US2097803A - Grinding wheel - Google Patents

Grinding wheel Download PDF

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Publication number
US2097803A
US2097803A US6441A US644135A US2097803A US 2097803 A US2097803 A US 2097803A US 6441 A US6441 A US 6441A US 644135 A US644135 A US 644135A US 2097803 A US2097803 A US 2097803A
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United States
Prior art keywords
resinoid
wheel
bond
zones
grinding wheel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US6441A
Inventor
Sanford Baalis
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Saint Gobain Abrasives Inc
Original Assignee
Norton Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to NL42790D priority Critical patent/NL42790C/xx
Application filed by Norton Co filed Critical Norton Co
Priority to US6441A priority patent/US2097803A/en
Priority to DED72127D priority patent/DE722684C/en
Priority to FR803212D priority patent/FR803212A/en
Priority to FR803213D priority patent/FR803213A/en
Priority to GB4484/36A priority patent/GB456950A/en
Application granted granted Critical
Publication of US2097803A publication Critical patent/US2097803A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D5/00Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor
    • B24D5/02Wheels in one piece
    • B24D5/04Wheels in one piece with reinforcing means
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D18/00Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D18/00Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
    • B24D18/0009Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for using moulds or presses
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D18/00Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
    • B24D18/0045Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for by stacking sheets of abrasive material
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/02Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent
    • B24D3/20Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially organic
    • B24D3/28Resins or natural or synthetic macromolecular compounds
    • B24D3/285Reaction products obtained from aldehydes or ketones
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D5/00Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D5/00Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor
    • B24D5/02Wheels in one piece
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D5/00Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor
    • B24D5/12Cut-off wheels

Definitions

  • WIT-Mesem BAAL is @A NFORD Patented Nov. 2, 1937'4 vPATENT OFFICE Norton Company, Worcester, Mass., a corporation of Massachusetts Application February 14, 1935. serial No. 6,441
  • This invention relates to grinding wheels and more particularly to a composite grinding wheel for use as a cutting-off wheel whichhas an uter annular grinding portion of diamond grains bonded by an organic bond and an inner central supporting body of a moldable, heat-settable ⁇ marily comprises the bulk of the article.
  • These materials of the respective zones or portions of the wheel may be 'combined and shaped into a grinding wheel by suitable means and methods.
  • the wheel may ,be made in accordance with a method which involves hot pressing a mixture of ⁇ diamond grains and resinoid bond in a mold in situ with a preformed resinoid core to form a hard, dense mass and heat setting the resinoid.
  • Fig.l l is a plan view of a grinding wheel embodying my invention.
  • Fig. 2 is a cross-sectional view, on an enlarged scale, taken on the line 2 2 of Fig. 1. l0
