JPH07285002A - Vibration control tool for depth machining - Google Patents

Abstract

PURPOSE:To provide a vibration control tool whose vibration control effect is not deteriorated even in long term use in a long vibration tool, in which a high rigidity material such as a carbide alloy is used in a part. of a tool main body so as to improve vibration control effect, for depth machining. CONSTITUTION:A round rod 7 having a taper part fitting for a taper hole 8 is inserted into the taper hole 8 perforated in a tool main body 2, and the round rod 7 is fastened from the rear end via a washer 11 by means of a push-on screw 10. The round rod 7 is pressedly fixed in the inside of the tool main body 2, and a pre-load is always loaded, so that vibration control effect in the initial stage can be maintained for a long time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration tool for deep machining, and provides an anti-vibration tool that maintains its anti-vibration effect even after long-term use.

[0002]

2. Description of the Related Art A boring tool is taken as an example of one of the most common vibration-proofing tools for deep machining. Also,
For high rigidity materials used as part of the tool body material,
There are various ceramics, WC-based special sintered alloys,
Hereinafter, the most widely used cemented carbide will be described as an example.

Since cemented carbide has a large Young's modulus and a high rigidity, it has hitherto been used not only as a cutting edge tip but also as a main body material for a long cutting tool such as a boring tool to prevent chatter vibration. It has the effect of improving processing accuracy. The best known example is a boring tool 1 shown in FIG. 4, in which a tool body 2 made of cemented carbide and a head 3 made of steel are joined by brazing 4. The head 3 is provided with a tip seat, and the cutting edge tip 5 is mounted and fixed by a tightening screw 6 of a countersunk screw.

However, the boring tool 1 as described above,
Damage from the brazed joint 4 due to overcutting or damage due to softening of the brazing layer due to cutting heat may occur. On the other hand, since a high-rigidity material such as cemented carbide is liable to be brittle and broken, it may be broken due to a slight mishandling such as impact.

The boring tool 1 shown in FIG. 5 has been put into practical use as a means for solving the above problems. A straight bar 7 made of cemented carbide is used as a tool body 2.
It is integrated by being press-fitted into a hole drilled from the rear end. As a result, the problem caused by brazing is eliminated and the cemented carbide is not exposed to the outside, so the breakage problem is also alleviated.

[0006]

However, the boring tool as shown in FIG. 5 has a problem that the steel material and the cemented carbide are brought into close contact with each other due to the influence of vibration during cutting, the deformation of the tool body made of steel material and the change over time. The strength was slackened, and the anti-vibration effect tended to deteriorate with use.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and in order to provide an antivibration tool which does not deteriorate in antivibration effect even after long-term use, the following is provided. Such means is used.

That is, in an anti-vibration tool for deep machining, in which a high rigidity material such as cemented carbide is used for the purpose of enhancing the anti-vibration effect in a part of a long tool body, the axial center of the tool body is used. A hole having a tapered portion with a diameter on the base side larger than a diameter on the tip side is bored from the rear end. Next, a round bar made of the high-rigidity material having a taper part that fits the taper part is inserted into the hole, and the round bar is screwed into a screw part screwed near the entrance of the hole. So that it is pressed and fixed in the tool body.

The round bar having a tapered portion made of a highly rigid material may have a shape in which the middle of the tapered portion has a diameter slightly smaller than both ends of the tapered portion.

[0010]

In the vibration isolating tool for deep machining according to the present invention, as described above, the problems of breakage due to brazing and breakage due to brittleness of a highly rigid material are unlikely to occur. Moreover, the steel material of the tool body and the high-rigidity material that serves as the core material are taper-fitted, and since the preload is constantly applied by the push-in screw in the longitudinal direction from the rear end, the taper fitting adhesion strength is Maintained for a long time. As a result, the anti-vibration effect is maintained forever.

Further, the thick taper shape of the base portion not only increases the bending rigidity but also increases the natural frequency, which has a favorable effect on the prevention of chatter vibration and the improvement of machining accuracy.

The small diameter portion provided in the middle of the tapered portion is
In consideration of manufacturing the anti-vibration tool of the present invention, when the contact area between the taper hole and the core material is insufficient or uneven, a slime is provided in the middle to provide both ends of the taper. The contact area of the part is increased.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the vibration damping tool for deep working of the present invention will be described with reference to the drawings.

