JP2008279682A - Cone - Google Patents

Abstract

Provided is a cone that eliminates twists and maintains machining accuracy, and is versatile with reduced cost.
A cone 10 includes a flute screw hole formed at a tip portion of a flute portion 40, a bolt fastened to a flute screw hole through a through hole penetrating the center portion of the blade portion 30, a blade portion 30 and a flute portion 40. And a stop portion (concave portion 33 and convex portion 41) that is provided on one or both of the contact surfaces that face each other and stop the cutter portion 30 from rotating relative to the flute portion 40, and the diameter of the cutter portion 30. The center cone 20 has a small diameter and has a tip protruding beyond the tip of the blade portion 30 and attached to a through hole of the blade portion 30 in a replaceable manner. Since the flute screw hole is formed in the flute portion 40, it is possible to eliminate the twist and maintain the processing accuracy. Since it fastens using a volt | bolt separately from the blade part 30, cost can be restrained and versatility can be given.
[Selection] Figure 1

Description

  The present invention relates to a woodwork and a cone used for machining similar to woodwork, and relates to a cone having a flute portion for discharging chips and a blade portion attached to the tip of the flute portion in a replaceable manner.

A conventional cone provided with a flute portion and a blade portion is disclosed in, for example, Patent Documents 1 and 2 below. The cone (1) described in Patent Document 1 forms a columnar bifurcated portion (27, 28) at the tip of the flute portion (2), and the shank (10) of the blade portion (3) between the bifurcated portions. And is fixed with screws (16, 17) from both side surfaces of the bifurcated portion.
European Patent Application No. 1359879

The cone (10) described in Patent Document 2 has a flute screw hole (26) formed at the tip of the flute portion (20), a bolt (36) formed in the blade portion (30), and the bolt (36). It is fixed by screwing into the flute screw hole (26).
US Patent Application Publication No. 2001/0031178

  However, the cone (1) described in Patent Document 1 fixes the blade part (3) to the bifurcated part (27, 28). Since the bifurcated portion has a columnar shape thinner than the flute portion (2), the rigidity is greatly reduced. Therefore, when cutting a work (work) having a large cutting load, the bifurcated portion is easily twisted. When the bifurcated portion is twisted, not only the bifurcated portion is fatigued, but also the cutting accuracy is deteriorated because the position of the blade portion (3) is shifted.

  Since the cone (10) described in Patent Document 2 has the flute screw hole (26) formed at the tip of the flute portion (20), the above-described twist problem does not occur. However, the blade portion (30) is not only costly because the bolt (36) must be integrally formed, but also on the flute portion other than the flute portion (20) in which the flute screw hole (26) is formed. Can not be fixed.

  The present invention has been made in view of these points, and an object of the present invention is to provide a cone having generality at a reduced cost while maintaining processing accuracy by eliminating twisting.

(1) Means for solving the problem (hereinafter simply referred to as “solution means”) 1 is a rotary cutting having a flute portion for discharging chips and a blade portion that is replaceably attached to the tip of the flute portion. A flute screw hole formed at the tip of the flute part, a bolt that is fastened to the flute screw hole through a through hole that passes through the center part of the blade part, and the blade part and the flute part. It is provided on one or both of the surfaces that can be opposed to each other, and includes a rotation stop portion that prevents the blade portion from rotating with respect to the flute portion, a diameter smaller than the diameter of the blade portion, and a tip end of the blade portion. And having a central cone that protrudes from the tip of the blade and is replaceably attached to the through hole of the blade part.

  According to the solving means 1, when attaching a blade part to a flute part, it fastens with the flute screw hole formed in the front-end | tip part of a flute part using a volt | bolt. Thus, since the flute screw hole is formed in the flute portion, it is possible to maintain the processing accuracy by eliminating the twist together with the point that the rotation stop portion prevents the cutter portion from rotating relative to the flute portion. Moreover, since it fastens using a volt | bolt separately from a blade part, it is not necessary to integrally form a volt | bolt in a blade part. Although it is necessary to form a through hole for passing a bolt in the blade part, the cost can be reduced compared to forming a bolt in the blade part itself. Since the bolt corresponding to the diameter of the flute screw hole formed in the flute portion may be used, a blade portion having various diameters can be attached to one flute portion, and versatility can be provided.

(2) The solving means 2 is the cone described in the solving means 1 and is characterized in that the central axis of the flute screw hole is decentered with respect to the central axis of the flute portion.

