formed on the other surface side of the chip,
The configuration on the other surface side is point symmetric with the configuration on the one surface side with respect to the center portion of the chip, and
The pocket of the cutting tool body is provided with a convex portion or a concave groove that can be fitted with the concave groove or convex portion of the chip,
The throw-away cutting tool , wherein the tip is fixed by the clamp piece in a state where the concave groove or convex portion of the tip and the convex portion or concave groove of the pocket are engaged with each other.       The throwaway cutting tool according to claim 1, wherein a plurality of the concave grooves or convex portions are formed in the flat portion. The throw-away cutting tool according to claim 1 or 2, wherein the concave groove has a V-shaped cross section . The cutting tool main body is provided with a relief portion, and the relief portion is the pocket.
The cutting edge of the tip inserted into the pocket does not come into contact with the inner surface of the pocket
The throw-away cutting tool according to claim 1, 2 or 3, wherein the throw-away cutting tool is an escape portion .

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