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Publication numberUS3638366 A
Publication typeGrant
Publication dateFeb 1, 1972
Filing dateDec 3, 1969
Priority dateDec 3, 1969
Publication numberUS 3638366 A, US 3638366A, US-A-3638366, US3638366 A, US3638366A
InventorsNorman M Gamache
Original AssigneeNorton Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Lapping method for metallic workpieces
US 3638366 A
Abstract
A process for providing clean lapped surfaces on metallic workpieces supported in operative relation to the working surface of a bonded abrasive lap for sliding and rotary movement relative to such working surface throughout a single continuous lapping operation including a first predetermined time period during which an abrasive slurry is supplied to the working surfaces of the lap and a second predetermined time period during which the working surface of the lap is flooded continuously with a nonabrasive cleaning fluid effective to wash clean the working surface of the lap and the lapped surfaces of the workpieces.
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Description  (OCR text may contain errors)

United States Patent Gamache Feb. 1, 1972 [54] LAPPING METHOD FOR METALLIC WORKPIECES [72] inventor:

[73] Assignee: Norton Company, Worcester, Mass.

[22] Filed: Dec. 3, 1969 [2]] Appl. No.: 881,867

Norman M. Gamache, Worcester, Mass.

Bullard ..Sl/l3l Norton ..5l/l3l [57] ABSTRACT A process for providing clean lapped surfaces on metallic workpieces supported in operative relation to the working surface of a bonded abrasive lap for sliding and rotary movement relative to such working surface throughout a single continuous lapping operation including a first predetermined time period during which an abrasive slurry is supplied to the working surfaces of the lap and a second predetermined time period during which the working surface of the lap is flooded continuously with a nonabrasive cleaning fluid effective to wash clean the working surface of the lap and the lapped surfaces of the workpieces.

1 Claims, 1 Drawing Figure PATENTEU FEB 11972 $638,366

I VENTOR. NORMAN M gAMACHE ATTORNEY LAPPING METHOD FOR METALLIC WORKPIECES BACKGROUND OF THE INVENTION There are two well-known lapping methods for providing lapped surfaces on metallic workpieces of various different sizes and shapes.

One of these methods applies to lapping machines equipped with a bonded abrasive lap, made like a grinding wheel, effective first to remove stock from workpieces and then to produce a clean lapped surface, without the use of a loose abrasive on the working surface of the lap.

The other method is applicable to lapping machines equipped with a metal lap, usually either cast iron or steel, to which a loose abrasive is applied. On such lapping machines, this loose abrasive is usually either combined with a paste or with a liquid vehicle to form a slurry.

SUMMARY OF THE INVENTION The instant invention consists of a new lapping method combining the use of a bonded abrasive lap characteristic of the first well-known method described above with the use of loose abrasive in a slurry or paste characteristic of the second well-known method described above, and also introduces the use of a nonabrasive cleaning fluid to flood the working surface of the lapping element.

This new lapping method is most effective when it is applied to a lapping machine equipped with a relatively hard-bonded abrasive lap, in order to avoid producing excess quantities of loose abrasives from the lap itself, particularly while the working surface of the lap is flooded with a nonabrasive cleaning fluid which may comprise a thin filtered mineral seal oil.

DRAWING The single FIGURE of drawing shows schematically a bonded abrasive lapping element (lap") which is lapping the lower surface of metallic workpiece MP.

The workpiece is held in a holder H, such as the planetary ring holder shown in Norton US. Pat. No. 2,870,580. The lapping action is accomplished by relative sliding motion between the surface to be lapped and the lap in the presence of abrasive particles. A first source of abrasive particles is the lap itself which is selected as noted above, to be of the bonded abrasive rather than of the metallic type. A second source of abrasive is a fluid reservoir containing abrasive grains in a fluid AF. The reservoir has a value V1 and nozzle N] for selectively dispensing fluid to the lap where the lap motion tends to distribute it to the lap/workpiece butting surfaces. The relative sliding motion may be of various directions but in accordance with conventional practice is shown here as rotary/planetary with the lap being driven about a major or central axis of rotation of the machine Al and the workpiece MP being driven about a second local axis A2. Details of the necessary drives and other conventional elements necessary to complete a lap machine are omitted and reference is made to said Norton patent for a description of these.

A reservoir of clear fluid CF with a valve V2 and nozzle N2 for selectively dispensing such clear fluid to the lapping region is also provided. Lapping cycles are carried out with initial feed of abrasive bearing fluid via valve V1, nozzle N1 and with valve V2 closed for a predetermined period of time and the cycles are then finished off with continuous feed of nonabrasive cleaning fluid via valve V2, nozzle N2 and valve VI closed for a second predetermined period of time to wash clean the working (upper) surface of the lap and the lapped (bottom) surface of the metallic workpiece. While this drawing illustrates a single workpiece, it will be understood that multiple workpieces can be simultaneously lapped in a single lapping cycle.

