US5280208A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite bearing structure
Assignee: Sumitomo Electric Industries Ltd
•
Filing: 1992-08-05
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Granted: 1994-01-18
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Expires: 2012-08-05
Abstract
Abstract A composite bearing structure can withstand high speed rotation has first, second and third bearing components. The first bearing component supports a radial impact force applied to a rotator during rotation, and is made of an inner ring (1) and an outer ring (2) of silicon nitride ceramic sintered bodies. The second bearing component supports an axial load applied to the rotator while maintaining a required clearance between itself and the rotator and is made of two permanent magnets (12, 13) positioned thrustdirectionally opposite to each other. The third bearing component maintains a radial rotational accuracy of the rotator, and is made of a radial dynamic pressure producing groove (5) provided on a cylindrical surface of the inner ring (1).
Inventors
- 👤 Osamu Komura
- 👤 Kenji Matsunuma
- 👤 Norio Yasuoka
- 👤 Matsuo Higuchi
- 👤 Masaya Miyake
- 👤 Tetsuya Katayama
- 👤 Akira Yamakawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:34
CPC Classifications
F; F16; F16C; F16C39/00; F16C39/06; F16C39/063; F16C17/00; F16C17/02; F16C17/026; F16C17/04; F16C17/045; F16C17/10; F16C17/102; F16C17/107; F16C32/00; F16C32/04; F16C32/0402; F16C32/0406; F16C32/0408; F16C32/0423; F16C32/0427; F16C32/0429; F16C32/0431; F16C33/00; F16C33/02; F16C33/04; F16C33/043; F16C33/06; F16C33/10; F16C33/1005; F16C33/101; F16C33/1015; F16C33/1025; F16C33/106; F16C33/107
Claims Analysis
Total Claims: 50
Claim 1
Independent Claim
171 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) comprising a silicon nitride ceramic sintered body for supporting a radial impact force applied to said rotator during rotation, said silicon nitride ceramic sintered body containing silicon nitride crystal grains having a linear density of at lest 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume and pores having a maximum diameter of 20 μm, said pores occupying 3 volume percent at the most, second dynamic gas pressure bearing means (6) for supporting by a gas pressure produced by rotation of said rotator an axial load applied to said rotator while maintaining an axial clearance between said second bearing means and said rotator; and third dynamic gas pressure bearing means (1, 2) for maintaining a radial clearance and rotational accuracy of said rotator, said dynamic gas pressure being produced by rotation of said rotator.
Claim 2
Dependent Claim
171 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) comprising a silicon nitride ceramic sintered body for supporting a radial impact force applied to said rotator during rotation, said silicon nitride ceramic sintered body containing silicon nitride crystal grains having a linear density of at lest 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume and pores having a maximum diameter of 20 μm, said pores occupying 3 volume percent at the most, second dynamic gas pressure bearing means (6) for supporting by a gas pressure produced by rotation of said rotator an axial load applied to said rotator while maintaining an axial clearance between said second bearing means and said rotator; and third dynamic gas pressure bearing means (1, 2) for maintaining a radial clearance and rotational accuracy of said rotator, said dynamic gas pressure being produced by rotation of said rotator.
Claim 3
Dependent Claim
40 words
The composite bearing structure of claim 1, wherein said second dynamic gas pressure bearing means comprises a rotating member (2) rotating with said rotator and a fixed member (3) opposed to said rotating member (2) for maintaining said axial clearance.
Claim 4
Dependent Claim
48 words
The composite bearing structure of claim 2, wherein said rotating member (2) and said fixed member (3) comprise ceramic sintered bodies and grooves (6) formed in either one of said rotating and fixed members for introducing a gas into said axial clearance for producing said dynamic gas pressure.
Claim 5
Dependent Claim
40 words
The composite bearing structure of claim 1, wherein said third dynamic gas pressure bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) opposed to said rotating member for radially maintaining said rotational accuracy.
Claim 6
Dependent Claim
62 words
The composite bearing structure in accordance with claim 4, wherein said rotating member (2) and said fixed member (1) comprise ceramic sintered bodies, and groove means (5) in either one of said rotating member (2) and said fixed member (1) for producing said dynamic gas pressure by introducing a gas into said radial clearance for maintaining said rotational accuracy of said rotator.
Claim 7
Dependent Claim
257 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force applied to said rotator during rotation; second dynamic gas pressure bearing means (6) for supporting by a gas pressure produced by rotation of said rotator an axial load applied to said rotator while maintaining an axial clearance between said second bearing means and said rotator; and third magnetic bearing means (7, 8, 9, 10; 8, 10, 11; 7, 8, 14, 15) for maintaining a radial clearance and a rotational accuracy of said rotator by magnetic attraction or repulsion while maintaining said radial clearance between said third bearing means and said rotator, wherein said third magnetic bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) positioned opposite to said rotating member while maintaining said radial clearance, and wherein said rotating member (2) and said fixed member (1) include magnets (7, 8, 9, 10, 11, 14, 15) for generating magnetic attraction or repulsion in said radial clearance, said rotating and fixed members comprising ceramic sintered bodies and magnets, wherein said ceramic sintered body of said rotating member is positioned opposed to said ceramic sintered body of said fixed member while radially maintaining a first radial clearance, and wherein said magnet of said rotating member is opposed to said magnet of said fixed member while radially maintaining a second clearance wider than said first clearance.
