JP2507853Y2 - Cutting tool with circular slot insert - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a cutting tool capable of stably supporting a circular throw-away insert made of ceramics.

[Conventional technology]

Since ceramics have lower strength than cemented carbide,
A cutting tool that utilizes this often uses a circular throw-away tip that disperses the cutting load and covers the cutting edge.

However, the circular throw-away tip has a drawback in that it is difficult to firmly hold it because the side surface has an arcuate shape, and the rigidity of the entire cutting tool is difficult to obtain.

Therefore, as shown in FIG. 6, a supporting structure has been considered in which a convex portion 12 is provided on the bottom surface of the chip 11 and is inserted into the concave portion of the chip supporting sheet of the bite holder.

Further, as shown in FIG. 7, a V-shaped convex portion 22 is provided on the bottom of the chip 21, and a V groove for fitting the convex portion is provided on the chip support sheet to clamp the upper surface of the chip with a presser foot. The structure is also often used.

Further, as seen in Japanese Utility Model Laid-Open No. 64-26102, there is a device in which the bottom of a circular throw-away tip has a pyramid shape with three or more sides and the tip support sheet is a recess that fits into this.

[Problems to be solved by the device]

Ceramic chips, which have low strength, often cannot withstand the load and are damaged when moved during cutting. However, the support structure using the throw-away tip of FIG. 6 is not effective in increasing the restraining force because the projection 12 is loosely fitted into the recess of the support sheet. Further, if the fitting is made tight to compensate for the defect, breakage at the location of the convex portion 12 is likely to occur.

On the other hand, in the case of using the chip of FIG. 7, the restraint force against lateral deviation is increased, but as shown in FIG.
Since the V groove 23 provided at the position is perpendicular to the clamping force B, and the movement of the groove surface toward the front of the holder is not restricted, the cutting force causes the tip to stick out in front of the V groove. Moreover, the use corner of the chip is restricted to two corners, which causes an economic loss.

Further, in the supporting structure disclosed in Japanese Utility Model Laid-Open No. 64-26102, each surface of the pyramidal shaped portion of the chip having three or more surfaces is evenly adhered to the corresponding surface of the seat side concave portion, and at the same time, the arc-shaped chip side surface It is important to closely contact the side surface of the support seat, but since it is extremely difficult to process to meet this requirement, the chip actually rattles and the binding force is weak.

Further, as described above, ceramics are brittle in terms of strength, but the more the pyramidal part is in a multifaceted state, the more edges there are, and the higher the probability of loss.

Under these circumstances, the cutting tool using ceramics has a narrow application range and cutting conditions.

Therefore, there has been a demand for a cutting tool which has more restraining force and can stably clamp low-strength ceramics.

This invention seeks to meet that need.

[Means for solving the problem]

In order to solve the above-mentioned problems, this invention uses a slanted V-groove that makes the bottom surface of the chip support seat higher on the tip side of the holder and lowers toward the rear side, that is, the seat side surface side that receives the side surface (back surface) of the chip. The circular throw-away tip of which the lower portion has a three-sided pyramid shape has the inclined V groove to receive the two surfaces of the pyramid-shaped portion.

Although the inclined V-groove can be directly processed on the holder, it is advantageous to use a chip support sheet to process the inclined V-groove in consideration of workability and reproducibility of a damaged V-groove.

[Action]

When the top surface of the chip is pressed with a presser foot, the
The surface is pressed against each surface of the inclined V groove to restrain the lateral movement of the chip. Further, since the V groove is higher on the tip end side of the holder, the chip is also pressed against the slope of the V groove and the side surface of the chip support seat, and the reaction force generated at these pressing portions moves the rear part of the holder and the front part of the holder. Movement is also restricted.

In this way, the front surface, bottom surface, and back surface of the circular throw-away tip can be constrained by pressing the top surface, and the constraining force is further increased by applying the cutting force, enabling a strong and stable clamp. Become.

Further, since there are three surfaces of the pyramid-shaped portion, the usable corner of the chip is also three corners.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. 1 to 5.

The illustrated tool includes a tool holder 5 and a chip support sheet 4
With a circular throw-away tip 1 on the seat
Is placed. Therefore, the inclined V groove 7 is formed on the sheet 4.

