JPH0565311B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for machining a workpiece by also imparting vibration to a tool.

Conventionally, in the field of cutting and grinding workpieces, it is known that highly efficient machining can be achieved by applying superimposed vibrations of low frequency vibration and ultrasonic vibration to a tool.

The reason why such highly efficient machining is possible is that firstly, the addition of ultrasonic vibration reduces the back force compared to conventional cutting, and the addition of low-frequency vibration reduces the principal force. This is because the cutting force is significantly reduced by superimposed vibration machining. Therefore, in addition to cutting and grinding, highly efficient processing can also be performed in the field of cutting.

A feature of processing equipment that uses such low-frequency vibrations is that shocks are generated by the vibrations. Therefore, when this device is installed in a machine or configured as a handheld device, it is subjected to undesirable vibrations, making it difficult to accurately cut, grind, or cut a workpiece, especially in the case of a handheld device.

Therefore, in the present invention, a holding member is attached to a vibration node of an ultrasonic vibrating unit equipped with a vibrator, a horn, and a tool, and the holding member is slidably inserted into an outer cylinder equipped with a pneumatic device, and the pneumatic device is held. It is formed by a main piston connected to a member, a counterbalancing piston connected to a weight and facing the main piston, and a cylinder chamber that causes both pistons to vibrate at low frequency by the inflow and outflow of compressed air, and the main piston is placed in this cylinder chamber. A first spring that presses the balance piston toward the balance piston side, a second spring that presses the balance piston toward the main piston side, and a third spring that contacts both the main piston and the balance piston.
A spring is provided to eliminate the above problem.

In this case, it is advantageous that the first spring and the second spring have substantially the same spring constant, and that the mass of the ultrasonic vibrator, the holding member plus the main piston, and the mass of the counterbalance piston are substantially the same.

Next, the present invention will be explained with reference to the drawings.

1 indicates a tool consisting of a grindstone, and a horn 2 is fixed to this tool 1 by an appropriate method such as a screw or a taper.
An electrostrictive vibrator 3 is coupled to the horn 2. The ultrasonic vibrating section consists of the above-mentioned tool, horn, and vibrator.

Reference numeral 5 denotes a cylindrical holding member with a bottom, which is attached to the vibration node 4 of the horn 2.

Reference numeral 6 indicates an outer cylinder equipped with a pneumatic device, and a holding member 5 is slidably inserted into this outer cylinder 6. The pneumatic device provided in the outer cylinder 6 has one end connected to the holding member 5.
a main piston 7 coupled to the bottom of the main piston 7;
It includes a counterbalance piston 8 facing each other, and a cylinder chamber 9 in which both pistons are caused to vibrate at a low frequency by the inflow and outflow of compressed air. 10 indicates a weight attached to one end of the balance piston and located outside the cylinder chamber 9.

The cylinder chamber 9 has an air supply hole 1 opened in its inner wall.
1, 12, 13 and exhaust holes 14, 15, 16, 17
is provided at the location shown in the figure. 18 is the air supply port,
19 is a communication passage communicating with the air supply port 18 and the air supply holes 11 and 13, respectively; 20 is a communication path that communicates with the air supply port 18 and the air supply hole 12;
Branch communication passages 21 and 22, which communicate with each other and branch from the middle of the communication passage 19, are provided in the shaft portion of the piston 7, and when the piston 7 is driven, the communication passage 19 and the branch communication passage 20 are opened and closed alternately. Each shows a constricted valve. 23 is an exhaust port, 24 is an exhaust port 23 and exhaust holes 14, 15, 1
6 and 17 show exhaust passages communicating with each other, respectively.

Reference numeral 25 designates a first spring, which is installed in the cylinder chamber 9 so as to press the main piston 7 toward the balance piston. 26 indicates a second spring, which is connected to the counterbalancing piston 8 in the cylinder chamber 9.
is installed so as to press the main piston 7 side.
Both springs have substantially the same spring constant, and the mass of the ultrasonic vibrating portion, the holding member, and the main piston 7, and the mass of the counterbalance piston 8 including the weight 10 are substantially the same.

Reference numeral 27 denotes a third spring, which is disposed between the main piston 7 and the balance piston 8, and is in contact with both.

The above tool vibration machining device connects the ultrasonic vibrating part to the conductor 3.
0 to the ultrasonic oscillator 28, and the air supply port 1
8 is used by connecting it to a compressed air source 29 via a bendable feeding tube 31.

The ultrasonic vibrator and the pneumatic device are each oscillator 2.
8. When driven by the compressed air source 29, ultrasonic vibration is generated due to the mechanical vibration of the vibrator 3 and the amplitude expansion of the horn 2, and the low frequency vibration of the pneumatic device is added to this, causing the tool 1 to generate ultrasonic vibration and low frequency vibration. A superimposed vibration of frequency vibrations is applied, and when the operation of the oscillator 19 is stopped, only low frequency vibrations are applied to the tool 1.

Low frequency vibration occurs in the state shown in the figure, when compressed air enters from the air supply port 18 through the branch communication passage 20 and enters the cylinder chamber 9 from the air supply hole 12. By moving the valve 21 upward, the exhaust holes 15 and 16 communicate with the exhaust port 23. On the other hand, instead of closing the branch communication passage 20, the valve 21 is moved to open the communication passage 19, so that compressed air flows in from the air supply holes 11 and 13. However, in the figure, the main piston 7 is reversed to the upper side, and the balance piston 8 is reversed to the lower side, so that the state shown in the figure is achieved again, and in this way, low frequency vibrations of several Hz to several 100 Hz are advanced.

When low frequency vibration is applied in this way, the second and third springs 26 and 27 exist and cooperate with the first spring 25, thereby forming a system including the ultrasonic vibrating part, the holding member, the main piston, and the weight. The systems of counterbalancing pistons move in opposite directions, causing the respective masses of both systems to move in opposite directions and cancel out the inertial forces. Therefore, the impact caused by vibrations on the outer cylinder can be sufficiently alleviated.

In the above explanation, a grindstone is used as the tool, but saw blades, files, knives, kerchief blades, etc. can also be used, and many materials such as metal, wood, plastic, stone, and rubber can be processed. It happens.

[Brief explanation of the drawing]

The figure is a longitudinal sectional view of the device of the present invention. DESCRIPTION OF SYMBOLS 1... Tool, 2... Horn, 3... Vibrator, 4... Vibration node, 5... Holding member, 6... Outer cylinder, 7... Main piston,
8... Balance piston, 9... Cylinder chamber, 10...
Weight, 25...first spring, 26...second spring, 27...third spring.

Claims (1)

[Claims] 1. A holding member is attached to a vibration node of an ultrasonic vibrating unit equipped with a vibrator, a horn, and a tool, and the holding member is slidably inserted into an outer cylinder equipped with a pneumatic device, and the pneumatic device is held. The main piston is formed by a main piston connected to a member, a counterbalance piston connected to a weight and facing the main piston, and a cylinder chamber that vibrates both pistons at a low frequency by the inflow and outflow of compressed air. A first spring that presses the balance piston toward the balance piston, a second spring that presses the balance piston toward the main piston, and a third spring that contacts the main piston and the balance piston. Tool vibration machining equipment. 2. Claim 1, wherein the first spring and the second spring have substantially the same spring constant, and the mass of the ultrasonic vibrating part, the holding member, plus the main piston, and the mass of the counterbalancing piston are substantially the same. The tool vibration machining device described.