JPH0694082B2 - Ultrasonic vibration processing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic vibration machining apparatus for ultrasonically vibrating a cutting tool to perform machining operations such as turning and shaping.

2. Description of the Related Art In recent years, an apparatus has been developed that performs ultrasonic wave vibration on a cutting tool to perform machining operations such as cutting and grinding. This is one in which a cutting tool is connected to an ultrasonic vibrator having an electrostrictive element or the like and is ultrasonically vibrated in a tangential direction of a workpiece to improve processing accuracy. As such an apparatus, there is an apparatus disclosed in Japanese Patent Application No. 62-279637 proposed by the present applicant.

Therefore, the second conventional example of such an ultrasonic vibration machining device is
A description will be given with reference to FIGS. First. A cutting device 1 which is an ultrasonic vibration machining device includes a tip 2, a cutting tool 3 having the tip 2 fixed to a tip thereof, and a cutting tool 3
And a flexural vibrator 4 which is an ultrasonic vibrator connected to each other. Here, the flexural vibrator 4 includes an electrostrictive element 8, electrode plates 9 and 10, an electrostrictive element 11, and a common electrode plate between a bite supporting member 6 in which a bolt hole 5 is formed and a bolt 7.
12 and end material 13 are held in this order. As illustrated in FIG. 3, the electrode plates 9 and 10 are formed in a semi-circular shape with a terminal portion protruding, and as illustrated in FIG. 4, the electrostrictive elements 8 and 11 include the electrodes. Electrodes 14 to 17 which are electrically connected to the plates 9 and 10 are formed on the surface. A cylindrical insulating member 18 is inserted between the bolt 7 and the electrostrictive elements 8 and 11, the electrode plates 9 and 10. On the other hand, the front end portion of the cutting tool support member 6 is formed in a shaft-like shape so as to form a screw 19, and the cutting tool 3 having a reverse screw 20 formed at the end portion thereof has both screws.
Fasteners 22 formed with 21 are detachably connected.

In addition, conical holes 23 and 24 for fixing the cutting device 1 are formed on the side surfaces of the cutting tool support member 6 and the end member 13.

In such a configuration, the cutting device 1 applies a reverse-phase voltage of a predetermined frequency to the electrode plates 9 and 10 with the common electrode plate 12 as a reference, so that the bending as illustrated in FIG. The chip 2 vibrates resonatingly due to the vibration amplitude distribution. Therefore, by cutting the chip 2 into a workpiece (not shown) in such a state, precise cutting can be performed.

In the above cutting device 1, the tip 2 is fixed to the bite 3 by brazing or the like. However, in such a cutting device, a throw-away tip 25 as shown in FIG. 6 may be used. is there. This is a disposable tip that is replaceable with the tip 2 that is normally fixed to the cutting portion of the cutting tool 3, and is replaced when worn. Therefore,
As illustrated in FIG. 7, a mounting hole 26 that is a bolt insertion hole.
The throw-away tip 25 formed with is fixed to a special-purpose bite 27 having a screw hole (not shown) with a tip fixing bolt 28 for use in cutting work.

However, as illustrated in FIG. 7 (a), the throw-away tip 25 is connected to the bite 27 at the bottom, so that the center of gravity of the flexural vibration moves downward and the throw-away tip moves. Tip
The angle of vibration θ of the blade edge of 25 is greatly inclined.
In this case, in order to secure the rake angle of the cutting edge, bit 27
It is necessary to incline the surface on which the throw-away tip 25 of
The oscillating direction angle θ of the blade edge is further inclined.

The above-mentioned problems are, for example, TPGT0820 (JIS-B4120-
It does not occur when a small and lightweight throw-away tip such as 1985) is used, but it is remarkable when a large throw-away tip such as TPGT1102 is used to increase the cutting amount. .

