JPS63216614A - Shoulder cutting milling cutter - Google Patents

Abstract

PURPOSE:To improve a cutting capacity by forming the rake angles in the axial and radial directions of a tip mounting seat face at 15 deg.-20 deg. and providing a clearance angle which is slightly larger than said rake angle on the cutting edge of a square truncated cone shaped tool tip. CONSTITUTION:A tip mounting seat face 5 which is formed into nearly a square shaped flat face is formed on the side facing a chip pocket 4 of the end part of each tip holding part 3. A relatively large rake angle beta is provided in the axial direction on each tip seat face 5 and its angle is in the range of 15 deg.-20 deg.. A tool tip 10 which is mounted on the tip mounting seat face 5 is of a throw away type and has a square truncated cone shape while its cutting edge is provided on the four sides of its bottom face side outer periphery. The inclination angle of an inclined side face which forms the flank of the cutting edge is slightly larger than that of the rake angle with respect to a center line. Accordingly, the chips produced by the square cutting edge can be made thick improving a cutting capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a milling cutter that performs shoulder milling, grooving, etc. using a peripheral cutting edge and a bottom edge, such as an end mill. Regarding the sharpening milling cutter.

Prior Art In a conventional shoulder milling cutter in which a plurality of tool tips are detachably attached to the circumference of a cutter body, the clearance angle of the cutting edge of the tool tip is relatively small, about 7 degrees. This is due to consideration of the rigidity of the tool tip.

Problems to be Solved by the Invention However, as mentioned above, if the clearance angle of the cutting edge of the tool tip is small, it is not possible to provide a sufficient rake angle on the cutting edge. There has been a problem in that the capacity is low and it cannot meet the high-speed cutting processes that have been required in recent years in machining.

The present invention was made in view of these circumstances, and at the same time increases the clearance angle provided on the cutting edge of the tool tip,
To provide a milling cutter having a high cutting ability capable of responding to high-speed cutting by increasing rake angles in the axial and radial directions provided on the tip mounting seat surface of the cutter body to which the tool tip is fixed. The purpose is to

According to the present invention, the tip mounting seat is a flat surface, and the rake angle in the axial and radial directions is approximately 15° to 15°.
The tool tip is formed at a relatively large angle of 20', while the tool tip has a truncated quadrangular pyramid shape, cutting edges are provided on the four sides of the outer periphery of the bottom side, and sloped side surfaces forming flanks of the cutting edge,
It is characterized in that it has an inclination angle with respect to the center line that is slightly larger than the rake angle in the axial and radial directions of the tip mounting seat surface, and a large relief angle is formed in the cutting edge.

Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings. 1 is a shank, 2 is a cutter body connected to one end of the shank 1, and three tip holding parts 3 extending in the radial direction are provided at angles of 120 degrees in the circumferential direction,
A large chip pocket 4 is formed between the chip holding parts 3, and a chip mounting seat surface 5 is formed on the tip end of each chip holding part 3 on the side facing the chip pocket 4.

The tip mounting seat surface 5 is formed into a substantially rectangular flat surface, and step portions 6 and 7 for supporting a tool tip 10, which will be described later, are provided at the lower and inner ends so as to be orthogonal to each other, and on the end surface side and the outer circumferential side. is open. Further, a mounting screw hole 8 is bored in the center of the chip mounting seat surface 5 .

As clearly shown in FIGS. 1 and 2, the chip mounting seat surface 5 is provided with rake angles of relatively large angles α and β in the axial and radial directions, respectively. The rake angles α and β are preferably in the range of about 15° to 20′, and in the illustrated embodiment, the rake angles α and β are both set at 17°. Such rake angles α and β
In order to facilitate the manufacturing process of the chip mounting seat surface 5 having
The rake angle β is designed based on the radius connecting the base point A and the center O of the shank 1.

The tool tip 1 is fixed to the tip mounting seat 5 mentioned above.
0 is a throw-away type, as shown in Figs. 5 and 6, the whole has a truncated square pyramid shape, each corner is chamfered 11, and a mounting hole 12 is drilled in the center. has been done. The cutting edge 13 is provided on the four sides of the outer periphery of the bottom side, and the inclined side surface 14 forming the flank surface of the cutting edge 13 has the rake angle α and β of the tip mounting seat surface 5 described above with respect to the center line.
The tool tip 10 shown in the drawings of the embodiment is designed to have an inclination angle θ=19°. Therefore, each cutting edge 13 has a large clearance angle of θ=19°. Note that the step portions 6 and 7 of the tip mounting seat surface 5 described above have inclined surfaces formed along the inclined side surfaces 14 of the tool tip 10.

