Device for vibrating materials to be ground

• US 5,165,205 A
• Filed: 10/28/1988
• Issued: 11/24/1992
• Est. Priority Date: 06/24/1987
• Status: Expired due to Fees

• Current Assignee: Research Development Corporation Of Japan (Japan Science And Technology Agency)
• Original Assignee: Research Development Corporation Of Japan (Japan Science And Technology Agency)
• Inventors: Suzuki, Kiyoshi, Nakagawa, Takeo, Ohmori, Hitoshi
• Primary Examiner(s): Rose, Robert
• Application Number:
  US07/269,145
• Time in Patent Office: 1,488 Days
• Field of Search: 51/109 R, 51/230, 51/59 SS, 51/240 R, 51/58, 51/60, 51/121, 51/283 R, 51/217 S, 51/34 R, 366/108, 366/111, 366/112
• US Class Current: 451/392
• CPC Class Codes: B23Q 1/34 Relative movement obtained by use of deformable elements, e.g. piezoelectric, magnetostrictive, elastic or thermally-dilatable elements sensitive elements capable of producing movement or displacement for purposes not limited to measurement G12B1/00
• CPC Class Codes: B23Q 1/36 Springs
• CPC Class Codes: B23Q 15/013 Control or regulation of feed movement B23Q15/12 takes precedence
• CPC Class Codes: B24B 1/04 subjecting the grinding or polishing tools, the abrading or polishing medium or work to vibration, e.g. grinding with ultrasonic frequency polishing or abrading surfaces on work by means of tumbling apparatus B24B31/00, involving oscillating or vibrating containers B24B31/06; superfinishing surfaces on work, e.g. by means of abrading blocks reciprocating with high frequency, B24B35/00
• CPC Class Codes: B24B 35/005 for making three-dimensional objects by electroerosion B23H5/04
• CPC Class Codes: B24B 7/228 for grinding thin, brittle parts, e.g. semiconductors, wafers grinding edges of thin, brittle parts B24B9/065

Abstract

A device for vibrating a workpiece to be processed, serves as a workpiece table to be used to processing the workpiece by means of a rotating tool having a grindstone. The device comprises a table for supporting the workpiece and a base to be detachably furnished to the table of a processing machine. The table is supported on the base via a plurality of piezoelectric actuators each of which is connected electrically to an external controller for vibrating the workpiece being processed by actuating selectively a driving voltage from the controller. The piezoelectric actuator is a laminated piezoelectric element, at least one end of which is secured to the base.

Claims

1. A device for vibrating a workpiece to be ground with a rotating tool having a grindstone on a processing machine having a machine table, said device comprising a support table for supporting the workpiece;

a base to be detachably mounted on the machine table of the processing machine;

a plurality of piezoelectric actuators for supporting said support table on said base, each of said plurality of piezoelectric actuators being electrically connected to an external controller for receiving a driving voltage therefrom for vibrating the workpiece being ground, and each of said plurality of piezoelectric actuators comprising a plurality of laminated elements and opposite ends secured to said support table and said base, respectively; and

spring means for securing a respective one of said opposite ends to said support table with a pre-pressure to prevent separation of the respective one of said opposite ends from said support table upon vibration of said support table.

2. A device for vibrating a workpiece to be ground with a rotating tool having a grindstone on a processing machine having a machine table, said device comprising a support table for supporting the workpiece;

a base to be detachably mounted on the machine table of the processing machine;

a plurality of piezoelectric actuators for supporting said support table on said base, each of said plurality of piezoelectric actuators being electrically connected to an external controller for receiving a driving voltage therefrom for vibrating the workpiece being ground, and each of said plurality of piezoelectric actuators comprising opposite ends connected to said support table and said base, respectively, and a plurality of cylindrical laminated elements having central holes, a bolt having a shank and extending through said central holes and screwed into a respective hole in said support table; and

spring means provided on an outer periphery of said shank for securing a respective one of said opposite ends to said support table with a pre-pressure.

