JPH0739524Y2 - Drill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a drill used for drilling holes.

[Prior Art] Usually, flat surface portions that are parallel to each other from the blade edge along the longitudinal direction are formed at opposite front and back positions on the outer surface of the blade portion, and a chip discharge groove having a V-shaped cross section is also formed between the flat surface portions. Drilling may be performed at a particularly high speed with a drill cut along the longitudinal direction from the blade edge.

[Problems to be solved by the device] However, it is difficult for this type of drill to be repelled due to its structure during rotation and it is difficult to sufficiently lubricate the cutting edge, and as a result, the lubrication effect is weakened and cutting friction heat is reduced. Generate
The welding phenomenon occurred at the cutting edge, and the required dimensional accuracy could not be secured along with the surface roughness of the inner peripheral surface of the machined hole. Further, there are various problems such that the service life of the drill itself is significantly reduced.

[Means for Solving the Problems] Therefore, the present invention solves such a problem,
Flat surface portions that are parallel to each other along the longitudinal direction from the blade edge are formed at opposite front and back positions on the outer surface of the blade portion, and a chip discharging groove having a V-shaped cross section is also provided between the flat surface portions along the longitudinal direction from the blade edge. In an engraved drill, a plurality of spiral cutting oil feeding grooves are provided on the surface of the flat surface portion over an appropriate length from the cutting edge to the cutting edge direction with respect to the rotation direction of the drill, and cutting is performed by each cutting oil feeding groove. It is configured so that oil is always forced out to the cutting edge side.

[Operation] In the drill of the present invention configured as described above, the supplied cutting oil enters the gap between the flat surface portion of the blade portion and the processing hole, and is directed toward the cutting edge by the cutting oil feeding groove provided on the surface of the flat surface portion. It is delivered with sufficient amount and pressure. As a result, the cutting edge is sufficiently cooled and lubricated, the welding phenomenon does not occur at the cutting edge, and the surface roughness of the machined hole and the dimensional accuracy can be secured. Furthermore, the precision and life of the drill can be maintained for a long time.

[Embodiment] An embodiment of the drill of the present invention will be described below with reference to the drawings. The drill of the present invention comprises a blade portion 2 having a cutting edge 1 at the cutting edge, a body portion 3 having a diameter larger than that of the blade portion 2, and a shank portion 4 for mounting and fixing to a machine tool or the like (not shown). Part 2
Has flat surface portions 5 and 5 which are parallel to each other along the longitudinal direction from the cutting edge at opposite front and back positions of the outer surface, and the outer peripheral surface of the body portion 3 is provided with a plurality of cemented carbide longitudinal members at equal intervals along the longitudinal direction. Material
The surfaces 6, 6, ... Are attached so that the surfaces thereof slightly project from the outer surface of the body portion 3. The cemented carbide longitudinal member 6 is for use as a guide. Further, the flat surface portions 5, 5 of the blade portion 2
Chip discharge grooves 7,7 having a V-shaped cross section extending from the cutting edge to the substantially intermediate position of the body portion 3 are engraved in between, and a shallow V is formed between the respective superhard longitudinal members 6,6 of the body portion 3. The oil passages 8, 8 ... Of the mold are engraved along the longitudinal direction.

Thus, a plurality of spiral cutting oil feeding grooves 9 are provided on the surfaces of the both flat surface portions 5 and 5 for a suitable length from the cutting edge to the cutting edge direction with respect to the rotation direction of the drill. Each cutting oil feeding groove 9,
As shown in FIG. 4, 9 ... is formed so that it is deepest at the position farthest from the cutting edge and becomes gradually shallower as it approaches the cutting edge.
As a result, the cutting oil can always be forced out toward the cutting edge. The deeper each of the cutting oil feeding grooves is, the greater the oil feeding effect is.

In the drill of the present invention thus constructed, the shank portion 4 is used by being supported and fixed to various machine tools or the like. Then, while the cutting oil is being supplied from the oil passage groove 8, the workpiece is perforated. At this time, even if the drill rotates at high speed, the cutting oil enters from the oil passage 8 into the gap between the blade portion 2 and the machining hole, where the flat surface portion 5,
The cutting oil feeding grooves 9, 9 provided in 5 sequentially forcibly extrude to the cutting edge side and supply the cutting edge 1. As a result, good cutting is always performed and the cutting edge 1 is cooled to prevent wear.
Perform stable drilling. In this way, even when drilling at a high speed, the cutting oil is fed toward the cutting edge with a sufficient amount and pressure, so that no welding phenomenon occurs. Also, the same effect can be obtained when the drill is fixed and the work is rotated to perform the hole drilling.

[Effects of the Invention] As described above, the drill of the present invention can send the cutting oil to the cutting edge with a sufficient amount and pressure even if it is rotated at a high speed by the cutting oil feeding groove provided in the cutting edge. The cooling and lubrication of the cutting edge can be performed without any problems, the welding phenomenon does not occur, the surface roughness of the drilled hole and the required dimensional accuracy can be secured, stable drilling can be performed, and pulling and working It is possible to facilitate and improve production. Moreover, it has a beneficial effect that the precision and life of the drill can be maintained for a long period of time.

[Brief description of drawings]

1 is a perspective view of a drill, FIG. 2 is a plan view of a blade portion, and FIG. 3 is a plan view of a blade portion with an angle of 90 ° different from each other. , Fig. 4 is X in Fig. 2.
It is an X-ray enlarged sectional view. 2 ... Blade part, 5,5 ... Flat surface part, 7,7 ... Chip discharging groove, 9
...... Cutting oil feed groove.

Claims (1)

[Scope of utility model registration request] 1. A flat surface portion which is parallel to a longitudinal direction from a blade tip is formed at front and back positions of the outer surface of the blade portion which face each other,
In a drill in which a chip discharge groove having a V-shaped cross section is similarly engraved between the flat surface portions along the longitudinal direction from the cutting edge, the flat surface portion has an appropriate length from the cutting edge to the cutting edge direction with respect to the rotation direction of the drill. A drill characterized in that a plurality of advancing spiral cutting oil feeding grooves are provided, and the cutting oil is always forcibly fed to the cutting edge side by the cutting oil feeding grooves.