EP0354775A2 - Diamond tool - Google Patents
Diamond tool Download PDFInfo
- Publication number
- EP0354775A2 EP0354775A2 EP89308081A EP89308081A EP0354775A2 EP 0354775 A2 EP0354775 A2 EP 0354775A2 EP 89308081 A EP89308081 A EP 89308081A EP 89308081 A EP89308081 A EP 89308081A EP 0354775 A2 EP0354775 A2 EP 0354775A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- diamond
- working surface
- diamond particles
- particles
- paste
- 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.)
- Granted
Links
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/04—Lapping machines or devices; Accessories designed for working plane surfaces
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B9/00—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor
- B24B9/02—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground
- B24B9/06—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain
- B24B9/16—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain of diamonds; of jewels or the like; Diamond grinders' dops; Dop holders or tongs
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
- B24D7/00—Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting otherwise than only by their periphery, e.g. by the front face; Bushings or mountings therefor
- B24D7/02—Wheels in one piece
Definitions
- This invention relates to diamond tools, particularly diamond scaifes.
- a diamond scaife is a tool which comprises a cast iron plate, one surface of which has a paste containing a plurality of small diamond particles uniformly spread across it. The paste is rubbed on to the surface and then worked in with a piece of low quality diamond.
- a diamond scaife is a tool used for polishing diamond.
- a diamond tool comprises an iron-based working surface having a bonding paste of an organic binder uniformly spread across it, the paste containing a plurality of particles of single crystal and polycrystalline diamond which are partially embedded in the iron-based working surface.
- a method of making a diamond tool as described above which includes the steps of providing an iron-based working surface, depositing a layer of a bonding paste of an organic binder on the surface, the bonding paste containing a plurality of single crystal and polycrystalline diamond particles, and causing the diamond particles to become partially embedded in the working surface.
- the abrasive elements for the diamond tool will be constituted by a mixture of single crystal and polycrystalline diamond.
- the paste will constitute a thin film across the iron-based working surface and is believed, in use, to perform some lubricating function.
- the paste will contain the diamond particles which will also be partially embedded in the iron-based working surface. It has been found that use of this tool results in polishing being achieved without the metal surface coming into contact with the diamond or other material being polished.
- the diamond tool is preferably a diamond scaife.
- the working surface may be made of any suitable iron-based material, but is preferably cast iron.
- the paste will have a coherency sufficient to allow it to remain on the working surface without flowing off it. It will act, at least in part, to locate the diamond particles on the working surface and also as a lubricant.
- the paste is constituted by an organic binder which may be any known in the art. Examples of suitable binders include cellulose ethers and esters, phenolic resins, dextrin and other similar materials. One preferred organic binder is methyl cellulose.
- the diamond particles will be fine, i.e. they will generally have a particle size of 40 microns or less. When the diamond tool is to be used for a relatively rough polishing operation, the diamond particles will typically have a size of 10 to 40 microns. For smoothing operations, finer diamond particles of the order of 2 to 10 microns will be used.
- the diamond particles will be made up of a combination of single crystal diamond and polycrystalline diamond.
- the polycrystalline diamond particles will generally be produced by crushing a diamond compact.
- the diamond compact may be one which contains a solvent second phase such as that described in United States Patent No. 3,745,623 and British Patent No. 1,489,130.
- the polycrystalline diamond may also be produced from a thermally stable diamond compact, that is a diamond compact which can withstand a temperature of 1200°C in a vacuum, inert or non-oxidising atmosphere without any significant graphitisation of the diamond occurring. Examples of such compacts are described in United States Patents Nos. 4,224,380, 4,534,773 and British Patent No. 2,158,086. It is preferred that the polycrystalline diamond is thermally stable, particularly of the type described in British Patent No. 2,158,086.
- the diamond tool may be made by a method which forms another aspect of the invention. As described above, this method involves providing an iron-based working surface, depositing a layer of a bonding paste of an organic binder on the surface, the bonding paste containing a plurality of single crystal and polycrystalline diamond particles, and causing the diamond particles to become partially embedded in the working surface. Generally, the diamond particles will be caused to become partially embedded in the working surface by rotating that surface and bringing the rotating surface into contact with a diamond surface which is generally a piece of low quality diamond.
- the bonding paste will preferably be deposited on the working surface in the form of a liquid which contains a solvent and the solvent then allowed to evaporate at least partially, to produce the coherent paste.
- the solvent will vary according to the nature of the organic binder.
- the organic binder will be such that the solvent is water.
- the single crystal diamond particles may be smaller than the polycrystalline diamond particles so that when the particles are caused to become partially embedded in the working surface, the fine single crystal diamond particles tend to locate in spaces between the polycrystalline diamond particles.