  According to the solution 2, the central axis of the flute portion coincides with the central axis of the entire cone, but the central axis of the flute screw hole is decentered and therefore does not coincide with the central axis of the entire cone. Even if the cone is rotated during cutting or the like, the bolt is not easily affected by the inertia at the time of rotational fluctuation of the rotary drilling tool, so that the fastening force with the flute screw hole is difficult to decrease. Therefore, the bolt can be prevented from loosening from the flute screw hole.

(3) The solving means 3 is the cone described in the solving means 1 or 2, and is formed on one of the faces of the bolt head and the shank end of the central cone facing each other, and has a large planar shape. The gist is that the concave portion formed into a square shape and the convex portion formed on the other surface can be fitted.

  According to the solution 3, as a first form, a concave portion is formed on the head of the bolt, and a convex portion is formed on the shank end of the central cone. Moreover, as a 2nd form, a convex part is formed in the head part of a volt | bolt, and a recessed part is formed in the shank edge part of a center cone. In any form, since the concave portion and the convex portion are fitted, it is possible to prevent the central cone from rotating with respect to the blade portion due to cutting resistance generated during cutting. Therefore, cutting can be performed with the flute portion and the central cone more integrated.

(4) Solving means 4 is the cone described in any one of solving means 1 to 3, and is the cone described in solving means 4, wherein the bolt rotates in a direction opposite to the rotation direction of the central cone. The gist is that it is configured to be fastened with the flute screw hole.

  When the center cone cuts the workpiece, a cutting resistance is generated in a direction opposite to the rotation direction of the center cone. According to the solution means 4, the rotational force accompanying the cutting force is transmitted to the bolt to increase the fastening force with the flute screw hole (in other words, to make it difficult to loosen), thereby further integrating the blade portion and the flute portion. be able to.

  According to the present invention, since the flute screw hole is formed at the tip of the flute portion, the processing accuracy can be maintained without twisting. Moreover, since it fastens using a volt | bolt separately from a blade part, cost can be held down and versatility can be given.

  The best mode for carrying out the present invention will be described with reference to the drawings.

  In FIG. 1, the structural example of a cone is represented with a perspective view. The cone 10 includes a center cone 20 for improving straightness, a flute portion 40 for discharging chips, a blade portion 30 attached to the tip (lower left side in the drawing) of the flute portion 40 in a replaceable manner. For the center cone 20, for example, an iron drill or a woodwork cone is used. The blade part 30 plays the role of cutting the workpiece with the cutting blade 31, and chips generated by the cutting are discharged through the connection discharge groove 32 and the chip discharge groove 42 of the flute 40. In addition to the chip discharge groove 42, the flute portion 40 has a convex portion 41 corresponding to one side of the rotation stop portion, a shank 43 to be attached to a machine tool or the like. The diameter of the blade part 30 and the flute part 40 is arbitrary and is, for example, 32φ. The central cone 20 has a diameter smaller than the diameter of the blade part 30 or the like.

  A configuration example of the central cone 20 and the flute portion 40 will be described later, and a configuration example of the blade portion 30 will be described first with reference to FIGS. In FIG. 2, the structural example of the blade part 30 is represented with a perspective view. FIG. 3 shows a plan view of the blade part 30 viewed from the center cone side, and FIG. 4 shows a plan view of the blade part 30 viewed from the flute part side. FIG. 5 shows a side view of the blade part 30, and FIG. 6 shows a sectional view taken along the line VI-VI in FIG.

  A plurality of (two in this example) cutting blades 31 are attached to the blade portion 30 at predetermined positions on the distal end side (lower left side in the drawing) so as to be individually replaceable. In this predetermined position, a recess is formed in accordance with the outer shape of the cutting blade 31. The blade part 30 is provided with two tool mounting screw holes 34 (specifically, female screw holes) at two locations, and a small hole 31 c is formed in the approximate center of the cutting blade 31. The two cutting blades 31 are respectively attached to the blade part 30 by screwing the male screw 39 into the small hole 31c and the blade attachment screw hole 34. The cutting blade 31 is formed in a polygonal shape (rectangular shape in this example), and blade portions 31a and 31b are formed on two opposite sides of the rectangular shape. Even if one blade part (for example, the blade part 31a) is worn or damaged as the workpiece is cut, the male screw 39 is once loosened, the cutting blade 31 is rotated 180 degrees, and the male screw 39 is screwed again. Can be cut with the other blade (for example, blade 31b).

