JPH07241703A - Throw away tip for rotary bite and rotary bite - Google Patents

Abstract

PURPOSE:To provide a throw away tip for a rotary bite of which the manufacture is easy, the cost is low, and the coaxial degree of the tip is easily obtained, and a rotary bite using the tip. CONSTITUTION:A throw away tip 20 is constituted of a disc-like tip main body 22 of which the upper and lower faces 20a, 20b are formed into a circle in the contour by plan view and in parallel with each other and a through hole 21 is provided so as to pass on the center axis, and a shaft body 23 press fitted in the through hole 21 and fixed so that the end part is projected from at least one of the upper and lower faces 20a, 20b of the tip main body 22. A rotary bite 30 is provided with the throw away tip 20, and a tool main body 31 to which the throw away tip 20 is rotationally movably fitted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away tip for a rotary bite and a rotary bite provided with a throw-away tip for a rotary bite, which is driven by a body to be cut and rotates while cutting the body.

[0002]

2. Description of the Related Art Conventionally, in turning and boring systems, there are cutting tools used for machining the inside and outside diameters of a workpiece. As an example of this type of tool, for example, FIGS.
There is a cutting tool with a disc-shaped throw-away tip attached as shown in. In this cutting tool, a tip seat 2 which is, for example, a substantially rectangular recess in plan view is formed at the tip of a tool body 1, and a disc-shaped throwaway tip 4 is seated on a tip seat bottom surface 3. 4 is fixed by a lever 5 formed in an L shape. One end 6 of the lever 5 is inserted into a through hole 7 provided in the central portion of the throw-away tip 4 and the other end 8 of the lever 5 is inserted.
Is projected into a screw hole 9 formed at the tip of the tool main body 1, and a screw 10 is screwed toward the inner side of the screw hole 9 to rotate the whole body around a corner 11 as a fulcrum. The one end 6 strongly presses and restrains the throw-away tip 4 against the tip seat side wall surface 12.
Further, a locking claw 13 is provided at one end 6 of the lever 5, and the locking claw 13 is locked to a locking flange 14 projecting in the through hole 7 of the throw-away tip 4 to allow the throw-away. The away tip 4 is strongly attracted and constrained in the direction of the tip seat bottom surface 3 of the tool body 1. When the workpiece is cut, the cutting edge of the disk-shaped throw-away tip 4 fixed and held in this way is used for cutting, and when the cutting edge is worn or the cutting edge is broken, the lever The restraining force of the throw-away tip 4 by 5 is loosened, and the attachment angle position of the throw-away tip 4 is changed to perform cutting.

[0003]

By the way, in the above-mentioned conventional cutting tool, when the cutting portion of the throw-away tip 4 is worn, the cutting operation is stopped and the throw-away tip 4 is cut.
It is necessary to release the clamp, rotate the throw-away tip 4 by hand, and then re-clamp it, which causes a problem that continuous cutting cannot be performed. In addition, since the throw-away tip 4 is only partially worn, there is a problem that the wear rate is high and the continuous cutting time is short.

In view of the above problems, the present invention provides a throw-away tip for a rotary bite, which is easy to manufacture, low in cost, and capable of easily obtaining the coaxiality of the tip, and a rotary bite using the same. With the goal.

[0005]

In the throw-away tip for rotary bite according to the first aspect of the present invention, the tip is formed in a disk shape, and the ridge line of at least one of the peripheral surface and the upper and lower surfaces is a cutting edge. In a throw-away tip for a rotary bite that brings the cutting edge into contact with a rotating cutting object and cuts the cutting object while rotating following the cutting object, the contour in plan view is circular. And a disk-shaped chip body in which two surfaces facing each other are parallel to each other, and a through hole is formed so as to pass on the central axis thereof, and an end portion of the disk body in the through hole of the chip body. The shaft body is press-fitted and fixed so as to project from at least one of the upper and lower surfaces.

In the throw-away tip for rotary bite according to claim 2, in the throw-away tip according to claim 1, both ends of the shaft body project from the upper and lower surfaces of the tip body, respectively. Characterize.

According to a third aspect of the present invention, there is provided a rotary bite, which comprises the rotary bite insert for a rotary bite according to the first aspect and a tool main body to which the indexable tip is attached. It is characterized in that it is attached to the tool body so as to be rotatable around the body.

