Patent US5070658A successfully refreshed from Google Patents.
US5070658A
Expired / Lapsed
US
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Ceramic articles, and a process for the production thereof
Assignee: Ceramtec GmbH
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Filing: 1988-03-30
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Granted: 1991-12-10
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Expires: 2008-03-30
Abstract
Abstract A ceramic sealing component for a machine which is in frictional contact and has at least one non-reflective sliding and sealing face of a mean roughness (Ra) greater than 0.1 and a minimum of 0.8 μm is described. A component of this type can be produced by subjecting a green ceramic article to shaping, sintering, processing by face-grinding or round-grounding, optionally washing and then abrasive-polishing in the presence of an aqueous phase until the mean roughness desired for the machine component is reached.
Inventors
- 👤 Walter Rajner
- 👤 Klaus Russner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:57
CPC Classifications
B; B24; B24B; B24B31/00
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
113 words
A process for the production of ceramic sealing components for a machine, the components being in frictional contact and having at least one planar or curved sliding and sealing face, comprising the steps of shaping green ceramic articles, sintering, grinding and subsequently smoothing the sliding and sealing faces formed, wherein the articles are smoothed by abrasion with each other in the presence of an aqueous phase, without using scouring elements, until a mean roughness of greater than 0.1 and not more than 0.8 μm is reached, the articles used being shaped in such a way that the sliding and sealing faces of the articles come in contact with the other articles during smoothing.
Claim 2
Dependent Claim
113 words
A process for the production of ceramic sealing components for a machine, the components being in frictional contact and having at least one planar or curved sliding and sealing face, comprising the steps of shaping green ceramic articles, sintering, grinding and subsequently smoothing the sliding and sealing faces formed, wherein the articles are smoothed by abrasion with each other in the presence of an aqueous phase, without using scouring elements, until a mean roughness of greater than 0.1 and not more than 0.8 μm is reached, the articles used being shaped in such a way that the sliding and sealing faces of the articles come in contact with the other articles during smoothing.
Claim 3
Dependent Claim
21 words
The process as claimed in claim 1, wherein the abrasive polishing takes place without prior washing of the ground ceramic articles.
Claim 4
Dependent Claim
111 words
A process for the production of a ceramic sealing component for a machine, the component being in frictional contact and having at least one planar or curved sliding and sealing face, comprising the steps of shaping a green ceramic article, sintering, grinding and subsequently smoothing the sliding and sealing face formed, wherein the article is smoothed in the presence of an aqueous phase containing scouring elements, but in the absence of finely divided abrasively acting substances until a mean roughness of greater than 0.1 and not more than 0.8 μm is reached, and wherein at least one surface of the article to be smoothed is in the interior of the article.
Claim 5
Dependent Claim
111 words
A process for the production of a ceramic sealing component for a machine, the component being in frictional contact and having at least one planar or curved sliding and sealing face, comprising the steps of shaping a green ceramic article, sintering, grinding and subsequently smoothing the sliding and sealing face formed, wherein the article is smoothed in the presence of an aqueous phase containing scouring elements, but in the absence of finely divided abrasively acting substances until a mean roughness of greater than 0.1 and not more than 0.8 μm is reached, and wherein at least one surface of the article to be smoothed is in the interior of the article.
Claim 6
Dependent Claim
17 words
The process as claimed in claim 1, wherein the water contains organic additives having a surface activity.
Claim 7
Dependent Claim
15 words
The process as claimed in claim 1, wherein the articles are aluminum oxide ceramic articles.
Claim 8
Dependent Claim
30 words
The process as claimed in claim 1, wherein the apparatus used for smoothing is filled to the extent of 10 to 90% by volume with ceramic articles to be smoothed.
Claim 9
Dependent Claim
21 words
The process as claimed in claim 1, wherein the sliding and sealing faces of sliding rings or regulating washers are smoothed.
Claim 10
Dependent Claim
66 words
An aluminum oxide sealing component for a machine which is free from ZrO 2 and HfO 2 , the component being in frictional contact and having at least one planar sliding and sealing face, wherein the sliding and sealing face has a mean roughness (Ra) of greater than 0.1 and not more than 0.8 μm, as well as an evenness of 0.3-1.2 pm, and is non-reflective.
Claim 11
Dependent Claim
66 words
An aluminum oxide sealing component for a machine which is free from ZrO 2 and HfO 2 , the component being in frictional contact and having at least one planar sliding and sealing face, wherein the sliding and sealing face has a mean roughness (Ra) of greater than 0.1 and not more than 0.8 μm, as well as an evenness of 0.3-1.2 pm, and is non-reflective.
Claim 12
Dependent Claim
24 words
A component as claimed in claim 8, wherein the evenness of the sliding and sealing face is in the range 0.3 to 0.8 μm.
Claim 13
Dependent Claim
74 words
A ceramic sealing component for a machine which does not contain ZrO 2 and HfO 2 , the component being in frictional contact and having at least one sliding and sealing face, wherein the component has a cylindrical peripheral surface which is designed as a sliding and sealing face, a roughness (Ra) of greater than 0.1 and not more than 0.8 μm, as well as a surface accuracy of 0.3-1.2 μm, and is nonreflective.
