JPH0248176Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cutting tool, and particularly to an improvement in a cutting oil supply means.

Generally, when drilling a hole in a workpiece using a drill press, the life of the drill should be extended, and
In order to achieve a beautiful finished surface, cutting oil is jetted from a conduit and supplied to the contact area between the drill and the workpiece to cool and lubricate the cutting edge.

However, with this method of supplying cutting oil, when the cutting speed becomes high, chips cannot be discharged smoothly from the cutting area, which increases the wear of the cutting edge due to heat generation at the cutting edge of the drill, and the drill There is a problem that breakage accidents are more likely to occur, and breakage accidents are more likely to occur due to sticking of the drill and workpiece due to clogging of chips, and the life of the drill is shortened.

As a drill to solve this problem, a drill has been proposed in which a spout is provided on the cutting edge surface and cutting oil is supplied from the cutting edge surface.

However, in such drills, the spout is open on the cutting edge surface, so when the supply pressure of cutting oil decreases, the chips become clogged in the torsion groove, leading to the problem of drill breakage. .

An object of the present invention is to provide a cutting tool that can effectively discharge chips using cutting oil.

In order to achieve this objective, the present invention forms a passage in the main body of the cutting tool to supply cutting oil to the cutting edge surface, and also opens a small hole in the groove of the cutting tool so as to communicate with the passage to supply cutting oil. Chips that tend to clog the groove are discharged by ejecting them into the groove from the small hole through the passage.

The present invention will be described below with reference to embodiments shown in the drawings.

Fig. 1 is a side view showing a drill which is an embodiment of the present invention, Fig. 2 is a bottom view thereof, Fig. 3 is an enlarged sectional view taken along the line of Fig. 1, and Fig. 4 is Fig. 3 -
FIG. 3 is an enlarged cross-sectional view taken along the line.

In this embodiment, this drill has a main body 1 formed in a substantially cylindrical shape, and approximately half of one side of the main body 1 (hereinafter referred to as the base end side) has a part that allows the drill to be used as a chuck of a drilling machine, etc. A taper shank 2 for holding is formed. On the outer circumferential surface of the tip end of the main body 1, two spiral grooves 3 for automatically removing chips are arranged with a phase difference of about 180 degrees from each other and are spirally carved. .
A tip 4 molded from cemented carbide sintered alloy or the like is attached to the tip of the main body 1, and the tip 4 is formed with a predetermined cutting edge angle to perform cutting.

A passage 5 is bored approximately on the center line inside the main body 1, extending from the proximal end surface of the taper shank 2 to the distal end thereof. It is desirable to set the cross-sectional area of the passage 5 to as large a value as possible without impairing the essential functions of the drill, such as its mechanical strength.

A plurality of small holes 6 are bored in the twisted groove 3 of the main body 1 at approximately right angles to the tangents of the curved surfaces of the passage 5 and the twisted groove 3 so as to reach the passage 5 from the bottom of the twisted groove 3. The small holes 6 are arranged in a row within the helical groove 3 with substantially equal pitches. The cross-sectional area, number, arrangement, pitch, etc. of the small holes 6 are determined by the chip discharge function using cutting oil, which will be described later.
It is desirable that the settings be made so that the function of supplying cutting oil to the cutting edge, etc., is performed effectively, and the essential functions of the drill are not impaired.

Next, the action will be explained.

The drill according to the above configuration is attached to the chuck of a drilling machine or the like at its taper shank 2. In its installed state, the drill passageway 5 is fluidly connected by suitable means to a supply of cutting fluid (not shown).

When cutting is started by the tip 4 of the drill, the cutting oil pumped from the supply source to the passage 5 passes through the passage 5 and flows out from each small hole 6 into the helical groove 3. Chips generated during cutting are automatically transferred from the tip 4 into the helical groove 3 by rotation of the drill, whereby the chips are relatively removed from the tip 4. The chips relatively transferred into the helical groove 3 gradually move into the helical groove 3.
As a result, there is a possibility that a clogging phenomenon of chips may occur in the helical groove 3.

However, in this embodiment, since the cutting oil flows out from the group of small holes 6 into the helical groove 3, chips that are about to clog in the helical groove 3 are removed from the chips 4 by the flowing cutting oil. At the same time as being transferred from the inside of the helical groove 3, it is constantly discharged from the inside of the helical groove 3.
Therefore, the accumulation of chips in the helical groove 3 is prevented, and the occurrence of the phenomenon in which the helical groove 3 is clogged with chips is avoided.

The cutting oil flowing through the passage 5 and the group of small holes 6 cools the drill throughout.

According to this embodiment, since the cutting oil can flow out from the helical groove, the chips can be reliably discharged from the helical groove, thereby preventing the occurrence of drill breakage accidents due to chips clogging the helical groove. This can be prevented.

Furthermore, since cutting oil can be supplied to the cutting edge region through the helical groove, cooling and lubrication in the cutting region can be effectively performed. Therefore, cutting efficiency can be increased, a beautiful finished surface can be obtained, and the life of the cutting edge can be extended.

Moreover, as the cutting oil flows through the passages and small holes, the entire drill is cooled.
Cutting efficiency can be further improved.

Since cooling and lubrication can be performed effectively, the cutting feed rate can be set quickly, making it possible to shorten working time.

Since the fear of breakage accidents is eliminated and the lifespan of the tip and drill is extended, the time for replacing the drill can be extended, and productivity can be improved.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and may be modified without departing from the gist thereof.
It goes without saying that various changes can be made.

For example, the small holes are not limited to being perpendicular to the grooves and passages, but may be inclined forward or backward relative to the direction of rotation of the drill, or may be inclined toward the cutting edge.

The small holes are not limited to being arranged in one row in the groove, but may be arranged in two or more rows, and the position, pitch, diameter, etc. of the holes are not limited to being set regularly, but may be set irregularly. good.

There are no limitations on the form, cross-sectional shape, number of grooves, etc. in which the small hole groups are formed, and the grooves are not limited to a spiral shape, but may be linear, and are not limited to an arcuate cross section, but may also have a triangular cross section. , there may be two or more articles.

In the above embodiment, a drill with a tip has been described, but the present invention is not limited to this, but can be applied to a drill without a tip, and furthermore, to other cutting tools such as the blade of an end mill.

As described above, according to the present invention, it is possible to prevent chips from clogging the groove, and to effectively perform cooling and lubrication during cutting.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a drill which is an embodiment of the present invention, Fig. 2 is a bottom view thereof, Fig. 3 is an enlarged sectional view taken along the line of Fig. 1, and Fig. 4 is Fig. 3 -
FIG. 3 is an enlarged cross-sectional view taken along the line. 1... Main body, 2... Taper shank, 3... Twisted groove, 4... Chip, 5... Passage, 6... Small hole.

Claims (1)

[Scope of utility model registration request] A cutting tool having a twisted groove around the main body, wherein a passage is bored approximately on the center line inside the main body from the proximal end surface to the distal end of the main body, and a plurality of small holes are formed in the twisted groove along approximately the entire length of the cutting tool. The grooves are arranged at substantially equal pitches across the helical groove and are opened in the radial direction so as to reach the passage from the bottom surface of the helical groove, and the cutting oil is jetted from the small hole group into the groove through the passage. A cutting tool characterized in that it discharges chips that tend to get stuck in the groove.