Means for Solving the Problems A throw-away tip provided with a bolt insertion hole, a bite in which at least the tip fixing portion is made of a super hard material and a nut is fixed, and a bolt for inserting the throw-away tip into the nut of this bite. It consists of a tip fixing bolt screwed through a hole and an ultrasonic vibrator supporting the cutting tool.

Action Since at least the tip fixing part is made of cemented carbide, it is possible to increase the equivalent mass from the cutting edge of the throw-away tip to the first node, which allows the cutting edge to retain a large amount of energy. Work efficiency can be improved, and since the tip fixing part has high rigidity and mass, the amount of change in the vibration direction is small and processing accuracy is high. By doing so, it is not necessary to form a screw hole in the chip fixing portion formed of the superhard material, and thus the device can be easily manufactured.

Embodiment An embodiment of the present invention will be described with reference to FIG. The cutting device 29, which is the ultrasonic vibration machining device of the present embodiment, is formed for the throw-away tip 25 having the attachment hole 26 described above. Therefore, in this cutting device 29, on the lower surface of the base 30 in which R is formed at the front edge so as to increase the vibration amplitude,
For example, a chip fixing portion 31 formed of a high-density and high-rigidity material is integrally fixed by brazing or the like to form a cutting tool 32. A nut 33 with a flange is embedded in the round hole 34 and fixed to the chip fixing portion 31 of the cutting tool 32 by brazing or the like. Therefore, the throw-away tip 25 is the tip fixing part.
It is fixed to 31 by a chip fixing bolt 28 and a flanged nut 33. The structure of the bending oscillator 4 of the cutting device 29 is similar to that of the cutting device 1 described above.

With such a configuration, the cutting device 29 performs cutting work by ultrasonic vibration similarly to the cutting device 1 described above. Further, the throw-away tip 25 is fixed to the tip fixing portion 31 with the nut 33 with a flange and the tip fixing bolt 28 attached to the tip fixing portion 31 from below, which makes it very difficult to process the tip fixing portion 31. Since it is not necessary to form a special screw hole, the productivity of the device is high.

A superhard material is used as the high-density and high-rigidity material in which the chip fixing portion 31 is formed.

Here, the maximum cutting capacity by ultrasonic vibration of the cutting device 29 as described above is the equivalent mass m from the cutting edge to the first node N1.
And the vibration speed V. Therefore, when the energy having the cutting edge of the indexable insert 25 and E, the E = mV ^2/2. In other words, the cutting amount increases as the equivalent mass m and the vibration speed V increase, and when the cutting amount is the same, the energy stored is large and the change in the amplitude and direction of the vibration is small, thus improving the working accuracy. I understand.

The Applicant manufactured a cutting tool, which was integrally formed of stainless steel and had a chip fixing portion, as an experimental material of a conventional product. Therefore, throwaway tip TPGT110208 (JIS-B
4120-1985) was bolted at a mounting angle of 12 °, and the vibration of the cutting edge was measured. The resonance frequency was 19.5 (KHz) and the vibration direction angle θ was 25 °. Therefore, tilt the device 25 degrees,
When the cutting operation was performed with the vibration direction and the cutting direction aligned, the rake angle of the cutting was -13 ° and the cutting resistance was large and the cutting could not be performed well. The tip of the tip was ground to 18 ° and the cutting rake angle was set to + 5 °. SK material of φ40 (mm) is prepared as the object to be cut, and its rotation speed is 200 (rp
m), the cutting feed rate was 0.125 (mm / rev), and the cutting depth was gradually changed to measure the machining limit. The cut depth is 0.85 (mm) and the ultrasonic transducer input is 66 (W). When the cut depth is increased to 1.05 (mm), the ultrasonic transducer input rises to 105 (W). The tip of the tip is damaged.

Therefore, when observing the cutting surface of the work piece processed as described above, the state is different from the part where the single-sided cutting depth is 0.65 (mm), and the amplitude and direction of the vibration of the tip of the tip Was found to have changed. It is considered that this is because the equivalent mass from the cutting edge to the first node was small, so that the cutting edge was not able to retain a large amount of energy despite the large driving capacity of the ultrasonic transducer.