  • a composite grinding wheel of this type having a peripheral annular abrasive body of resinoid bonded diamond grains and an inner zone or central supporting ⁇ body ⁇ of a resinoid 15 composition integrally united therewith, in which there is incorporated suitable granular inert material in such an amount that the relative shrinkages between the inner vand outer zones are-substantially equalized. That is, the ingredients of 20 the inner and outer zones are so selected and proportioned, and preferably in equal volume percentages in the two zones, that they may be formed into a unitary body of substantially the same structure and shinkage throughout.
  • V 25 Referring Vto the drawing, which shows one 4specific embodiment of my invention, I have there illustrated a' grinding wheel having an outer grinding portion or rim lll nof resinoid bonded diamond granules and a center portion l2 30 of a resinoid composition interspersed with granular inert material. A central holei3 is provided, in the portion l2 for the subsequent mounting of the complete'wheel on a spindle.
  • I may utilize any mineral or non-mmeral substances which do not change in size materially under the temperature conditions employed during hot pressing'; and, for example, I may em- 60 ploy such granular materials as silicon carbide, crystalline alumina or quartz sand. It is an essential feature -of the invention that the volumel percentages of bond and grains in the two zones ofd the wheel shall be sulclently and 50% by volume of bond, then one should use 50% by volume of bond and 50% by volume of granular ller in the inner zone. identical shrinkages. Reasonable variations in these proportions are, of course, permissible.
  • composition which will be suitablefor forming a satisfactory grinding wheel having substantially equal shrinkage throughout, I may utilize the ingredients in the following proportions:
  • the materials of the two portions or zones arev mixed separately and in a dry condition until the respective grains of diamond and 1111er have each been thoroughly incorporated with the particular resinoid bond employed therewith which is in a powdered or finely divided condition.
  • the cntral support or inner zone of the wheel is rst formed by 'pressurein a cylindrical mold of the size ydesired for the wheel center which has resulted in a body having compact and reasonably dense structure.
  • the dry resinoid mixture as above preparedland incorporating the granular illler is molded by a prelimicentral support.
  • this invention Y applies to a composite wheel structure in which the central non-abrasive portion shrinks either more or less than does the outer diamond rim portion during cooling of the bond in each of the respective portions after it has been matured by heat. If the composition of the central zone contained materials which served to prevent its contracting as much as does the cured diamond and resinoid mixture in the rim, then the greater rim-,shrinkage would place the center portion under compression and cause warpage or buckling of this center portion. Similarly, if the center portion should shrink more than the outer rim, then either the rim would be placed under radial tension to produce warping ofthe center, orthe two zones might even separate due to the.
  • each bond should occupy the same percentage per unit of volume in each of the zones.
  • the grain size of the diamonds and that of the granular filler in the respective zones are substantially the same size. It is ⁇ important, however, if strength is to be considered. that the grains of granular inert material in the inner zone be made of a fine grit size, whether or not the diamond grains employed in the rim portion are small in size. Nevertheless, there must be the ysame total volume of solids per unit of volume in each of the zones. Also, if the resinoids differ in their shrinkage coefiicients, then due allowance will be made for this in determiningf the volume percentages thereof.
  • a thin cutting ofi grinding wheel compris- 5 ing an outer annular abrasive zone of diamond p grains and a reacted resinoid bond compacted Xand proportioned to provide a dense body and a central supporting zone of silicon carbide grains