The presser foot 3 is tightened with a bolt 2 to restrain the upper surface of the chip 1. The circular throw-away tip 1 has a pyramid-shaped bottom surface and a side surface 1d in which three surfaces 1a, 1b, and 1c having an equal inclination angle are evenly distributed, and two adjacent surfaces (1a and 1b in the figure). ) Are pressed against the two faces of the V-groove 7 separately.

The mounting direction of the chip 1 is such that when the chip 1 is placed on the chip supporting sheet of the bite holder 5, the surfaces 1a and 1b, 1b and 1
Any of the ridges created between c, 1c and 1a (1a and 1b shown)
It is determined that the ridgeline between them fits into the groove bottom of the V groove 7 and comes to the front in the holder longitudinal direction.

You can change the tip corner three times, and the supported surface changes to 1b and 1c, 1c and 1a. Therefore, the indexing of the chip corner is easy.

 The following is a description of the summary section.

As shown in FIG. 4, the V groove 7 has its position higher on the tip side of the holder and lower on the rear side, and the ridge line between the surfaces 1a and 1b of the chip fitted in this groove is also inclined in the same direction. are doing.

In this state, when the clamp force B due to the presser foot is applied to the upper surface of the chip 1, the chip 1 is pressed in the directions C and D of FIG. 4 and the directions E and E ′ of FIG. 5, and the surfaces 1a, 1b, 1c
A binding force due to a reaction force acts on.

Therefore, the movement of the tip is restricted in any of the front-rear direction and the left-right direction of the holder. When the cutting force A acts, the restraining force is further increased. Therefore, the tool rigidity at the time of cutting is extremely high, and even ceramic chips are not easily damaged.

Even if the same V groove is used, in the structure shown in FIG. 8, shifting to the front of the holder is inevitable, and if the mounting direction of the chip 1 is opposite to that shown in FIG. The direction of inclination of is also reversed, and the tip is rather easy to shift forward.

Further, if the pyramid portion below the chip has four or more surfaces, the contact area with the V groove is reduced, and it is difficult to obtain sufficient supporting force.

The chip used is not limited to the positive type shown. The same effect can be obtained with the negative type.

Further, the angle of V and the inclination angle of the V groove 7 affect the magnitude of the restraining force and the strength of the lower part of the chip, so it is necessary to select an appropriate angle in consideration of this point.

〔effect〕

As described above, according to the present invention, it is possible to firmly clamp a low-strength ceramic circular tip so that it will not move and be damaged even if an excessive cutting load is applied, and therefore, the application area of the ceramic tip. It is possible to greatly contribute to high efficiency machining by increasing the number of tools, improvement of cutting conditions, and longer tool life.

The present invention is also effective for a tool using a cemented carbide tip. That is, also in this case, the effects of stabilizing the cutting, improving the efficiency, and improving the processing accuracy by preventing the chip shift can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view showing an example of the cutting tool of the present invention, and FIG. 2 is a perspective view of a throw-away tip used.
FIG. 3 is a plan view of the chip mounted on the holder,
The figure is a sectional view taken along the line I-I of FIG. 3, and FIG. 5 is the same.
A sectional view taken along line II-II, FIGS. 6A and 6B are front views and bottom views showing an example of a conventional chip, and FIGS. 7A and 7B are front views and bottom views showing another example of a conventional chip, FIG. 8 is a side view showing a mounted state of the chip of FIG. 7, and FIG. 9 is a plan view showing an unusable case other than the present invention. 1 ... Circular throw-away tip, 2 ... Bolt, 3 ...
… Presser foot, 4 …… Chip support sheet, 5 …… Bite holder, 6 …… Side support seat side, 7 …… Inclined V groove, 1a,
1b, 1c ... Pyramid-shaped surface, 1d ... Side surface.

Continuation of the front page (72) Nobuhiro Takahashi 1-1-1 Kunyokita, Itami City, Hyogo Prefecture, Sumitomo Electric Industries, Ltd. Itami Works (56) Reference JP 49-88192 (JP, A) 64-26102 (JP, U) Shou 61-25923 (JP, Y2)

Claims (1)

(57) [Scope of utility model registration request] 1. A cutting tool in which a circular throw-away tip having a pyramid shape with a lower surface of three sides is received by a bottom surface and a side surface of a tip support seat, and the top surface is pressed to be attached to a holder. A cutting tool with a circular throw-away tip, characterized in that it is formed with an inclined V groove that is high on the tip side and descends toward the rear side, and the V groove receives the two surfaces of the pyramidal shaped portion.