- FIG. 1 of this drawing there is shown a cast-iron disc 10 of a diamond scaife which has an upper working surface 12.
- This working surface 12 has a uniform layer of bonding paste of an organic binder uniformly spread across it.
- This bonding paste includes a plurality of diamond particles 14 evenly distributed through it and partially embedded in the working surface 12 of the disc 10.
- the diamond scaife may be made by depositing a first layer 16 on the working surface 12 of the disc 10 - see Figure 2.
- This layer 16 will consist of an organic binder containing a plurality of the polycrystalline diamond particles.
- the layers 16 and 18 are each deposited by providing a liquid mixture of the organic binder, a suitable solvent and the diamond particles, applying that liquid mixture to the relevant surface and allowing the solvent to evaporate leaving a coherent paste layer.
- the diamonds of the two layers are worked into the surface 12 by rotating the disc 10, for example at a speed of about 2000rpm, and bringing that rotating surface into contact with a diamond surface such as that provided by a low quality diamond.
- the resulting product is that illustrated by Figure 1.
- one carat of crushed thermally stable diamond compact containing a silicon second phase (as described in British Patent No. 2,158,086) and of particle size less than 40 microns was rubbed on the cast iron working surface of a scaife with a binder such as dextrin or phenolic resin in a solvent.
- the solvent was allowed to evaporate leaving a coherent paste.
- a paste of fine single crystal diamond particles in water containing methyl cellulose was then applied to the coated surface.
- the water was allowed to evaporate leaving a thin film or layer of coherent methyl cellulose paste containing the diamond particles.
- the coated working surface was then rotated at a speed of 2000rpm and brought into contact with a low quality diamond.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Inorganic Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Polishing Bodies And Polishing Tools (AREA)
- Carbon And Carbon Compounds (AREA)
- Cutting Tools, Boring Holders, And Turrets (AREA)
Abstract
Description
- This invention relates to diamond tools, particularly diamond scaifes.
- A diamond scaife is a tool which comprises a cast iron plate, one surface of which has a paste containing a plurality of small diamond particles uniformly spread across it. The paste is rubbed on to the surface and then worked in with a piece of low quality diamond. A diamond scaife is a tool used for polishing diamond.
- A diamond tool comprises an iron-based working surface having a bonding paste of an organic binder uniformly spread across it, the paste containing a plurality of particles of single crystal and polycrystalline diamond which are partially embedded in the iron-based working surface.
- According to another aspect of the invention, there is provided a method of making a diamond tool as described above which includes the steps of providing an iron-based working surface, depositing a layer of a bonding paste of an organic binder on the surface, the bonding paste containing a plurality of single crystal and polycrystalline diamond particles, and causing the diamond particles to become partially embedded in the working surface.
-
- Figure 1 illustrates a perspective view of a diamond tool of the invention; and
- Figure 2 illustrates a section through the diamond tool during the course of its manufacture.
- The abrasive elements for the diamond tool will be constituted by a mixture of single crystal and polycrystalline diamond. The paste will constitute a thin film across the iron-based working surface and is believed, in use, to perform some lubricating function. The paste will contain the diamond particles which will also be partially embedded in the iron-based working surface. It has been found that use of this tool results in polishing being achieved without the metal surface coming into contact with the diamond or other material being polished.
- The diamond tool is preferably a diamond scaife.
- The working surface may be made of any suitable iron-based material, but is preferably cast iron.
- The paste will have a coherency sufficient to allow it to remain on the working surface without flowing off it. It will act, at least in part, to locate the diamond particles on the working surface and also as a lubricant. The paste is constituted by an organic binder which may be any known in the art. Examples of suitable binders include cellulose ethers and esters, phenolic resins, dextrin and other similar materials. One preferred organic binder is methyl cellulose.
- The diamond particles will be fine, i.e. they will generally have a particle size of 40 microns or less. When the diamond tool is to be used for a relatively rough polishing operation, the diamond particles will typically have a size of 10 to 40 microns. For smoothing operations, finer diamond particles of the order of 2 to 10 microns will be used.
- The diamond particles will be made up of a combination of single crystal diamond and polycrystalline diamond. The polycrystalline diamond particles will generally be produced by crushing a diamond compact. The diamond compact may be one which contains a solvent second phase such as that described in United States Patent No. 3,745,623 and British Patent No. 1,489,130. The polycrystalline diamond may also be produced from a thermally stable diamond compact, that is a diamond compact which can withstand a temperature of 1200°C in a vacuum, inert or non-oxidising atmosphere without any significant graphitisation of the diamond occurring. Examples of such compacts are described in United States Patents Nos. 4,224,380, 4,534,773 and British Patent No. 2,158,086. It is preferred that the polycrystalline diamond is thermally stable, particularly of the type described in British Patent No. 2,158,086.