The usual requirement for interrupting the lapping operation to true the bonded abrasive lap can be avoided by applying this new lapping method to a lapping machine equipped with cast iron or other metallic conditioning rings such as those shown and described in US. Pat. Nos. 2,565,590 and 2,870,580, so that lap conditioning is a continuous process during lapping operations according to this new method.

While this new method has been described thus far as it applies to lapping machines equipped with a single lap, it is also applicable to lapping machines equipped with opposing upper and lower bonded abrasive laps arranged in the manner already well known in the art to finish workpieces on opposite sides at the same time in a single lapping operation.

What is claimed is:

l. The method of producing a clean lapped surface on a workpiece with at least one surface to be finished by lapping comprising supporting a given workpiece with its surface to be lapped in operative engagement with a working surface of a given lapping element composed of bonded abrasive material,

producing relative sliding movement between the given workpiece and the given lapping element,

supplying an abrasive slurry to the working surface of the given lapping element only during a first predetermined period of time, and then flooding the working surface of the given lapping element with a nonabrasive cleaning fluid during a second predetermined period of time sufficient to produce a clean lapped surface on the given workpiece.

Patent Citations
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US387555 *Feb 20, 1888Aug 7, 1888 cumminas
US546025 *Sep 10, 1895Rs Of OneOrs of one-third to martin huonker
US1945510 *Oct 5, 1931Feb 6, 1934White S Dental Mfg CoMethod of and mechanism for forming hardened steel
US2565590 *Mar 12, 1948Aug 28, 1951Earl J BullardLapping machine
US2870580 *Apr 18, 1955Jan 27, 1959Pacific Valves IncFlat lapping machine
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4048763 *Feb 19, 1976Sep 20, 1977Jmj Werkzeugmaschinen Gmbh Fuer FeinbearbeitungMethod for surface-, plane-parallel-, and plain lapping
US4053288 *Mar 30, 1976Oct 11, 1977Barron Sr Lee HHand fed glass beveling apparatus
US4920700 *Apr 28, 1988May 1, 1990Hoya CorporationProcess for finishing optical lenses and apparatus therefor
US5603654 *Feb 13, 1995Feb 18, 1997Nec CorporationMethod for supplying a polishing liquid and polishing method using the same
US5833523 *Sep 3, 1996Nov 10, 1998Hykes; Timothy W.For delivering coolant to the working surfaces of a machine tool
US5868608 *Aug 13, 1996Feb 9, 1999Lsi Logic CorporationSubsonic to supersonic and ultrasonic conditioning of a polishing pad in a chemical mechanical polishing apparatus
US5972792 *Oct 18, 1996Oct 26, 1999Micron Technology, Inc.Method for chemical-mechanical planarization of a substrate on a fixed-abrasive polishing pad
US6168502Dec 14, 1998Jan 2, 2001Lsi Logic CorporationSubsonic to supersonic and ultrasonic conditioning of a polishing pad in a chemical mechanical polishing apparatus
US6220934Jul 23, 1998Apr 24, 2001Micron Technology, Inc.Method for controlling pH during planarization and cleaning of microelectronic substrates
US6368194May 17, 2000Apr 9, 2002Micron Technology, Inc.Apparatus for controlling PH during planarization and cleaning of microelectronic substrates
US6716089Apr 24, 2001Apr 6, 2004Micron Technology, Inc.Method for controlling pH during planarization and cleaning of microelectronic substrates
US6913523Mar 22, 2004Jul 5, 2005Micron Technology, Inc.Method for controlling pH during planarization and cleaning of microelectronic substrates
US7214125 *Jun 10, 2005May 8, 2007Micron Technology, Inc.Method for controlling pH during planarization and cleaning of microelectronic substrates
US8123593 *May 7, 2009Feb 28, 2012Zygo CorporationConfiguring of lapping and polishing machines
US20090280721 *May 7, 2009Nov 12, 2009Douglas Martin HoonConfiguring of lapping and polishing machines
EP0064136A2 *Mar 4, 1982Nov 10, 1982International Business Machines CorporationMagnetic disk substrate polishing method and polishing pad therefor
WO1998018159A1 *Oct 17, 1997Apr 30, 1998Micron Technology IncMethod for chemical-mechanical planarization of a substrate on a fixed-abrasive polishing pad
Classifications
U.S. Classification451/57, 451/450, 451/446
International ClassificationB24B37/04
Cooperative ClassificationB24B37/042
European ClassificationB24B37/04B
Legal Events
DateCodeEventDescription
Oct 6, 1988AS02Assignment of assignor's interest
Owner name: PRATT & WHITNEY COMPANY, INC., THE, CHARTER OAK BL
Owner name: WARNER & SWASEY COMPANY, THE
Effective date: 19880706
Oct 6, 1988ASAssignment
Owner name: PRATT & WHITNEY COMPANY, INC., THE, CHARTER OAK BL
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WARNER & SWASEY COMPANY, THE;REEL/FRAME:004993/0091
Effective date: 19880706