The rotary bite according to claim 4 comprises a throw-away tip for a rotary bite and a tool main body to which the throw-away tip is attached. The throw-away tip has two circular opposing contours in plan view. The surfaces are parallel to each other, a through hole is formed so as to pass on the central axis thereof, and a ridgeline of at least one of the peripheral surface and the upper and lower surfaces is formed into a disc shape having a cutting edge, and the tool body is A chip mounting portion for mounting the throw-away tip with its lower surface abutted, and the throw-away tip mounted on this chip mounting portion is clamped from the upper surface side thereof in cooperation with the chip mounting portion. A shaft portion that protrudes into the through hole of the throw-away tip and serves as a rotation axis of the throw-away tip is formed on either or both of the clamp member. And said that you are.

[0009]

In the throw-away tip for rotary bite according to the first aspect, the throw-away tip for rotary bite is used with its shaft portion rotatably held.

In the throw-away tip for rotary bite according to the second aspect, the shaft portion of the throw-away tip for rotary bite projects upward and downward, and the projecting portion of the shaft portion is rotationally held.

In the rotary cutting tool according to the third aspect, the shaft of the throw-away tip for the rotary cutting tool is rotatably supported by the tool body for use.

In the rotary bite according to the fourth aspect, the shaft portion of the throw-away tip for the rotary bite is rotatably supported and used in the chip mounting portion or the clamp member.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIGS. First, a throw-away tip for a rotary bite of the present invention (hereinafter simply referred to as "throw-away tip") will be described with reference to FIG.

In FIG. 1, reference numeral 20 is a throw-away chip of the present invention. This throw-away tip 20
Two surfaces 20a, 20 having a circular outline in plan view and facing each other
b is parallel to each other, and a disk-shaped chip body 22 in which a through hole 21 is formed so as to pass on the central axis thereof, and the through hole 21 of the chip body 22 has an end portion of the chip body 22. It has a shaft body 23 press-fitted and fixed so as to project from at least one of the upper and lower surfaces 20a and 20b.

The shaft 23 has a large-diameter portion 24 formed in an outer diameter corresponding to the through-hole 21 and having a cylindrical shape when viewed from the outside. The large-diameter portion 24 projects from both axial ends of the large-diameter portion 24 and has its own axis line. Is composed of the axis of the large diameter portion 24 and the small diameter portion 25 which is located on the same axis as the outer diameter of the cylinder. In the shaft body 23, the axial dimension of the large diameter portion 24 is the indexable tip 2
Since the thickness is 0, the axially opposite end surfaces 26, 26 of the large-diameter portion 24 are press-fitted into the through hole 21, so that the throw-away tip 20 has upper and lower surfaces 20a, 20a.
20b, and only the small-diameter portions 25, 25 have the upper and lower surfaces 20.
It projects from a and 20b. In addition, the upper and lower surfaces 20a and 20b of the chip body 22 and the chip body 2
Each ridgeline with the outer peripheral surface 20c of the second side forms a cutting edge 27.

The rotary bite 30 which holds the throw-away tip 20 in rotation will be described below. Figure 2
As shown in FIG. 3, the rotary bite 30 includes the throw-away tip 20 and a tool body 31 to which the throw-away tip 20 is attached, and the throw-away tip 20 is centered on the central axis of the tip body 22. It is rotatably attached to the tool body 31. In the tool body 31, a notch 34 is formed by notching a tip surface 33 of a protrusion 32 formed at the tip, and one corner of the notch 34 is further notched in a fan shape in plan view, A tip seat 35 on which the throw-away tip 20 is placed is formed.

As shown in FIG. 3, a concave portion 36 having a circular cross section is formed on the bottom surface of the tip seat 35, and the concave portion 36 has a substantially columnar shape having a collar portion 37 having substantially the same diameter as the throw-away tip 20. The seat portion 38 is fitted and the collar portion 37 is seated on the bottom surface of the tip seat 35. The seat part 3
8, a lower shaft hole 39 is formed in the center of the surface of the collar portion 37 of the shaft body 8, and the shaft body 2 of the throw-away tip 20 is formed in the lower shaft hole 39.
The throw-away tip 20 is seated on the collar portion 37 by rotatably fitting the small-diameter portion 3 of 3.