- The diamond tool may be made by a method which forms another aspect of the invention. As described above, this method involves providing an iron-based working surface, depositing a layer of a bonding paste of an organic binder on the surface, the bonding paste containing a plurality of single crystal and polycrystalline diamond particles, and causing the diamond particles to become partially embedded in the working surface. Generally, the diamond particles will be caused to become partially embedded in the working surface by rotating that surface and bringing the rotating surface into contact with a diamond surface which is generally a piece of low quality diamond.
- The bonding paste will preferably be deposited on the working surface in the form of a liquid which contains a solvent and the solvent then allowed to evaporate at least partially, to produce the coherent paste. The solvent will vary according to the nature of the organic binder. Preferably the organic binder will be such that the solvent is water.
- Generally, two layers of the bonding paste will be deposited on the surface one on top of the other, the layer adjacent the working surface containing the polycrystalline diamond particles and the other layer containing the single crystal diamond particles. In this form of the invention, the single crystal diamond particles may be smaller than the polycrystalline diamond particles so that when the particles are caused to become partially embedded in the working surface, the fine single crystal diamond particles tend to locate in spaces between the polycrystalline diamond particles.
- An embodiment of the invention will now be described with reference to the accompanying drawings. Referring to Figure 1 of this drawing, there is shown a cast-iron disc 10 of a diamond scaife which has an upper working
surface 12. This workingsurface 12 has a uniform layer of bonding paste of an organic binder uniformly spread across it. This bonding paste includes a plurality ofdiamond particles 14 evenly distributed through it and partially embedded in theworking surface 12 of the disc 10. - The diamond scaife may be made by depositing a first layer 16 on the working
surface 12 of the disc 10 - see Figure 2. This layer 16 will consist of an organic binder containing a plurality of the polycrystalline diamond particles. On the layer 16 there is deposited a second layer 18 of an organic binder containing a plurality of the single crystal diamond particles. The layers 16 and 18 are each deposited by providing a liquid mixture of the organic binder, a suitable solvent and the diamond particles, applying that liquid mixture to the relevant surface and allowing the solvent to evaporate leaving a coherent paste layer. The diamonds of the two layers are worked into thesurface 12 by rotating the disc 10, for example at a speed of about 2000rpm, and bringing that rotating surface into contact with a diamond surface such as that provided by a low quality diamond. The resulting product is that illustrated by Figure 1. - In a particular example of the invention, one carat of crushed thermally stable diamond compact containing a silicon second phase (as described in British Patent No. 2,158,086) and of particle size less than 40 microns was rubbed on the cast iron working surface of a scaife with a binder such as dextrin or phenolic resin in a solvent. The solvent was allowed to evaporate leaving a coherent paste. A paste of fine single crystal diamond particles in water containing methyl cellulose was then applied to the coated surface. The water was allowed to evaporate leaving a thin film or layer of coherent methyl cellulose paste containing the diamond particles. The coated working surface was then rotated at a speed of 2000rpm and brought into contact with a low quality diamond. This contact was maintained for 75 minutes to work the polycrystalline diamond particles and the single crystal diamond particles into the working surface. It was found that diamond polishing could be achieved with this scaife without the metal surface coming into contact with the diamond being polished. Further, improved cutting performance was experienced in relation to diamond of 2 carats or larger. This makes the diamond scaife ideally suited for working stressed diamonds.