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Polishing Bodies And Polishing Tools (AREA)

Description

Nv 2, 19371 B. sANFoRb 2,097,803
- GRINDING WHEEL Fiied Feb. 14, y19:55
WIT-Mesem BAAL is @A NFORD Patented Nov. 2, 1937'4 vPATENT OFFICE Norton Company, Worcester, Mass., a corporation of Massachusetts Application February 14, 1935. serial No. 6,441
2 Claims.
This invention relates to grinding wheels and more particularly to a composite grinding wheel for use as a cutting-off wheel whichhas an uter annular grinding portion of diamond grains bonded by an organic bond and an inner central supporting body of a moldable, heat-settable` marily comprises the bulk of the article. These materials of the respective zones or portions of the wheel may be 'combined and shaped into a grinding wheel by suitable means and methods. For example, the wheel may ,be made in accordance with a method which involves hot pressing a mixture of `diamond grains and resinoid bond in a mold in situ with a preformed resinoid core to form a hard, dense mass and heat setting the resinoid.
3-0 It is found, however, that such a method presents certain mechanical diftlculties when apl- `plied to the manufacture of thin cutting-off wheels, which due to the slender dimensions of the article together with the different coeilicients of expansion and unequal shrinkages of' the cured materials in the inner and outer zones of the body and the different maturity characterstics possessed by each of the resinoid compositions used, results in a warped final product. It is accordingly an object of my invention to overcome such dimculties and provide va composite grinding wheel of this type which will not be warped to a detrimental extent after manufacture-and which may be 4economically and easily produced. l
v It is a further object-of my--invention to provide a diamond abrasive wheel of a composite structure havingv a plurality of zones as well as a method of making such an article in which `the shrinkages and coefllcients of expansion thereof may be made substantially equal, and to provide a wheel structure having substantially uniform shrinkage throughout.` l
With these and `further objects in view, as
will be apparent in the following disclosure, my
invention resides in the subject matter described hereinafter and covered by the claims appended hereto.
Referring to the drawing, which illustrates one embodiment of my invention and in which like 5 reference numerals indicatelike parts:
Fig.l l is a plan view of a grinding wheel embodying my invention; and
Fig. 2 is a cross-sectional view, on an enlarged scale, taken on the line 2 2 of Fig. 1. l0
In accordance with my invention, I propose to make a composite grinding wheel of this type having a peripheral annular abrasive body of resinoid bonded diamond grains and an inner zone or central supporting `body `of a resinoid 15 composition integrally united therewith, in which there is incorporated suitable granular inert material in such an amount that the relative shrinkages between the inner vand outer zones are-substantially equalized. That is, the ingredients of 20 the inner and outer zones are so selected and proportioned, and preferably in equal volume percentages in the two zones, that they may be formed into a unitary body of substantially the same structure and shinkage throughout. V 25 Referring Vto the drawing, which shows one 4specific embodiment of my invention, I have there illustrated a' grinding wheel having an outer grinding portion or rim lll nof resinoid bonded diamond granules and a center portion l2 30 of a resinoid composition interspersed with granular inert material. A central holei3 is provided, in the portion l2 for the subsequent mounting of the complete'wheel on a spindle.
'While various resinoid materials may be selected` 35 for bondingthe diamond grains inthe outer rim portion ofthe wheel and for making the center portion thereof and uniting the granular material incorporated therein, I preferably employ a fusible, potentially reactive, heat-settable resin- 40 oidof the phenclictype, such as is commonly known'in the art under the trade-mark Bakelite and obtained as .a condensation product formed by the reaction of phenol andformaldehyde or,Vv by that of their omologues. For the 45 granular inert material in he center portion, I may utilize any mineral or non-mmeral substances which do not change in size materially under the temperature conditions employed during hot pressing'; and, for example, I may em- 60 ploy such granular materials as silicon carbide, crystalline alumina or quartz sand. It is an essential feature -of the invention that the volumel percentages of bond and grains in the two zones ofd the wheel shall be sulclently and 50% by volume of bond, then one should use 50% by volume of bond and 50% by volume of granular ller in the inner zone. identical shrinkages. Reasonable variations in these proportions are, of course, permissible.
As a specific example of a composition which will be suitablefor forming a satisfactory grinding wheel having substantially equal shrinkage throughout, I may utilize the ingredients in the following proportions:
' Outereone Percent by volume Diamond grains (100 mesh grit size) 50 Resinoid bond (phenolic resinoid) 50 Imicr zone Percent by volume Silicon carbide (100 mesh grit size) 50 Resinoid bond (phenolic resinoid) 50 It will, of course, be obvious that different grain sizes of the diamonds and the granular filler may be employed and that the various kinds of resinoids may be used accordingly, as is well known in the art. The density and structure of the product are determined by the nature of the ingradients employed as well as their relative proportions. However, it is preferred to form a wheel structure in which the materials of the two portions are compacted into asubstantially solid, dense mass, that is, one having practically zero porosity.