  In addition to the above-described blade mounting screw hole 34, the blade portion 30 has a connection discharge groove 32, a recess 33, a through hole 35 (see FIGS. 3, 4 and 6), and a step portion 36 (see FIG. 6). , A cylindrical portion 37 (see FIGS. 4, 5, and 6), a center cone fixing screw hole 38, and the like. As described above, the connection discharge groove 32 is a groove for discharging chips. As shown in FIG. 1, since the connection discharge groove 32 is connected to the chip discharge groove 42 of the flute portion 40, the spiral groove is formed in two lines like the chip discharge groove 42. The concave portion 33 corresponding to the other side of the rotation stop portion can be set arbitrarily (two in this example), and is provided on the facing surface 3 </ b> A facing the flute portion 40. This recessed part 33 fits with the convex part 41 of the flute part 40 which is one side of a rotation stop part (refer FIG. 1). The recess 33 is formed by, for example, keyway processing.

  A through hole 35 for passing a bolt 50 (for example, a cap bolt; see FIG. 7) is formed along the central axis of the blade part 30. The step portion 36 is formed in a part of the through hole 35 and plays a role of locking the head portion 52 of the bolt 50. The cylinder part 37 is provided on the flute part side (right side of the drawing) of the blade part 30 (see FIG. 8). The center cone fixing screw hole 38 is a female screw hole for fixing the center cone 20 passed through the through hole 35 with the male screw 23 (see FIG. 9).

  A configuration example of the flute portion 40 and a process of attaching the blade portion 30 to which the cutting blade 31 is mounted to the flute portion 40 will be described with reference to FIG. First, a configuration example of the flute unit 40 will be described. The flute part 40 has a convex part 41 and a flute screw hole 44 in addition to the chip discharge groove 42 and the shank 43 described above. The convex portions 41 corresponding to one side of the rotation stop portion are installed in a number corresponding to the concave portions 33 described above, and are provided on the facing surface 4 </ b> A facing the blade portion 30. The facing surface 4A can contact the facing surface 3A described above. The convex portion 41 is formed by keyway processing similarly to the concave portion 33 described above.

The flute screw hole 44 is a female screw hole that is formed along the central axis C of the flute 40 from the facing surface 4 </ b> A. Specifically, it is formed, for example, by tapping, and has a stepped portion 44a (see FIG. 8). The diameter of the cylinder part 37 described above is a size that just fits into the stepped part 44a.
In addition, in order to improve the chip | tip discharge | emission property, it is desirable to give the flute part 40 special coating (for example, fluororesin processing etc.).

A process of attaching the blade part 30 to which the cutting blade 31 is mounted to the flute part 40 will be described. The cylindrical portion 37 of the blade portion 30 may be inserted into the step portion 44a of the flute screw hole 44, and the bolt 50 may be screwed into the flute screw hole 44 after passing through the through hole 35 of the blade portion 30 and fastened. Since the bolt 50 of this example is fastened using a wrench (for example, a hexagon wrench), a concave portion 51 having a polygonal plane (for example, a hexagon) is formed in the head 52. The state after attaching the blade part 30 to the flute part 40 using the bolt 50 in this way is shown in FIG.
In this example, the flute screw hole 44 is formed along the central axis C of the flute 40. However, the flute screw hole 44 may be formed at a position eccentric from the central axis C. In this case, it is necessary to match the central axes of the through hole 35 and the bolt 50 along the central axis of the flute screw hole 44.

  Finally, the process of attaching the central cone 20 will be described with reference to FIG. As shown in FIG. 9, when the central cone 20 is inserted into the through hole 35 of the blade part 30, the process proceeds until it hits the head 52 of the bolt 50. Then, after the two male screws 23 are respectively screwed into the center cone fixing screw holes 38, the fastening operation is performed until the center cone fixing screw holes 38 abut against the center cone 20 and are pressed. A state after the central cone 20 is attached using the male screw 23 is shown in FIG. As is apparent from FIG. 10, the center cone main body 21 is attached so that the tip end protrudes beyond the tip end of the blade part 30.

  When the entire cone 10 is assembled in this way, the state shown in FIG. 1 is obtained. A member that is worn or damaged as a workpiece (for example, wood) is cut with the cone 10 can be replaced as follows. First, when the cutting blade 31 is replaced, the male screw 39 is loosened, the cutting blade 31 is removed, the new cutting blade 31 is placed at a predetermined position, and the male screw 39 is screwed in again and fastened. When replacing not only the cutting blade 31 but also the entire blade portion 30, the bolt 50 is loosened to remove the blade portion 30, and the cylindrical portion 37 of the new blade portion 30 is inserted into the step 44a of the flute screw hole 44, and again. The bolt 50 may be fastened by screwing into the flute screw hole 44 after passing through the through hole 35 of the blade part 30. When exchanging the central cone 20, the male screw 23 is loosened, the central cone 20 is taken out, the new central cone 20 is inserted, and then the male screw 23 is screwed again and fastened.