A clamp breaker 40 is fitted in the cutout portion 34 of the front end surface 33, and is fixed by a clamp screw 41. A part of the clamp breaker 40 extends to a region of the upper surface 20a of the throw-away tip 20 placed on the tip seat 35, and an upper shaft on which the shaft body 23 of the throw-away tip 20 is rotatably fitted. A pressing portion 43 having a hole 42 is formed, and the throw-away tip 20 is pressed by this pressing portion 43.

A cylindrical brake collar 45 having a U-shaped cross section is provided between the clamp breaker 40 and the head 44 of the clamp screw 41. Clamp breaker 4
A hole 46 is formed in the peripheral region of the clamp screw 41 of 0, and the clamp screw 4 is formed in the hole 46.
An annular collar 47 having a T-shaped cross-section through which 1 passes is arranged,
The upper end thereof is in contact with the lower surface of the brake collar 45. A brake washer 48 is fitted and arranged on the upper surface of the clamp breaker 40 on the outer periphery of the annular collar 47, and a wave washer 49 is interposed between the brake washer 48 and the brake collar 45 in a compressed state. There is.

A cylindrical stepped recess 50 is formed around the clamp screw 41 of the cutout portion 34 of the protrusion 32, and the collar portion of the annular collar 47 is located in the wide portion, and the narrow portion is formed. A coil spring 51 that elastically presses the collar portion of the annular collar 47 is disposed on the outer periphery of the clamp screw 41, and urges the clamp breaker 40 in a direction away from the throw-away tip 20 via the annular collar 47. . Therefore, the pressing portion 43 of the clamp breaker 40 is set based on the difference between the biasing forces of the wave washer 49 and the coil spring 51. To adjust this pressing force,
It may be replaced with a brake washer 48 having a different thickness.

The throw-away tip 20 attached to the tool main body 31 is driven to rotate with respect to the rotation of the workpiece W at a position where the workpiece W is cut and a desired cutting resistance is obtained. It is tilted at an appropriate angle.
(See Figure 4). In addition, as for the inclination of the throw-away tip 20, when the side rake angle α is less than −6 degrees, the rotational force for being driven by the rotation of the workpiece W is insufficient, and the side rake angle α is −40. If the degree is exceeded, the cutting resistance of the workpiece W increases, which hinders cutting. Therefore, it is necessary to set the angle within this range.

Since this embodiment is configured as described above, a steel workpiece W as shown in FIG. 5 is turned at high speed using the rotary tool according to this embodiment. Then,
Since the side rake angle is set to a negative value, the throwaway tip 20 is driven to rotate by the cutting resistance of the workpiece W, and during cutting of the workpiece W, the entire circumference of the throwaway tip 20 is substantially reduced. Work piece W evenly
And the wear also progresses uniformly over the entire circumference. As a result, the continuous processing time is extended.

Here, when the rotation axis of the throw-away tip 20 is set to the center axis of the tip body 22, it is necessary to manufacture the tip body 22 so that the coaxiality between the center axis of the tip body 22 and the outer peripheral surface is highly accurate. Is extremely difficult, and the finished surface roughness decreases during cutting. In that regard, according to the present embodiment, in the throw-away tip 20, the through-hole 2
If a high precision is obtained from the drilling position of No. 1 and the roundness of the outer peripheral surface of the shaft body 23, a high coaxiality can be obtained relatively easily (the drilling is more accurate than other processing methods). Easy).

As shown in FIG. 3, a rotary bite 30
The vertical shaft holes 39 and 42 and the shaft 2
If a high degree of accuracy is obtained with the roundness of the small diameter portions 25 of 3, the high coaxiality can be obtained relatively easily. Therefore, the finished surface roughness becomes highly accurate.

Since the throw-away tip 20 is elastically pressed by the pressing portion 43 of the brake collar 45, the throw-away tip 20 is caused by cutting resistance.
The driven rotation of is suppressed so as not to become faster than necessary. The driven rotation speed of the throw-away tip 20 can be appropriately adjusted by the wave washer 49. In this case, the pressing force of the throw-away tip 20 by the pressing portion 43 may be adjusted by adjusting the tightening force of the clamp screw 41 to increase or decrease the elastic force of the wave washer 49.

