JP2000334603A - Machining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hold machining tools reliably in position for ultrasonic machining, in less time for machining tool changes. SOLUTION: This machining device has a tool holding part for gripping a tool 3 and transmitting ultrasonic vibration thereto, and machines a workpiece by placing the tool 3 into contact the rewith. The tool holding part has transmitting means 1 having an opening where the tool 3 can be partly inserted and transmitting ultrasonic vibration to the tool 3 thus inserted in the opening, and a holding member 2 pressing the tool 3 in the direction where it is inserted in the transmitting means 1, evenly via positions of the tool 3 practically symmetric about the axis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing apparatus for holding a tool used in an ultrasonic processing apparatus on a processing head of the apparatus.

[0002]

2. Description of the Related Art Conventionally, ultrasonic processing apparatuses have been used for cutting or grinding difficult-to-cut materials such as fine ceramics. As an example of a processing head of this ultrasonic processing apparatus, an ultrasonic vibrator that generates ultrasonic vibration, a processing tool is attached, and a horn that expands the amplitude of the generated vibration is provided. In an apparatus that performs processing by rotating, the processing head is provided with a rotating unit that rotates the ultrasonic vibrator and the horn.

[0003] Since processing tools of various diameters are used in this processing apparatus, small-diameter tools are mounted on a horn via a holding device. In addition, as a method, a processing tool is inserted into a hole where a slight gap is formed with respect to the outer diameter of the tool, and is fixed by bonding. The holding device to which the processing tool is joined is attached to the processing head using the screw hole of the horn. Thereafter, the machining tool is rotated, and the horn holder is adjusted so that the runout is eliminated, and the centering is performed.

[0004]

In the prior art as described above, since it is necessary to perform centering every time the processing tool is changed, there is a problem that it takes time to exchange the processing tool. In addition, if the joining is insufficient, not only is the ultrasonic vibration not well transmitted to the processing tool, but also the tool falls off during processing.

Accordingly, an object of the present invention is to provide a processing apparatus capable of performing ultrasonic processing while reliably holding a processing tool without requiring much time for changing the processing tool.

[0006]

According to the present invention, there is provided a tool holding portion for holding a tool and transmitting ultrasonic vibration to the tool, and contacting the tool with a workpiece. In a processing apparatus for processing a workpiece by making a tool, the tool holding portion has an opening through which a part of the tool can be inserted, and further includes a transmission unit that transmits ultrasonic vibration to the tool inserted into the opening, It has a holding member that presses down with a uniform force in a direction inserted into the transmission means at a position substantially symmetric with respect to the central axis.

As described above, when an opening is provided in a portion for transmitting ultrasonic waves to a tool, and a tool is inserted into the opening, the tool applies a force by the holding member so that a force is applied in the insertion direction. At this time, the tool is pressed with a substantially uniform force substantially symmetrically to the center axis of the tool. Further, according to the present invention, the bottom of the opening is provided with a protruding portion that comes into contact with one end of the inserted tool. If the protrusion is provided and comes into contact with one end of the tool as described above, the energy due to the ultrasonic vibration is easily transmitted to the tool, and the processing efficiency is improved.