Claim 14
Dependent Claim
74 words
A ceramic sealing component for a machine which does not contain ZrO 2 and HfO 2 , the component being in frictional contact and having at least one sliding and sealing face, wherein the component has a cylindrical peripheral surface which is designed as a sliding and sealing face, a roughness (Ra) of greater than 0.1 and not more than 0.8 μm, as well as a surface accuracy of 0.3-1.2 μm, and is nonreflective.
Claim 15
Dependent Claim
23 words
A component as claimed in claim 10, form of a cylindrical tube whose peripheral surface is designed as a sliding and sealing face.
Claim 16
Dependent Claim
33 words
A component as claimed in claim 10, which has the shape of a hollow cylinder which is closed at one end and whose cylindrical surface is designed as a sliding and sealing face.
Claim 17
Dependent Claim
30 words
A component as claimed in claim 12, wherein the front face of the hollow cylinder, has a mean roughness (Ra) of greater than 0.1 and a maximum of 0.8 μm.
Claim 18
Dependent Claim
27 words
A component as claimed in claim 8, which has a disk shape and wherein at least one side of the disk has a sliding and sealing face.
Claim 19
Dependent Claim
18 words
A component as claimed in claim 14, wherein the disk has a thickness of 1 to 10 mm.
Claim 20
Dependent Claim
43 words
A component as claimed in claim 14, wherein the F 0 .5 :D ratio is 3 to 12, where F is the surface area of the disk, defined by the external dimensions of the disk, and D is the thickness of the disk.
Claim 21
Dependent Claim
21 words
A component as claimed in claim 14, wherein the two sides of the disk are connected by at least one channel.
Claim 22
Dependent Claim
29 words
A component as claimed in claim 17, wherein the sum of the cross-sections of the individual channels on each side is 5 to 45% of the disk surface area.
Claim 23
Dependent Claim
42 words
A component as claimed in claim 8, which has the shape of a short cylindrical tube, at least one ring-shaped front face being designed as a sliding and sealing face and the external diameter : tube thickness ratio being at least 2.6.
Claim 24
Dependent Claim
18 words
A component as claimed in claim 10, wherein the cylinder length : diameter ratio is at least 1.
Claim 25
Dependent Claim
19 words
A component as claimed in claim 8, which has an aluminum oxide content of greater than 80% by weight.
Claim 26
Dependent Claim
17 words
The process as claimed in claim 3, wherein the water contains organic additives having a surface activity.
Claim 27
Dependent Claim
15 words
The process as claimed in claim 3, wherein the articles are aluminum oxide ceramic articles.
Claim 28
Dependent Claim
31 words
The process as claimed in claim 3, wherein the apparatus used for abrasive polishing is filled to the extent of 10 to 90% by volume with ceramic articles to be smoothed.
Claim 29
Dependent Claim
21 words
The process as claimed in claim 3, wherein the sliding and sealing faces of sliding rings or regulating washers are smoothed.
Claim 30
Dependent Claim
18 words
A component as claimed in claim 14, wherein the F 0 .5 :D ratio is 5 to 9.
Claim 31
Dependent Claim
24 words
A process as claimed in claim 3, wherein the scouring elements are selected from the group consisting of spheres and rods of ceramic material.
Claim 32
Dependent Claim
37 words
A process as claimed in claim 27, wherein the scouring elements are selected from the group consisting of spheres having a diameter of 3 to 10 mm and rods having a length of 3 to 10 mm.
Claim 33
Dependent Claim
19 words
A process as claimed in claim 3, wherein the scouring elements range in size from 3 to 10 mm.
Claim 34
Dependent Claim
17 words
A process as claimed in claim 3, wherein the articles undergo tumbling movements during the smoothing step.
Claim 35
Dependent Claim
21 words
A process as claimed in claim 3, wherein the articles undergo short oscillating movements of high frequency during the smoothing step.
Claim 36
Dependent Claim
34 words
A process as claimed in claim 8, wherein the component has an aluminum oxide content of at least 96% and the aluminum oxide has a mean crystalline size which does not exceed 8 microns.
Claim 37
Dependent Claim
34 words
A process as claimed in claim 8, wherein the component has an aluminum oxide content of at least 98% and the aluminum oxide has a mean crystalline size which does not exceed 8 microns.
Claim 38
Dependent Claim
18 words
A process as claimed in claim 32, wherein the means surface roughness is between 0.1 to 0.3 microns.
Claim 39
Dependent Claim
24 words
A process as claimed in claim 27, wherein the scouring elements and the article to be smoothed are made of the same ceramic material.
References Cited (Backward Citations)
DE1291957B
Cited
US3745722A
Cited
US3965620A
Cited
US4420142A
Cited
JPS58192745A
Cited
JPS60177864A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-12-09 | 1995-06-10 | 1995-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-09 | 1999-06-10 | 1999-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-09 | 2003-06-10 | 2003-12-10 | $7700.00 | Window Closed / Lapsed |