According to the embodiment described above, the following effects can be obtained.
(1) The blade part 30 was attached to the flute 40 by fastening with a flute screw hole 44 formed at the tip of the flute 40 using a bolt 50 (see FIG. 7). As described above, since the flute screw hole 44 is formed in the flute portion 40, the processing accuracy can be maintained without twisting. Further, since the bolt 50 is used separately from the blade part 30, it is not necessary to integrally form the bolt 50 on the blade part 30. Although it is necessary to form the through-hole 35 for passing the bolt 50 in the blade part 30, the cost can be reduced as compared with forming the bolt in the blade part 30 itself. Since the bolt 50 corresponding to the diameter of the flute screw hole 44 formed in the flute portion 40 may be used, the blade portion 30 having various diameters can be attached to the one flute portion 40, and versatility is provided. be able to.

(2) The cutting blade 31 was mounted on the blade portion 30 by screwing the male screw 39 into the small hole 31c and the blade mounting screw hole 34 (see FIG. 2). The cutting blade 31 is worn or damaged as the workpiece is cut. However, since the cutting blade 31 can be exchanged at any time, the cutting can be performed with a desired processing accuracy. Further, since the cutting blade 31 is formed in a polygonal shape (in this example, a quadrangular shape) and the blade portions 31a and 31b are provided on two sides, the cutting blade 31 is used until all the blade portions 31a and 31b are worn or damaged. Therefore, the life of the cutting blade 31 can be extended.
In this example, the blade portions 31a and 31b are provided on the two sides of the quadrangular cutting blade 31, but the blade portions may be provided on three sides or all sides. As the number of blades increases, the life of the cutting blade 31 can be extended.

(3) When the center axis of the flute screw hole 44 is decentered with respect to the center axis C of the flute 40, the center axis of the flute screw hole 44 is decentered. Does not match. Even if the cone 10 is rotated during cutting or the like, the bolt 50 is not easily affected by the inertia when the rotary drilling tool rotates, so that the fastening force with the flute screw hole 44 is not easily reduced. Therefore, the bolt 50 can be prevented from loosening from the flute screw hole 44.

[Other Embodiments]
Although the best mode for carrying out the present invention has been described above, the present invention is not limited to this mode. In other words, various forms can be implemented without departing from the scope of the present invention. For example, the following forms may be realized.

(1) In the embodiment described above, the shank 22 of the central cone 20 has a flat end portion (see FIG. 8). Instead of this configuration, a convex portion that fits into the concave portion 51 provided in the head portion 52 of the bolt 50 may be provided at the end portion of the shank 22. For example, as shown in FIG. 11, a convex portion 24 (the planar shape is, for example, a hexagon) is provided at the end of the shank 22. If comprised in this way, since the recessed part 51 and the convex part 24 will fit after attaching and fixing the center cone 20, it prevents that the center cone 20 rotates with respect to the blade part 30 by the cutting resistance which arises at the time of cutting. can do. Therefore, the flute 40 and the central cone 20 can be further integrated to perform cutting. Contrary to the configuration described above, a similar effect can be obtained by providing a convex portion on the head 52 and providing a concave portion on the end of the shank 22. Furthermore, even if a member in which the central cone 20 and the bolt 50 are integrated (that is, the end of the shank 22 is extended to form a thread similar to that of the bolt 50), the same effect can be obtained. .

  Each screw thread for the bolt 50 and the flute screw hole 44 is preferably formed so as to be fastened to the flute screw hole 44 when the bolt 50 is rotated in the direction opposite to the rotation direction of the central cone 20. According to this configuration, when the central cone 20 cuts the workpiece, a cutting resistance is generated in a direction opposite to the rotational direction of the central cone 20, but the rotational force accompanying the cutting resistance is applied from the central cone 20 to the bolt 50. It is transmitted and the fastening force with the flute screw hole 44 is increased. Therefore, the bolt 50 and the flute screw hole 44 are difficult to loosen, and the blade part 30 and the flute part 40 can be more integrated even during cutting.