The tool tip 10 described above is fixed at a predetermined position on the tip mounting seat 5 by screwing the screw 15 inserted into the mounting hole 12 into the screw hole 8 of the tip mounting seat 5.

As shown in FIGS. 2 and 3, the tool tip 10 fixed to the tip mounting seat 5 in this manner has 62 adjacent cutting edges 13a and 13b located outside the outer peripheral surface and end surface of the tip holding portion 3. An outer peripheral cutting edge 13a and a bottom edge 13b are formed to protrude slightly toward each other to process the workpiece. Both the outer peripheral cutting edge 13a and the bottom edge 13b formed in this way,
While it has a large rake angle of 17°, which corresponds to the rake angles α and β provided on the chip mounting seat surface 5, the difference between the clearance angle θ of the inclined side surface 14 and the rake angles α and β causes θ−α (or β) = 2° clearance angle. Therefore, the chips produced by the square cutting edges 13a and 13b are thick and have high cutting ability, and rough finishing such as shoulder cutting and groove processing can be performed extremely efficiently.

Further, the tool tip 10 is installed so that the entire part is inclined inward and toward the shank 1, and has an outer peripheral cutting edge 13a and a bottom edge 13b.
Since the inclination angle of the cutting edges 13a and 13b is larger toward the positive side, the chips from the cutting edges 13a and 13b are smoothly discharged to the shank 1 side through the chip pocket 4, and together with the large chip pocket 4, there is less heat generated by the chips. .

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, the rake angle in the axial and radial directions of the chip mounting seat provided on the cutter body is formed at a relatively large angle of about 15° to 20°, while Since each cutting edge of the truncated pyramid-shaped tool tip is provided with a relief angle that is slightly larger than the rake angle of the tip mounting seat,
The peripheral cutting edge and the bottom edge formed by the tool tip fixedly attached to the tip mounting seat have a large rake angle, and have good sharpness and high cutting ability, which has been demanded in recent years in machining. This has the effect of partially responding to the high efficiency of cutting processes.

The milling cutter according to the present invention is ideal for rough finishing such as shoulder milling and grooving.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a milling cutter according to the present invention, Fig. 2 is a plan view of a milling cutter according to the present invention;
The figure is a front view of the same, Figure 3 is an enlarged view taken along the line 3-3 in Figure 1, Figure 4 is a perspective view of the main body of the milling cutter, Figure 5 is a rear view of the tool tip, Figure 6 is a longitudinal sectional side view of the same. 1...Shank 2...Cutter body 3.
... Chip holding part 4 ... Chip pocket 5 ... Chip mounting seat surface 6, 7 ... Step portion 10 ... Tool tip 13 ... Cutting edge 13a ... Peripheral cutting edge 13b
...Bottom blade 14...Slanted side Patent applicant: Wa Seiki Co., Ltd., Figure 4, Figure J'. 1 roll) A 40 yesterday 2 14

Claims (2)

[Claims] (1) A cutter body fixed to one end of the shank,
A plurality of chip holding parts extending in the radial direction are provided at a certain angle in the circumferential direction, a chip pocket is formed between the chip holding parts, and a chip pocket is provided on the side of the chip holding part facing the chip pocket. A shoulder milling cutter in which a tool tip is removably fixed to a tip mounting seat, wherein the tip mounting seat is a flat surface, and rake angles α and β in the axial and radial directions are approximately 15° to 15°. The tool tip is formed at a relatively large angle of 20 degrees, and the tool tip has a truncated pyramid shape, cutting edges are provided on the four sides of the outer periphery of the bottom side, and the inclined side surfaces forming the flanks of the cutting edges are aligned with the center line. A shoulder milling cutter, characterized in that the cutting edge has an inclination angle θ slightly larger than the axial and radial rake angles α and β of the tip mounting seat, and a large relief angle is formed in the cutting edge. cutter. (2) The shoulder milling machine according to claim 1, wherein rake angles α and β in the axial direction and radial direction of the tip mounting seat are each 17 degrees, and the clearance angle θ of the tool tip is 19 degrees. cutter.