JPH0985709A - Router bit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate burrs on the surface of a working material by rotating the outer peripheral cutting blade in the direction for retaining the material. SOLUTION: A router bit 1 is mounted at the spindle of a working head via a shank 2, and the bit 1 is rotated in the arrow direction by the spindle. The upper surface of the material 10 is cut to form a groove or a recess 11. In this case, since outer peripheral cutting edges 4a formed on a twisted shaft 3 cut while pressing the material 10 downward, even if the decorative sheet 10a of resin is fixed to the surface of the material 10, no burrs are raised at the upper edge 10b, but the material is cut. The chips produced by the peripheral cutting edges 4a, and bottom cutting edges 4b are guided upward along twisted grooves 5 by high-pressure air discharged from the discharge ports 6a of small holes 6 and smoothly externally discharged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wooden plate, a blade for forming a groove or a recess on a decorative plate having a resin decorative sheet adhered to the surface thereof, that is, a router bit.

[0002]

2. Description of the Related Art As a conventional technique, a columnar shank portion is formed on an upper portion of a main body, and a twisted shaft portion composed of a twisted side and a twisted groove having a function of feeding upwardly when the main body is rotated forward is formed. However, there has been a router bit in which an outer peripheral cutting edge is formed on the forward rotation side of the twisted side and a bottom surface cutting edge extending in the radial direction is formed at the lower end of the twisted shaft portion.

[0003]

In the above-mentioned prior art, since the outer peripheral cutting edge rotates in the biting direction to cut the work material, the outer peripheral cutting edge lifts and cuts the work material. There was a defect that burrs and chips were generated on the surface of the processed material. It is an object of the present invention to obtain a new router bit in which burrs do not occur on the surface of a processed material by rotating an outer peripheral cutting edge in a direction to press the processed material.

[0004]

The present invention is configured as follows in order to achieve the above object. That is,
In a router bit having a shank part on the upper part of the main body and a twisting shaft part on the lower part, the twisting shaft part is composed of a twist side having a feed function downward when the main body rotates forward and a twist groove, and An outer peripheral cutting edge is formed on the forward rotation side, a bottom surface cutting edge extending in the radial direction is formed at the lower end of the torsion shaft, and a small hole is provided in the axial center of the main body, and the lower end of the small hole is the lower end of the torsion shaft. It is configured to be opened from the outside.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, FIG. 1 is a side view showing an embodiment of the present invention, FIG. 2 is an II-II enlarged sectional view thereof, and FIG. 3 is an enlarged bottom view of FIG. In FIG. 1, reference numeral 1 is a router bit made of cemented carbide, which has a columnar shank portion 2 on an upper portion of a columnar main body and a torsion shaft 3 integrally on a lower portion (tip) thereof.
The diameter of the twisted shaft 3 is, for example, 16 mm, and the twisted shaft 3 has two twisted sides 4 and 4 and twisted grooves 5 and 5.
The twisted sides 4 and 4 and the twisted grooves 5 and 5 are twisted in a direction having a feeding function downward when the main body is normally rotated (arrow A).

Forward rotation of each of the twisted sides 4 and 4 (arrow A)
The outer peripheral cutting edges 4a, 4a are formed on the side, and each spiral side 4,
Bottom cutting edges 4b, 4b extending in the radial direction are formed at the lower end of 4. These peripheral cutting edges 4a, 4a, bottom cutting edges 4b, 4b
The rake angle and clearance angle are about 20 degrees. The rake angle and the clearance angle are appropriately set according to the material of the wood (working material), the cutting speed, and the like. Further, a small hole 6 is formed so as to penetrate the main shaft center portion, that is, the shaft center portion of the shank portion 2 and the torsion shaft 3. The small hole 6 has a shank portion 2 at the upper end.
Is opened to the outside from the upper end and the lower end is bifurcated, and the discharge ports 6a and 6a of the branched part are opened to the outside from the lower ends of the twisted sides 4 and 4.

Router bit 1 formed as described above
Is attached to a spindle (not shown) of the processing head via the shank portion 2, and the router bit 1 is rotated in the direction of arrow (a) in FIG. 1 by the spindle, and as shown in FIG. The upper surface is cut to form a groove or recess 11. In this case, since the outer peripheral cutting edges 4a, 4a formed on the torsion shaft 3 cut while pressing the processed material 10 downward, the decorative sheet 10a made of resin is fixed to the surface of the processed material 10. However, the upper edge portion 10b is cut without causing burrs. Further, the outer peripheral cutting edges 4a, 4a and the bottom surface cutting edge 4 described above.
The chips generated by the cutting of b and 4b are guided upward along the twist grooves 5 and 5 by the high pressure air discharged from the discharge ports 6a and 6a of the small holes 6 and smoothly discharged to the outside.

[0008]

As is apparent from the above description, according to the present invention, since the outer peripheral cutting edge is formed on the twisted side having a feeding function downward during rotation, burrs do not occur on the processed material. In addition, chips generated during cutting can be ejected as high pressure air from a small hole formed in the center of the main body and can be smoothly discharged to the outside through the twist groove.
Therefore, the present invention has an effect that a high quality processed product can be obtained.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along line II-II of FIG.

FIG. 3 is an enlarged bottom view of FIG. 1;

FIG. 4 is a cross-sectional view of essential parts showing a processed state.

[Explanation of symbols]

 1 Router Bit 2 Shank Part 3 Twisting Shaft 4 Twisting Edge 4a Peripheral Cutting Edge 4b Bottom Cutting Edge 5 Twisted Groove 6 Small Hole 6a Discharge Port 10 Work Material 10a Decorative Sheet 10b Top Edge 11 Recess

Claims (1)

[Claims] 1. A router bit having a shank portion at an upper portion of a main body and a twisted shaft portion at a lower portion, wherein the twisted shaft portion includes a twisted side having a feeding function downwardly when the main body rotates in a forward direction, and a twist groove. An outer peripheral cutting edge is formed on the forward rotation side of the twisted side, a bottom surface cutting edge extending in the radial direction is formed at the lower end of the twisting shaft portion, and a small hole is provided in the axial center of the main body, and the lower end of the small hole is formed. The router bit is characterized in that the twist shaft is opened from the lower end to the outside.