FIG. 1 shows an example of application to a boring tool.
The boring tool 1 is composed of a tool body 2 and a head 3 made of steel. The head 3 is provided with a tip seat, and the cutting edge tip 5 is attached and fixed by a tightening screw 6 of a countersunk screw. A taper hole 8 is formed in the tool body 2 from the rear end along the major axis. In the present embodiment, the tapered hole 8 is a complete taper whose diameter gradually decreases toward the tip over the entire length of the hole, but depending on the tool shape, for example, a stepped shape with a straight portion at the tip may be used. It doesn't matter.

A round bar 7 of cemented carbide having a taper suitable for this is inserted into the tapered hole 8. A screw 9 is screwed in the vicinity of the entrance of the taper hole 8, and by tightening a push-in screw 10 that is screwed into the screw 9, the round bar 7 is always loaded with a preload in the distal direction of the long axis via a washer 11. It will be in the state of being.

In such a boring tool 1, since the taper fitting adherence is maintained for a long time, deterioration of the vibration damping effect due to aging is prevented.

FIG. 2 shows another embodiment according to claim 2,
The same parts are designated by the same reference numerals. The structure of the boring tool 1 in this figure is not different from that of FIG. 1, and only the shape of the round bar 7 is slightly different. That is, the round bar 7
This is an effective means in the case where it is difficult to manufacture the taper fitting so that the contact surface condition becomes uniform by making the diameter of the middle part slightly smaller than both ends.

Further, an example in which the present invention is carried out by a milling arbor for mounting a rolling tool will be described with reference to FIG.

The milling arbor 12 is composed of a tool body 2 which is an arbor and a taper shank 13 with a bottle grip. The tool body 2 and the taper shank 13 are initially manufactured individually.

A cylindrical projection 15 is provided at the center of the tip flat surface 14 of the tool body 2, and is adapted to be fitted into a milling hole of a cutting tool such as a shell end mill or a spot facing cutter. These cutting tools are fixed by tightening bolts screwed into a screw hole 16 formed at the center of the protrusion 15. The drive key 1 is the protrusion on the outer periphery of the tip flat surface 14.
7 is for fitting a key groove formed on the back surface of the cutting tool to transmit the rotational force.

The inside of the tool body 2 has the above-mentioned boring tool 1
It has the same structure as. That is, the taper round bar 7 made of cemented carbide is inserted into the taper hole 8 along the shaft center, and is fixed by pressure contact by tightening the push-in screw 10 via the washer 11.

After this, the tool body 2 is inserted into the hole 18 provided in the taper shank 13 and integrated. As the method of integral joining, a method by cold fitting or shrink fitting as shown in the figure, a method by adhesive or brazing, or a method by taper screw fitting is adopted.

[0023]

As described above, in the vibration isolating tool for deep machining of the present invention, the adhesion between the highly rigid material inserted as the core material for enhancing the vibration isolating effect and the inner surface of the hole changes with time. Since it is kept constant without being used, the anti-vibration effect is maintained even after long-term use.

[Brief description of drawings]

FIG. 1 is a front view including a partial cross section of a boring tool according to an embodiment of the present invention.

FIG. 2 is a front view including a partial cross section of a boring tool according to another embodiment of the present invention.

3A and 3B are a front view including a partial cross section and a left side view of a milling arbor that is another embodiment of the present invention.

FIG. 4 is a front view showing an example of a conventional boring tool.

FIG. 5 is a front view including a partial cross section showing another example of a conventional boring tool.

[Explanation of symbols]

 1 Drilling Bit 2 Tool Body 4 Brazing 5 Cutting Edge Tip 7 Round Bar 10 Pushing Screw 11 Washer 12 Milling Arbor

Claims (2)

[Claims] 1. A tool in which a cutting edge tip is attached to the tip of a long tool body so that a deep portion of a work material can be cut, and a vibration damping effect is provided on a part of the tool body. In an anti-vibration tool for deep machining using a high-rigidity material such as cemented carbide for the purpose of increasing, in the tool body, a taper portion whose base side diameter is larger than the tip side diameter is provided along its axis. Has a hole formed in the rear end thereof, and a round bar made of the high-rigidity material having a tapered portion matching the tapered portion is inserted into the hole and screwed into a screw portion screwed near the entrance of the hole. An anti-vibration tool for deep machining, characterized in that the round bar is press-fitted and fixed in the tool body by a matching push-in screw. 2. The round bar made of a high-rigidity material having the taper portion has a shape in which the middle of the taper portion is slightly smaller in diameter than both ends of the taper portion. An anti-vibration tool for deep machining according to item 1.