Further, the seat portion 38 has the concave portion 36.
Since the inner wall of the lower shaft hole 39 in contact with the shaft body 23 is abraded due to the cutting resistance acting on the throw-away tip 20, when the wall surface of a part of the lower shaft hole 39 is worn, the seat part 38 in the concave portion 36 is worn. The rotation and cutting accuracy of the throw-away tip 20 can be maintained by rotating the cutting resistance by changing the bearing position of the cutting resistance.

As described above, according to the throw-away tip 20 of this embodiment, the coaxiality of the central axis of rotation with respect to the tip body 22 can be easily improved, so that turning of steel or the like can be performed at high speed. Even in this case, the throw-away tip 20 is driven to rotate by the cutting resistance, so that local wear is reduced, the continuous machining time of the tip 20 can be significantly extended, and high machining accuracy can be obtained. In particular, in the case of the present embodiment, the rotation of the tip 20 is guided by being sandwiched by the seat portion 38 and the clamp breaker 40, but the coaxiality of the small diameter portion 25 of the shaft body 23 and the large diameter portion 24.
Since high accuracy can be obtained with respect to the concentricity of the outer peripheral surface, the outer peripheral surface is less shaken when the outer peripheral surface chip 20 is rotated, and as a result, the finished surface roughness of the workpiece is cut with the same chip fixed. The same thing as the case of doing is obtained.

Further, the diameter of the through hole 21 of the throw-away tip 20 is standardized, but the diameter of the shaft body 23 can be freely set to the small diameter portion 25 with respect to the large diameter portion 24. The throw-away tip 20 can be rotatably supported by the turning shaft having an ideal diameter regardless of the diameter of the through hole 21, and the ideal throw-away tip 20 can be easily rotated.

Another embodiment of the rotary bite of the present invention will be described below with reference to FIG. Reference numeral 60 in the drawing denotes a rotary bite of this embodiment. This rotary bite 6
Reference numeral 0 denotes a part of the configuration of the rotary bite 30 shown in FIGS. 1 to 5, in which an axis-free throw away tip 61 formed in a substantially disc shape and the throw away tip 61 are rotated. Tool body 6 that holds it freely
It consists of 2. The throw-away tip 61
Are two surfaces 63, 6 which have a circular outline in plan view and are opposed to each other.
4 are parallel to each other, a through hole 65 is formed so as to pass on the central axis thereof, and a ridgeline of at least one of the peripheral surface and the upper and lower surfaces 63, 64 is formed into a disc shape having a cutting blade 66. There is.

The tool main body 62 has a tip mounting portion 67 (corresponding to the sheet member 38 shown in FIG. 2) on which the throw-away tip 61 is mounted with its lower surface 64 abutting.
The throw-away tip 61 placed on the tip rest part 67 cooperates with the tip rest part 67 to provide an upper surface 63 thereof.
And a clamp member 68 that is clamped from the side. The tip mounting portion 67 and the clamp member 68 both project into the through hole 65 of the throw-away tip 61 and the rotation axis of the throw-away tip 61. Shaft 69, 69
Are formed. When the throw-away tip 61 is attached to the tool body 62, the throw-away tip 61 is tilted at an appropriate angle such that the throw-away tip 61 is driven to rotate with respect to the rotation of the workpiece W and a desired cutting resistance is obtained. The tilt angle of the throw-away tip 61 also needs to be set in the same range as that of the throw-away tip 20 described in FIGS. 1 to 5.

According to the rotary bite 60 of this embodiment, the shaft portion 6 is provided in the through hole 65 of the throw-away tip 61.
When the throw-away tip 61 is brought into contact with the workpiece W that rotates at a high speed in a state in which 9 and 69 are fitted and clamped from above and below, the workpiece W can be rotated with the shaft portions 69 and 69 as rotation axes. The throw-away tip 61 is driven to rotate and cuts the workpiece W. Therefore, according to the rotary bite 60, the throw-away tip 61 can be pivotally supported only by inserting the shaft portions 69, 69 into the through-hole 65 formed by the drilling process. Since the structure is simpler than that of the rotary bite described above, and it is not necessary to separately form a member serving as a rotary shaft, it is possible to provide a rotary bite having high coaxiality at low cost.

