Patent USRE29808E successfully refreshed from Google Patents.
USRE29808E
Expired / Lapsed
US
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Hollow body grinding materials
Assignee: Norddeutsche Schleifmittel-Industrie Christiansen and Co
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Filing: 1977-09-12
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Granted: 1978-10-24
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Expires: 1997-09-12
Abstract
Abstract A grinding material comprising a multiplicity of hollow bodies whose walls are formed of abrasive grains and a bonding means and are arranged to be stable in resistance to grinding forces.
Inventors
- 👤 Eckhard Wagner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:42
CPC Classifications
B; B24; B24D; B24D7/00; B24D11/00; C; C09; C09K; C09K3/00; C09K3/14; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/252
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
155 words
A grinding material comprising a multiplicity of hollow bodies whose walls contain .Iadd.substantially therein .Iaddend.abrasive grains in an amount of more than 50% of the wall surface and a bonding means selected from the group consisting of a synthetic resin, a ceramic binder and a metallic binder .[.and are.]. .Iadd.for bonding said abrasive grains to each other at said wall surface, said walls being .Iaddend. arranged to be stable in resistance to grinding forces, the mean diameter of said hollow bodies .[.are.]. measured parallel to a grinding surface .[.lies.]. .Iadd.lying .Iaddend.between 0.1 and 8 mm and .[.is.]. .Iadd.being .Iaddend.not more than 50 times the mean grain diameter, .[.and the abrasive grains are contained substantially within the walls of the hollow bodies.]. .Iadd.whereby during grinding a multiplicity of fresh abrasive grains become continuously available at the grinding surface wherein the grinding action of the grinding surface depends exclusively on the size of the abrasive grains.Iaddend. .
Claim 2
Dependent Claim
155 words
A grinding material comprising a multiplicity of hollow bodies whose walls contain .Iadd.substantially therein .Iaddend.abrasive grains in an amount of more than 50% of the wall surface and a bonding means selected from the group consisting of a synthetic resin, a ceramic binder and a metallic binder .[.and are.]. .Iadd.for bonding said abrasive grains to each other at said wall surface, said walls being .Iaddend. arranged to be stable in resistance to grinding forces, the mean diameter of said hollow bodies .[.are.]. measured parallel to a grinding surface .[.lies.]. .Iadd.lying .Iaddend.between 0.1 and 8 mm and .[.is.]. .Iadd.being .Iaddend.not more than 50 times the mean grain diameter, .[.and the abrasive grains are contained substantially within the walls of the hollow bodies.]. .Iadd.whereby during grinding a multiplicity of fresh abrasive grains become continuously available at the grinding surface wherein the grinding action of the grinding surface depends exclusively on the size of the abrasive grains.Iaddend. .
Claim 3
Dependent Claim
30 words
A grinding material as claimed in claim 1 wherein the thickness of the walls of the hollow bodies is on average less than 10 times the mean abrasive grain diameter.
Claim 4
Dependent Claim
23 words
A grinding material of claim 2 wherein the abrasive grains are disposed in the walls of the hollow bodies substantially in one layer.
Claim 5
Dependent Claim
25 words
A grinding material as claim in claim 1 wherein the abrasive grains are contained in the walls of the hollow bodies in a tightly-packed arrangement.
Claim 6
Dependent Claim
24 words
The grinding material of claim 4 wherein the bonding means content of the walls by weight is not greater than twice their grain content.
Claim 7
Dependent Claim
39 words
A grinding material as claim in claim 1 wherein the hollow body walls each surround a carrier particle, whose mechanical strength of resistance to the stresses occurring during grinding is substantially less than that of the hollow body walls.
Claim 8
Dependent Claim
34 words
A grinding material as claimed in claim 1 wherein all the constituents of the hollow bodies not participating in the formation of the walls are more easily removable under grinding conditions than the walls.
Claim 9
Dependent Claim
47 words
A grinding material as claimed in claim 7 wherein the frictional stress produced at a surface to be ground by the constituents of the hollow bodies not participating in the formation of the walls is less than a fifth of the frictional stress caused by the walls.
Claim 10
Dependent Claim
14 words
A grinding material as claimed in claim 6 wherein the carrier particle is thin-walled.
Claim 11
Dependent Claim
25 words
A grinding material as claimed in claim 7 wherein at least some of the hollow bodies contain a substance which is fluid under grinding conditions.
Claim 12
Dependent Claim
27 words
A grinding material as claimed in claim 7 wherein at least some of the hollow bodies contain a substance which is in powder form under grinding conditions.
Claim 13
Dependent Claim
36 words
A grinding material as claimed in claim 1 wherein the mean overall diameter of the hollow bodies measured parallel to a grinding surface is about three to 50 times as large as the mean grain diameter.
Claim 14
Dependent Claim
20 words
A grinding tool made from the grinding material as claim in claim 1 wherein the hollow bodies are bonded together.
Claim 15
Dependent Claim
25 words
A grinding tool as claimed in claim 13 wherein the hollow bodies are bonded to a base material to form a grinding or abrasive belt.
Claim 16
Dependent Claim
20 words
A grinding tool as claimed in claim 13 wherein the hollow bodies are bonded together to form a grinding body.
Claim 17
Dependent Claim
19 words
The grinding material of claim 1 wherein said hollow bodies are of a copolymer having abrasive grains of corundum.
Claim 18
Dependent Claim
57 words
A process for the production of a grinding material comprising expanding polymeric material to form a multiplicity of hollow bodies having a diameter of 0.1-8.0 mm, coating said hollow bodies with abrasive grains so that said abrasive grains are substantially in one layer, and depositing said coated material onto a substrate having a layer of bonding material.
Claim 19
Dependent Claim
57 words
A process for the production of a grinding material comprising expanding polymeric material to form a multiplicity of hollow bodies having a diameter of 0.1-8.0 mm, coating said hollow bodies with abrasive grains so that said abrasive grains are substantially in one layer, and depositing said coated material onto a substrate having a layer of bonding material.
Claim 20
Dependent Claim
12 words
A process according to claim 17 wherein said substrate is a belt.
Claim 21
Dependent Claim
14 words
A process according to claim 17 wherein said hollow bodies contain a grinding adjuvant.
Claim 22
Dependent Claim
154 words
A process as claimed in claim 17 wherein the abrasive grains are bonded by means of an age-hardening bonding material to the surfaces of hollow thermoplastic beads and the hollow bodies thereby formed are next heated to a temperature at which the hollow bead melts but the bonding material remains sufficiently firm. .Iadd.21. A grinding material as claimed in claim 1, wherein the hollow bodies are individual hollow spheres. .Iaddend. .Iadd.22. A grinding material as claimed in claim 1, wherein each hollow body consists of a thin walled bubble type carrier particle and said abrasive grains bonded to the walls of said carrier particle by said bonding means. .Iaddend..Iadd. 23. A grinding material as claimed in claim 1, wherein the bonding means is a synthetic resin and the abrasive grains are selected from the group consisting of molten aluminum oxide, molten zirconium oxide, mixtures of these oxides, silicon carbide, diamond, flint, graphite and emery.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-23 | 1982-04-24 | 1982-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-23 | 1986-04-24 | 1986-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-23 | 1990-04-24 | 1990-10-24 | $7700.00 | Window Closed / Lapsed |