The materials of the two portions or zones arev mixed separately and in a dry condition until the respective grains of diamond and 1111er have each been thoroughly incorporated with the particular resinoid bond employed therewith which is in a powdered or finely divided condition. The cntral support or inner zone of the wheel is rst formed by 'pressurein a cylindrical mold of the size ydesired for the wheel center which has resulted in a body having compact and reasonably dense structure. Thus, by that method, the dry resinoid mixture as above preparedland incorporating the granular illler is molded by a prelimicentral support. During this operation, care yshould be taken to keep the resinoid ybond from completely reacting so as not to become converted into the infuslble state. 'I'his preformed body I2 is then set into a mold cavity of a size to form the complete wheel and an iron core is inserted into the .center hole i3 to preventdeformation while under the molding pressure. The dry mixture of diamonds and resinoid is then packed into the mold and pressed in place by a suitable hand implement around the outer periphery of the solid center, after which the whole1wheel v mass is then subjected to heatand pressure in naccordance with the usual hot pressing practice which is employed in the art, sc that the various sections are molded together and matured into a hard, integral structure of the desired density. Such procedure as thatv of my prior Patent 1,981,970 may also be used.
It is also feasible to make such a wheel by the following method in which a thin metal ring or annular band is placed in the mold' around and .spaced from the-arbor pin, the diameter and" height of this band being the same as the cor- This insures of the desired grinding properties.
nary compacting operation to produce a strong --ing composition which includes the inert granular material." 'Ihe mixture is then tamped in position. Thereafter, the ring is removed from the mold and the remainder of the mold cavity is then lled with the proper amount of diamond and resinoid mixture to make a rim portion The wheel material is then subjected to heat and pressure whereby the material is molded into an integral unitary body in which the resinoid bond in the two portions is matured and set to its inal iniusible condition.
It will now be appreciated that this invention Y applies toa composite wheel structure in which the central non-abrasive portion shrinks either more or less than does the outer diamond rim portion during cooling of the bond in each of the respective portions after it has been matured by heat. If the composition of the central zone contained materials which served to prevent its contracting as much as does the cured diamond and resinoid mixture in the rim, then the greater rim-,shrinkage would place the center portion under compression and cause warpage or buckling of this center portion. Similarly, if the center portion should shrink more than the outer rim, then either the rim would be placed under radial tension to produce warping ofthe center, orthe two zones might even separate due to the.
two zones. That is, each bond should occupy the same percentage per unit of volume in each of the zones. For convenience of manufacture, it is also desirable to have the grain size of the diamonds and that of the granular filler in the respective zones of substantially the same size. It is`important, however, if strength is to be considered. that the grains of granular inert material in the inner zone be made of a fine grit size, whether or not the diamond grains employed in the rim portion are small in size. Nevertheless, there must be the ysame total volume of solids per unit of volume in each of the zones. Also, if the resinoids differ in their shrinkage coefiicients, then due allowance will be made for this in determiningf the volume percentages thereof. Hence, the main object of this invention is satisfied by so selecting and proportioning the ingredients that the coelcients of shrinkage of the two zones in the completed articlare substantiallylalike. v Y' Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: -1 Vl. Agthinucuttingoif grinding wheel comprising outer annular abrasive zone of diamond grains and a reacted resinoid bond compacted and proportioned to provide al dense body and a central supporting zone of a granular filler other than diamond and reacted resinoid'bond compacted `into a rigid support for the outer zone,
said l:granular filler and its bond Ain the inner zone being so proportioned that lthe bond occuples substantially the same volume percentage as does the bond of the abrasive zone.
2. A thin cutting ofi grinding wheel compris- 5 ing an outer annular abrasive zone of diamond p grains and a reacted resinoid bond compacted Xand proportioned to provide a dense body and a central supporting zone of silicon carbide grains
US6441A 1935-02-14 1935-02-14 Grinding wheel Expired - Lifetime US2097803A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
NL42790D NL42790C (en) 1935-02-14
US6441A US2097803A (en) 1935-02-14 1935-02-14 Grinding wheel
DED72127D DE722684C (en) 1935-02-14 1936-02-14 Process for the production of resin-bonded diamond grit grinding wheels, in particular cutting wheels
FR803212D FR803212A (en) 1935-02-14 1936-02-14 Composite wheel and its manufacturing process
FR803213D FR803213A (en) 1935-02-14 1936-02-14 Grinding wheel and its manufacturing process
GB4484/36A GB456950A (en) 1935-02-14 1936-02-14 Composite grinding wheels and methods of making the same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US6441A US2097803A (en) 1935-02-14 1935-02-14 Grinding wheel