The throw-away tip 20 does not necessarily have to be formed in a cylindrical shape as in the present embodiment. For example, the peripheral side surface may be tapered. Furthermore, the throw-away tip 2 shown in FIGS.
The shaft body 23 of 0 may project only to one side of the throw-away tip 20, and the shaft portions 69, 69 of the rotary cutting tool 60 shown in FIG. 6 may be either the tip mounting portion 67 or the clamp member 68. It may be provided on only one side.

[0033]

According to the throw-away tip for a rotary bite according to the first aspect of the present invention, a shaft body formed with high roundness is inserted into a through hole of high coaxiality formed in the tip body. Therefore, the roundness of the whole is improved.

In the throw-away tip for rotary bite according to the second aspect, since the shaft portion of the throw-away tip for rotary bite projects on both upper and lower surfaces,
A high degree of coaxiality can be reliably ensured.

In the rotary bite according to the third aspect, since the indexable insert for the rotary bite having a high coaxiality is used, the machining accuracy of cutting is improved.

In the rotary bite according to the fourth aspect, the throw-away tip can be pivotally held with a high degree of coaxiality only by projecting the shaft portion of the tip mounting portion or the clamp member into the through hole provided in the throw-away tip. So
A rotary bite with high cutting accuracy can be provided at low cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing a throw-away tip for a rotary bite of the present invention.

FIG. 2 is a perspective view of a main part showing an embodiment of a rotary bite of the present invention.

FIG. 3 is a vertical sectional view showing the rotary bite of FIG. 2 and a throw-away tip mounted on the rotary bite.

FIG. 4 is a perspective view of a rotary bite and a throw-away tip mounted on the rotary bite according to an embodiment of the present invention, as viewed from a direction different from FIG.

FIG. 5 is a perspective view showing a relationship between a rotary bite according to an embodiment, a throw-away tip attached to the rotary bite, and a body to be cut.

FIG. 6 is a vertical sectional view showing another embodiment of the rotary bite of the present invention.

FIG. 7 is a plan view showing a conventional throw-away tip.

8 is a vertical cross-sectional view showing the throw-away tip of FIG.

[Explanation of symbols]

 20 throw-away tip 20a upper surface 20b lower surface 20c outer peripheral surface 21 through hole 22 tip body 23 shaft body 30 rotary bite 31 tool body 60 rotary bite 61 throwaway tip 62 tool body 63 upper surface 64 lower surface 65 through hole 66 cutting edge 67 chip placement Part 68 Clamp member 69 Shaft W Object to be cut

Claims (4)

[Claims] 1. A disc-shaped disc having a ridge line on at least one of the peripheral surface and the upper and lower surfaces thereof serving as a cutting edge, and the cutting edge is brought into contact with a rotating workpiece to be cut. In a throw-away insert for a rotary bite that rotates while being driven by a cutting body and cuts the body to be cut, two facing surfaces having circular circular contours in plan view and parallel to each other pass through the center axis of the cutting tool. And a disk-shaped chip body having a through hole formed therein, and a shaft fixed to the through hole of the chip body by press-fitting so that an end thereof projects from at least one of the upper and lower surfaces of the chip body. Throw-away tip for rotary bite, which has a body. 2. The throw-away tip for a rotary bite according to claim 1, wherein both ends of the shaft body project from the upper and lower surfaces of the tip body, respectively. . 3. The throw-away tip for a rotary bite according to claim 1, and a tool body to which the throw-away tip is attached, wherein the throw-away tip is centered on the shaft body. A rotary bite that is rotatably attached to. 4. A throw-away tip for a rotary bite and a tool main body to which the throw-away tip is attached, wherein the throw-away tip has a circular outline in a plan view and two opposing surfaces are parallel to each other. A through hole is formed so as to pass along the central axis, and at least one of the peripheral surface and the upper and lower surfaces is formed into a disc shape with a cutting edge, and the tool body contacts the lower surface with the throw-away tip. Any one of a chip mounting part that is placed in contact with each other and a clamp member that clamps the throw-away chip mounted on the chip mounting part from the upper surface side in cooperation with the chip mounting part, or A rotary bite that is formed on both sides with a shaft portion protruding from a through hole of the throw-away tip and serving as a rotation axis of the throw-away tip.