Further, in the present invention, when the projected area of the cross section of the opening is D, the area of the projection is D / 2 or more. If the area of the projection is 1/2 or more of the area of the cross section of the opening, machining energy can be transmitted to the tool satisfactorily. Hereinafter, embodiments of the present invention will be described, but the present invention is not limited thereto.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an ultrasonic machining apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG.
1 is a schematic configuration diagram of an ultrasonic processing apparatus according to the present embodiment, and FIG. 2 is an enlarged cross-sectional view near a tool of the ultrasonic processing apparatus according to the present embodiment. By the way, the ultrasonic processing apparatus according to the present embodiment has the following configuration. The ultrasonic processing apparatus according to the present embodiment includes a base 12, a moving table 11 provided on the base 12 to move the work 10 in an arbitrary direction, and a column 9 fixed to the base 12. A machining head 8 provided with an ultrasonic vibrator for applying ultrasonic vibration to the tool 3 and an elevating means for moving the tool 3 close to or away from the workpiece 10, and a tool attached to the machining head 8. A rotating means 5 for rotating the horn 3, a horn 4 for expanding the vibration transmitted from the ultrasonic vibrator, and an opening formed in the horn 4 for inserting the tool 3, and the tool 3 is enlarged by the horn 4. It comprises a transmission means 1 for transmitting vibration and a nut 2 for holding a tool 3 inserted in the transmission means 1. In addition, the control of the moving table 11, the rotating means 5, the elevating means, the ultrasonic vibrator, and the like is performed by controlling means (not shown) such as movement control and operation control.

In the ultrasonic machining apparatus having such a configuration, the work 10 is set on the moving table 11 and the moving table 11 is driven until the tool 3 is positioned above the position where the work 10 is to be machined. Next, the ultrasonic vibrator is driven to generate ultrasonic vibration, the vibration is expanded by the horn 4, and the ultrasonic vibration is excited by the tool 3 inserted into the transmission means 1. Then, the lifting / lowering means is driven so that the tip of the tool 3 approaches the work 10 and machining is performed.

Since the ultrasonic machining apparatus according to the present embodiment is provided with the rotating means 5, it is possible to perform machining while approaching the workpiece 10 while rotating the tool 3. In such an ultrasonic machining apparatus, in the present invention, the tool 3 is fixed to the transmission means 1 with a structure as shown in FIG. An opening 1c is formed in the center of the transmission means 1 and has a depth approximately equal to the size of the shank 3S of the tool 3. The diameter of the opening 1c is formed with a tolerance that can form an intermediate fit with respect to the outer diameter axis reference fit of the shank 3s. By selecting such a dimensional tolerance, the close contact between the transmission means 1 and the tool 3 is enhanced, so that ultrasonic vibration can be transmitted efficiently, and the misalignment due to replacement of the tool 3 can be reduced. . Further, in order to improve the adhesion between the shank 3s and the opening 1c, the opening 1c and the shank 3s are finished with high surface accuracy and shape accuracy.

A projection 1d is provided at the innermost part of the opening.
Are formed. The projection 1d is provided for effectively transmitting ultrasonic vibration by making surface contact with the end end face of the shank 3s. In order to surely transmit the ultrasonic vibration, it is better that the area of the surface contact is large. When the sectional area of the opening of the transmitting member is D, the area of the plane of the projection 1d is D / 2 or more. It is desirable.

A space wider than the diameter of the shank 3S is formed only on both sides of the protrusion 1d. By the way, this space is a space necessary for processing and polishing the entire surface of the projection 1d in contact with the shank 3S.
When the projection 1d is formed, the shape is actually formed by wire electric discharge machining and polished by a grindstone.

On the other hand, the transmission means 1 has external threads 1a and 1b formed at both ends as shown in FIG. Upper male screw 1
“a” is screwed with a female screw (not shown) formed on the horn 4 of the ultrasonic processing apparatus, and fixes the transmission means 1 to the horn 4. The lower male screw 1b is screwed with the female screw of the nut 2, and the transmission means 1
Is fixed to the tool 3. The helical direction of these screws is the direction in which the rotating means 5 rotates during processing, and is formed in such a direction that the screws are tightened.

When the tool 3 is fixed to the transmission means 1, the tool 3 is fixed while pressing the end end face of the shank 3 s of the tool 3 in the insertion direction of the tool 3 by the nut 2. Also,
The nut 2 can press the end end face of the shank 3s substantially symmetrically with respect to the center axis 3a of the tool 3,
The force can be pressed almost equally at any position. Therefore, even when the ultrasonic vibration is transmitted to the tool 3, the manner of vibration of the tool 3 can vibrate symmetrically with respect to the central axis 3a. Since the transmission of the ultrasonic vibration to the tool 3 is performed from the transmitting means 1 and the nut 2, any material can be used as the material for the ultrasonic vibration.
Metal materials are preferred, and steel is preferred in consideration of workability and rigidity.