3. A device for vibrating a workpiece to be ground with a rotating tool having a grindstone on a processing machine having a machine table, said device comprising a support table for supporting the workpiece;

a base to be detachably mounted on the machine table of the processing machine;

a plurality of piezoelectric actuators for supporting said support table on said base, each of said plurality of piezoelectric actuators being electrically connected to an external controller for receiving a driving voltage therefrom for vibrating the workpiece being ground, and each of said plurality of piezoelectric actuators being formed as a Langevin piezostack having opposite ends secured to said support table and said base, respectively; and

bolt means for securing a respective one of said opposite ends to said support table with a pre-pressure.

4. A device for vibrating a workpiece to be ground with a rotating tool having a grindstone on a processing machine having a machine table, said device comprising a support table for supporting the workpiece;

a base to be detachably mounted on the machine table of the processing machine; and

a plurality of piezoelectric actuators for supporting said support table on said base; and

an external controller electrically connected with each of said plurality of piezoelectric actuators for communicating driving voltage thereto for vibrating the workpiece being ground, said external controller comprising electric control means including a switching circuit for each of said piezoelectric actuators, amplifier means connected with said electric control means, and computer means for controlling an output of said power amplifier means to a respective one of said plurality of piezoelectric actuators to thereby control a voltage level communicated to the respective one of said plurality of piezoelectric actuators.

5. A device as claimed in claim 4, further comprising a function generator for controlling an output frequency of said power amplifier means.

6. A device for vibrating a workpiece to be ground with a rotating tool having a grindstone on a processing machine having a machine table, said device comprising a support table for supporting the workpiece;

a base to be detachably mounted on the machine table of the processing machine;

a plurality of piezoelectric actuators for supporting said support table on said base, each of said plurality of piezoelectric actuators being electrically connected to an external controller for receiving a driving voltage therefrom for vibrating the workpiece being ground; and

grinding resistance detecting means located between said base and the machine table of the processing machine and connected with said external controller for separately controlling the driving voltage to each piezo electric actuator in accordance with a grinding resistance and each of said plurality of piezoelectric actuators comprising a plurality of laminated elements and opposite ends secured to said support table and said base, respectively.

7. A device as claimed in claim 6, wherein said grinding resistance detecting means comprises a displacement element for detecting vibration-caused displacement of said base.

8. A device for vibrating a workpiece to be ground with a rotating tool having a grindstone on a processing machine having a machine table, said device comprising a support table for supporting the workpiece;

a base to be detachably mounted on the machine table of the processing machine;

a plurality of piezoelectric actuators for supporting said support table on said base; and

an external controller electrically connected with each of said plurality of piezoelectric actuators for communicating driving voltage thereto for vibrating the workpiece being ground, said external controller comprising means for separately controlling time of actuation of said piezoelectric actuators and voltage levels communicated to said piezoelectric actuators and each of said plurality of piezoelectric actuators comprising a plurality of laminated elements and opposite ends secured to said support table and said base, respectively.

9. A device as claimed in claim 8, wherein said base comprises a box body having a bottom and side walls, said support table is placed in the center of said box body, and said plurality of piezoelectric actuators includes a first group of piezoelectric actuators extending between first opposite side wall and said support table in an X-direction, a second group of piezoelectric actuators extending between second opposite wall and said support table in a Y-direction, and a third group of piezoelectric actuators extending between said bottom and said support table, each piezoelectric actuator of said first, second and third groups of piezoelectric actuators having opposite ends connected with said base and said support table, respectively.

10. A device as claimed in claim 8, wherein said base comprises a disc body having an upper surface, said support table having a lower surface and being placed above said disc body, said plurality of piezoelectric actuators extending between said upper surface of said disc body and said lower surface of said support table and having opposite ends connected with said upper surface of said disc body and said lower surface of said support table, respectively.