(2) In the above-described embodiment, the shank 22 constituting the central cone 20 is formed in a round bar shape (that is, the cross section is circular) (see FIG. 11). Instead of this form, as shown in FIG. 12, a flat portion 25 (two surfaces facing each other) may be provided on a part of the shank 22. According to this configuration, the tip of the male screw 23 screwed into the center cone fixing screw hole 38 presses and fastens the flat surface portion 25, thereby preventing the shank 22 from rotating with respect to the blade portion 30. Can do. Thus, since the rotation (in other words, rattling) of the shank 22 is prevented, the processing accuracy by the cone 10 can be maintained.
Further, the shank 22 may be formed in a square bar shape (that is, the cross section is a polygonal shape). Even in this case, rotation can be prevented by fastening the male screw 23. When the through hole 35 of the blade part 30 is formed corresponding to the square bar shape, rotation can be prevented regardless of the presence or absence of the male screw 23.

(3) In embodiment mentioned above, it was set as the structure which mounts the cutting blade 31 with respect to the blade part 30 so that replacement | exchange is possible (refer FIG. 2). It is good also as a structure which replaces with this form and fixes the cutting blade 31 to the blade part 30 so that replacement | exchange is impossible. For example, the structure which brazes a cutting blade to the blade part 30, and the structure which forms integrally in the blade part 30 including a cutting blade correspond. Although the cutting blade cannot be replaced, it is possible to maintain the processing accuracy by eliminating the twist, and to provide versatility with reduced cost.

(4) In the above-described embodiment, the rotation stop portion is configured by the concave portion 33 provided on the facing surface 3A on the blade portion 30 side and the convex portion 41 provided on the facing surface 4A on the flute portion 40 side (FIG. 1). , See FIG. Instead of this form, the unevenness may be provided on the opposite facing surface, or a rotation stop may be provided on either the blade part 30 side or the flute part 40 side. About the latter, when providing in the blade part 30 side, for example, 3 A of opposing surfaces are formed so that it may fit in the external shape of 4 A of opposing surfaces without the convex part 41. FIG. Alternatively, the facing surface 4A is formed so as to be fitted to the outer shape of the facing surface 3A having no recess 33. Whatever the configuration, the blade part 30 can be prevented from rotating with respect to the flute part 40.

It is a perspective view showing the example of composition of a cone. It is a perspective view showing the structural example of a blade part. It is a top view (center cone side) showing the structural example of a blade part. It is a top view showing the example of composition of a blade part (flute part side). It is a side view showing the structural example of a blade part. It is sectional drawing of the VI-VI line represented in FIG. It is a perspective view explaining the process of attaching the structural example of a flute part, and a blade part to a flute part. It is sectional drawing showing the state which attached the blade part to the flute part. It is a perspective view explaining the process of attaching a center cone. It is sectional drawing showing the state which attached the center cone. It is a perspective view showing the 2nd structural example of a center cone. It is a perspective view showing the 3rd structural example of a center cone.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 cone 20 center cone 21 center cone main body 22 shank 23 male screw 24 convex part 25 plane part 30 blade part 31 cutting blade 31a, 31b blade part 32 connection discharge groove 33 recessed part 34 screw hole for blade attachment 35 through hole 36 step part 37 Cylindrical portion 38 Center cone fixing screw hole 39 Male screw 3A Opposing surface 40 Flute portion 41 Convex portion 42 Chip discharge groove 43 Shank 44 Flute screw hole 44a Step portion 4A Opposing surface 50 Bolt 51 Recessed portion 52 Head portion 53 Bolt body

Claims (4)

A cone having a flute portion for discharging chips and a blade portion attached to the tip of the flute portion in a replaceable manner,
A flute screw hole formed at the tip of the flute,
A bolt fastened to the flute screw hole through a through-hole penetrating the center of the blade part;
The blade part and the flute part are provided on one or both of the surfaces that can be opposed to each other, and a rotation stop part that stops the blade part from rotating with respect to the flute part;
A cone having a diameter smaller than the diameter of the blade part and having a central cone that is attached to the through hole of the blade part in a replaceable manner with a tip protruding beyond the tip of the blade part. The cone according to claim 1,
A cone in which the central axis of the flute screw hole is eccentric with respect to the central axis of the flute. The cone according to claim 1 or 2,
Of the surfaces where the head of the bolt and the shank end of the central cone face each other, the concave portion formed on one surface and having a polygonal planar shape can be fitted with the convex portion formed on the other surface Constructed cone. The cone according to any one of claims 1 to 3,
The bolt is a cone configured to rotate in the direction opposite to the rotation direction of the central cone and fasten with the flute screw hole.

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