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US2097803A true US2097803A (en) 1937-11-02

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DE (1) DE722684C (en)
FR (2) FR803213A (en)
GB (1) GB456950A (en)
NL (1) NL42790C (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2496234A (en) * 1944-05-15 1950-01-31 Carborundum Co Abrasive articles and methods of manufacturing the same
US2913858A (en) * 1957-09-04 1959-11-24 Nat Broach & Mach Gear honing tool
US3898773A (en) * 1973-08-28 1975-08-12 Swarovski Tyrolit Schleif Grinding disk
US4369046A (en) * 1979-06-15 1983-01-18 Abrasives International N.V. Process for making an abrasive grinding wheel
US4988370A (en) * 1984-05-31 1991-01-29 Minnesota Mining And Manufacturing Company Alumina bonded abrasive for cast iron
US5139536A (en) * 1981-12-15 1992-08-18 Minnesota Mining And Manufacturing Company Alumina bonded abrasive for cast iron
US5139539A (en) * 1981-12-15 1992-08-18 Minnesota Mining And Manufacturing Company Alumina bonded abrasive for cast iron
US5834569A (en) * 1995-03-21 1998-11-10 Norton Company Grinding wheel for flat glass beveling
US20030162488A1 (en) * 2000-01-17 2003-08-28 Georges Bancon Abrasive grindstone and method for making same
US6890250B1 (en) * 1998-09-03 2005-05-10 Ehwa Diamond Ind., Co., Ltd. Diamond blade having rim type cutting tip for use in grinding or cutting apparatus
CN108994747A (en) * 2018-08-01 2018-12-14 江苏三锐研磨科技有限公司 A kind of resin grinding wheel shaping method that stock removal compensates automatically

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1120312B (en) * 1956-02-28 1961-12-21 Carborundum Co Process for the production of cut-off wheels
DE3741279A1 (en) * 1987-12-05 1989-06-15 Jochen C Dzierzon Abrasive disc (grinding wheel)
DE3836587A1 (en) * 1988-10-27 1990-05-03 Winter & Sohn Ernst INSIDE HOLE SAW
MY126040A (en) * 1999-06-01 2006-09-29 Neomax Co Ltd Magnet member cutting method and magnet member cutting apparatus.
JP6684895B2 (en) * 2015-08-21 2020-04-22 アウグスト リュッゲベルク ゲーエムベーハー ウント コンパニー カーゲー Polishing tool and method of manufacturing this type of polishing tool
CN108453619B (en) * 2017-12-30 2020-02-21 苏州赛尔科技有限公司 Thinning grinding wheel for sapphire substrate

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2496234A (en) * 1944-05-15 1950-01-31 Carborundum Co Abrasive articles and methods of manufacturing the same
US2913858A (en) * 1957-09-04 1959-11-24 Nat Broach & Mach Gear honing tool
US3898773A (en) * 1973-08-28 1975-08-12 Swarovski Tyrolit Schleif Grinding disk
US4369046A (en) * 1979-06-15 1983-01-18 Abrasives International N.V. Process for making an abrasive grinding wheel
US5139536A (en) * 1981-12-15 1992-08-18 Minnesota Mining And Manufacturing Company Alumina bonded abrasive for cast iron
US5139539A (en) * 1981-12-15 1992-08-18 Minnesota Mining And Manufacturing Company Alumina bonded abrasive for cast iron
US4988370A (en) * 1984-05-31 1991-01-29 Minnesota Mining And Manufacturing Company Alumina bonded abrasive for cast iron
US5834569A (en) * 1995-03-21 1998-11-10 Norton Company Grinding wheel for flat glass beveling
US6890250B1 (en) * 1998-09-03 2005-05-10 Ehwa Diamond Ind., Co., Ltd. Diamond blade having rim type cutting tip for use in grinding or cutting apparatus
US20030162488A1 (en) * 2000-01-17 2003-08-28 Georges Bancon Abrasive grindstone and method for making same
US6840850B2 (en) * 2000-01-17 2005-01-11 Saint-Gobain Abrasifs Technologie Et Services Abrasive grindstone and method for making same
CN108994747A (en) * 2018-08-01 2018-12-14 江苏三锐研磨科技有限公司 A kind of resin grinding wheel shaping method that stock removal compensates automatically

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Publication number Publication date
DE722684C (en) 1942-07-16
GB456950A (en) 1936-11-18
NL42790C (en)
FR803213A (en) 1936-09-25
FR803212A (en) 1936-09-25

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