Next, a method of centering the tool 3 will be described with reference to FIG. FIG. 3 is a diagram showing a state in which the tool 3 and the transmission means 1 are attached to the horn 4. By the way, when performing centering, first, the transmission means 1 is attached to the horn 4.
Attach. Then, instead of the tool 3, a centering tool is inserted into the transmission means 1 fixed to the horn 4 and tightened by the nut 2. Next, the centering tool is slowly rotated together with the horn 4 via the rotating means 5, and the deflection of the tip of the centering tool is observed. While observing the run-out of the centering tool tip, the position of the horn flange 6 is adjusted with respect to the rotating means 5 to minimize the run-out of the centering tool tip. This completes centering. Then, remove the centering tool, attach the tool 3,
Desired processing is performed on the work 10.

In the ultrasonic machining apparatus according to the present embodiment, as long as the shank dimensions of the tool 3 are the same, the tool 3
It is not necessary to remove the transmission means 1 from the horn 4 at the time of replacement, so that it is not necessary to perform centering each time. The vibration 7 transmitted from the ultrasonic vibrator (not shown) is expanded in amplitude by the horn 4, and has a resonance frequency of 20 KHz so that the amplitude becomes maximum at the position of the transmission means 1, the nut 2, and the tool 3 fixed to the tip of the horn 4. Designed with. Horn 4
Is fixed and held on the rotating means 5 by a flange 6 provided near the node where the amplitude becomes zero.

The ultrasonic machining apparatus according to the present invention is not limited to a vertical ultrasonic machining apparatus, but is effective in a machining apparatus that performs machining by rotating the tool 3 while applying ultrasonic vibration. Further, cutting can be performed by using a drill or an end mill for the tool 3, grinding can be performed by using a grindstone, and polishing can be performed by using a polisher, and the processing is not limited.

The moving stage 11 used in the present ultrasonic processing apparatus may have an arbitrary stage such as an XY biaxial moving table or a rotary table depending on the processing mode. Further, in the present embodiment, the transmitting means 1 has a form detachable from the horn 4, but the present invention is not limited to this, and the transmitting means 1 and the horn may be integrally formed.

[0020]

As described above, according to the present invention, ultrasonic machining can be performed while securely holding a machining tool.
This has the effect of reducing processing costs.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an ultrasonic processing apparatus according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the vicinity of a tool 3 of the ultrasonic machining apparatus according to the embodiment of the present invention.

FIG. 3 is a diagram showing a state in which a tool 3 and a transmission means 1 are attached to a horn 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Transmission means 1a ... Horn mounting screw 1b ... Nut mounting screw 1c ... Opening 2 ... Nut 3 ... Tool 3s ... Shank 3a ... Center of tool 3 Shaft 3b Diamond abrasive layer 4 Horn 5 Rotating means 6 Flange 7 Vibration (schematic diagram) 8 Processing head 9 Column 10 Work 11: Moving stage 12: Base

Claims (3)

[Claims] 1. A processing apparatus for holding a tool and transmitting a ultrasonic vibration to the tool, the tool holding section being configured to contact the tool with the workpiece to process the workpiece. The holding portion has an opening through which a part of the tool can be inserted, and further includes a transmission unit that transmits the ultrasonic vibration to the tool inserted into the opening, at a position substantially symmetric with respect to a center axis of the tool. And a holding member for holding down with a uniform force in a direction inserted into the transmission means. 2. The processing apparatus according to claim 1, wherein a bottom portion of the opening is provided with a protrusion that abuts one end of the tool. 3. The processing apparatus according to claim 2, wherein, when the projected area of the cross section of the opening is D, the area of the projection is D / 2 or more.