Next, as an experimental material of the present invention, the applicant of the present invention used a cutting tool having a structure as shown in FIG. 1 to braze a chip fixing part made of a super hard material with a base made of stainless steel via a copper foil. Then, it was manufactured by embedding a nut with a flange made of stainless steel (not shown). Therefore, when the same throw-away tip as the above experimental material was bolted at a mounting angle of 12 ° and the vibration of the cutting edge was measured, the resonance frequency was 19.5 (KHz).
At that time, the vibration direction angle θ was 8 ° and the vibration amplitude was 17 (μm). Therefore, when the cutting operation was performed by inclining the device to 8 ° without grinding the cutting edge, the rake angle of cutting was + 4 °.

Then, when an experiment was conducted under the same conditions as those of the above-mentioned cutting device, stable cutting could be performed and damage of the cutting edge did not occur even when the depth of cut of the single wall was 1.65 (mm). In addition, the ultrasonic transducer input at this time was 94 (W), indicating that the energy possessed by the cutting edge has a margin.

In addition, the above-described effects are similarly produced by a single-edged tool as well as the serious tool shown in the drawing. Further, in the cutting device 29 of the present embodiment, the tool 32 and the flexural vibrator 4 are fastened to each other with a fastener.
However, the present invention is not limited to this, and a tool in which a cutting tool and an ultrasonic vibrator are integrally formed, or a vibrating body driven by a vertical ultrasonic vibrator is used as a cutting tool. It is possible to use the one with the attached. Further, in the cutting device 29 of the present embodiment, the tip fixing portion 31 formed of a super hard material is attached to the base of the bite 32, but the present invention is not limited to this, and the entire high density is achieved. It is also possible to use a bite or the like (not shown) made of a highly rigid material.

Advantageous Effects of Invention The present invention, as described above, includes a throw-away tip having a bolt insertion hole, a bite in which at least the tip fixing portion is made of a cemented carbide material and a nut is fixed, and the throw-away nut is attached to the nut of the bite. Since it consists of a chip fixing bolt that is screwed in through the bite insertion hole of the chip and an ultrasonic vibrator that supports the bite, it is possible to increase the equivalent mass from the cutting edge of the throw-away chip to the first node. The blade tip can hold a large amount of energy to improve the efficiency of machining work. Moreover, the rigidity of the tip fixing part is high and the mass is large, so the amount of change in the vibration direction is small and It is highly accurate, and it is necessary to form a screw hole in the chip fixing part made of super hard material by fixing the nut to the chip fixing part. Therefore, there is an effect that the device can be easily manufactured.

[Brief description of drawings]

FIG. 1 is a vertical side view showing an embodiment of the present invention, FIG. 2 is a perspective view of an ultrasonic vibration machining device proposed in the past by the present applicant, FIG. 3 is a perspective view of an electrode plate, and FIG. Is a perspective view of the electrostrictive element, FIG. 5 is a vertical sectional side view showing the vibration amplitude distribution of the ultrasonic processing device, FIG. 6 (a) is a plan view of the throw-away tip, and FIG. 6 (b) is a side view. 7 (a) and 7 (b) are side views of the cutting tool. 4 ... Ultrasonic transducer, 25 ... Throw-away tip, 26
...... Bolt insertion hole, 28 ...... Chip fixing bolt, 29 …… Ultrasonic processing device, 31 …… Chip fixing part, 32 …… Bite, 33
……nut

Claims (1)

[Claims] 1. A throw-away tip having a bolt insertion hole, a bite in which at least the tip fixing portion is made of a super hard material and a nut is fixed, and a bolt insertion hole of the throw-away tip in the nut of this bite. An ultrasonic vibration machining device, comprising: a chip fixing bolt screwed through; and an ultrasonic vibrator supporting the cutting tool.