Claims (10)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ZA885879 | 1988-08-10 | ||
ZA885879 | 1988-08-10 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0354775A2 true EP0354775A2 (en) | 1990-02-14 |
EP0354775A3 EP0354775A3 (en) | 1991-03-27 |
EP0354775B1 EP0354775B1 (en) | 1994-04-27 |
Family
ID=25579366
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP89308081A Expired - Lifetime EP0354775B1 (en) | 1988-08-10 | 1989-08-09 | Diamond tool |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0354775B1 (en) |
IL (1) | IL91187A0 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2255923A (en) * | 1991-05-23 | 1992-11-25 | De Beers Ind Diamond | Scaife for diamond cutting or polishing |
WO2009059384A1 (en) * | 2007-11-05 | 2009-05-14 | Wetenschappelijk En Technisch Onderzoekscentrum Voor Diamant, Inrichting Erkend Bij Toepassing Van De Besluitwet Van 30 Januari 1947 | Method and device for mechanically processing diamond |
CN102676911A (en) * | 2012-05-25 | 2012-09-19 | 广州柴油机厂股份有限公司 | Wear-resistant cast iron disc and production process thereof |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR993724A (en) * | 1948-08-27 | 1951-11-06 | Improvements in the manufacture of abrasive polishers | |
US2863750A (en) * | 1954-10-18 | 1958-12-09 | Sheldon M Booth | Method, composition and apparatus for mechanically setting or resetting diamond particles in a working surface |
GB1161885A (en) * | 1965-12-30 | 1969-08-20 | Paul Michael Troll | Improvements in relating to Abrasives. |
DE3032027A1 (en) * | 1979-08-25 | 1981-03-26 | Kombinat Przemysłu Narzędziowego Vis, Warszawa | METHOD FOR PRODUCING GRINDING TOOLS WITH GALVANIC METAL BINDING |
SU878551A1 (en) * | 1980-03-10 | 1981-11-07 | Львовское Производственное Объединение По Выпуску Искусственных Алмазов И Алмазного Инструмента | Metallic binder for manufacturing diamond tool |
GB2158086A (en) * | 1984-03-30 | 1985-11-06 | De Beers Ind Diamond | Abrasive products |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE775418A (en) * | 1971-11-17 | 1972-03-16 | Caes Henri | METHOD OF HOLDING DIAMOND POWDER ON GRINDING WHEELS. |
-
1989
- 1989-08-02 IL IL91187A patent/IL91187A0/en not_active IP Right Cessation
- 1989-08-09 EP EP89308081A patent/EP0354775B1/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR993724A (en) * | 1948-08-27 | 1951-11-06 | Improvements in the manufacture of abrasive polishers | |
US2863750A (en) * | 1954-10-18 | 1958-12-09 | Sheldon M Booth | Method, composition and apparatus for mechanically setting or resetting diamond particles in a working surface |
GB1161885A (en) * | 1965-12-30 | 1969-08-20 | Paul Michael Troll | Improvements in relating to Abrasives. |
DE3032027A1 (en) * | 1979-08-25 | 1981-03-26 | Kombinat Przemysłu Narzędziowego Vis, Warszawa | METHOD FOR PRODUCING GRINDING TOOLS WITH GALVANIC METAL BINDING |
SU878551A1 (en) * | 1980-03-10 | 1981-11-07 | Львовское Производственное Объединение По Выпуску Искусственных Алмазов И Алмазного Инструмента | Metallic binder for manufacturing diamond tool |
GB2158086A (en) * | 1984-03-30 | 1985-11-06 | De Beers Ind Diamond | Abrasive products |
Non-Patent Citations (1)
Title |
---|
SOVIET INVENTIONS ILLUSTRATED Derwent Publications Ltd. abstract number 82-75992E Ý36¨ Bul.41/7.11.81 * |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2255923A (en) * | 1991-05-23 | 1992-11-25 | De Beers Ind Diamond | Scaife for diamond cutting or polishing |
GB2255923B (en) * | 1991-05-23 | 1994-08-03 | De Beers Ind Diamond | Scaife for diamond cutting or polishing |
WO2009059384A1 (en) * | 2007-11-05 | 2009-05-14 | Wetenschappelijk En Technisch Onderzoekscentrum Voor Diamant, Inrichting Erkend Bij Toepassing Van De Besluitwet Van 30 Januari 1947 | Method and device for mechanically processing diamond |
BE1017837A3 (en) * | 2007-11-05 | 2009-08-04 | Wetenschappelijk En Tech Onder | METHOD AND DEVICE FOR MECHANICALLY PROCESSING DIAMOND. |
RU2483854C2 (en) * | 2007-11-05 | 2013-06-10 | Ветенсхаппелейк Эн Технис Ондерзуксентрум Вор Диамант, Инрихтинг Эркенд Бей Тупассинг Ван Де Беслёйтвет Ван 30 Януари 1947 | Method of diamond surface machining and device to this end |
CN101848791B (en) * | 2007-11-05 | 2013-07-31 | 依据1947年1月30日法令建立的钻石科学技术研究中心 | Method and device for mechanically processing diamond |
US8591288B2 (en) | 2007-11-05 | 2013-11-26 | Wetenschappelijk En Technisch Onderzoekscentrum Voor Diamant, Inrichting Erkend Bij Toepassing Van De Besluitwet Van 30 Januari 1947 | Method and device for mechanically processing diamond |
CN102676911A (en) * | 2012-05-25 | 2012-09-19 | 广州柴油机厂股份有限公司 | Wear-resistant cast iron disc and production process thereof |
CN102676911B (en) * | 2012-05-25 | 2013-11-13 | 广州柴油机厂股份有限公司 | Wear-resistant cast iron disc and production process thereof |
Also Published As
Publication number | Publication date |
---|---|
IL91187A0 (en) | 1990-03-19 |
EP0354775B1 (en) | 1994-04-27 |
EP0354775A3 (en) | 1991-03-27 |
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