Claim 8
Dependent Claim
257 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force applied to said rotator during rotation; second dynamic gas pressure bearing means (6) for supporting by a gas pressure produced by rotation of said rotator an axial load applied to said rotator while maintaining an axial clearance between said second bearing means and said rotator; and third magnetic bearing means (7, 8, 9, 10; 8, 10, 11; 7, 8, 14, 15) for maintaining a radial clearance and a rotational accuracy of said rotator by magnetic attraction or repulsion while maintaining said radial clearance between said third bearing means and said rotator, wherein said third magnetic bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) positioned opposite to said rotating member while maintaining said radial clearance, and wherein said rotating member (2) and said fixed member (1) include magnets (7, 8, 9, 10, 11, 14, 15) for generating magnetic attraction or repulsion in said radial clearance, said rotating and fixed members comprising ceramic sintered bodies and magnets, wherein said ceramic sintered body of said rotating member is positioned opposed to said ceramic sintered body of said fixed member while radially maintaining a first radial clearance, and wherein said magnet of said rotating member is opposed to said magnet of said fixed member while radially maintaining a second clearance wider than said first clearance.
Claim 9
Dependent Claim
40 words
The composite bearing structure of claim 6, wherein said second dynamic gas pressure bearing means includes a rotating member (2) rotating with said rotator and a fixed member (3) positioned opposed to said rotating member while maintaining said axial clearance.
Claim 10
Dependent Claim
50 words
The composite bearing structure of claim 7, wherein said rotating member (2) and said fixed member (3) include ceramic sintered bodies, and wherein grooves (6) are formed in either one of said rotating and fixed members for producing said dynamic gas pressure by introducing a gas into said axial clearance.
Claim 11
Dependent Claim
24 words
The composite bearing structure of claim 6, wherein said ceramic sintered body of said first bearing means includes a silicon nitride ceramic sintered body.
Claim 12
Dependent Claim
63 words
The composite bearing structure of claim 9, wherein said silicon nitride ceramic sintered body contains silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said process occupying 3 volume percent at the most.
Claim 13
Dependent Claim
214 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force applied to said rotator during rotation; second dynamic gas pressure bearing means (6) for supporting by a gas pressure produced by rotation of said rotator an axial load applied to said rotator while maintaining an axial clearance between said second bearing means and said rotator; and third magnetic bearing means (7, 8, 9, 10; 8, 10, 11; 7, 8, 14, 15) for maintaining a radial clearance and a rotational accuracy of said rotator by magnetic attraction or repulsion while maintaining said radial clearance between said third bearing means and said rotator, wherein said third magnetic bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) positioned opposite to said rotating member while maintaining said radial clearance, and wherein said rotating member (2) and said fixed member (1) include magnets (7, 8, 9, 10, 11, 14, 15) for generating magnetic attraction or repulsion in said radial clearance, and wherein said rotating and fixed members are formed by said ceramic sintered bodies, said magnets (11) being embedded in said ceramic sintered bodies.
Claim 14
Dependent Claim
214 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force applied to said rotator during rotation; second dynamic gas pressure bearing means (6) for supporting by a gas pressure produced by rotation of said rotator an axial load applied to said rotator while maintaining an axial clearance between said second bearing means and said rotator; and third magnetic bearing means (7, 8, 9, 10; 8, 10, 11; 7, 8, 14, 15) for maintaining a radial clearance and a rotational accuracy of said rotator by magnetic attraction or repulsion while maintaining said radial clearance between said third bearing means and said rotator, wherein said third magnetic bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) positioned opposite to said rotating member while maintaining said radial clearance, and wherein said rotating member (2) and said fixed member (1) include magnets (7, 8, 9, 10, 11, 14, 15) for generating magnetic attraction or repulsion in said radial clearance, and wherein said rotating and fixed members are formed by said ceramic sintered bodies, said magnets (11) being embedded in said ceramic sintered bodies.
Claim 15
Dependent Claim
41 words
The composite bearing structure in accordance with claim 11, wherein said dynamic pressure gas bearing means includes a rotating member (2) rotating with said rotator and a fixed member (3) being opposed to said rotating member while axially maintaining said clearance.
Claim 16
Dependent Claim
50 words
The composite bearing structure in accordance with claim 12, wherein said rotating member (2) and said fixed member (3) include ceramic sintered bodies, grooves (6) being formed in either one of said rotating and fixed members for introducing a gas into said clearance in order to produce said gas pressure.
Claim 17
Dependent Claim
24 words
The composite bearing structure of claim 11, wherein said ceramic sintered body of said first bearing means includes a silicon nitride ceramic sintered body.
Claim 18
Dependent Claim
64 words
The composite bearing structure of claim 14, wherein said silicon nitride ceramic sintered body contains silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said pores taking up 3 volume percent at the most.
Claim 19
Dependent Claim
163 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) comprising a silicon nitride ceramic sintered body for supporting a radial impact force applied to said rotator during rotation, said silicon nitride ceramic sintered body containing silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said process occupying 3 volume percent at the most, second dynamic gas pressure bearing means (6) for supporting by a gas pressure produced by rotation of said rotator an axial load applied to said rotator while maintaining an axial clearance between said second bearing means and said rotator, and third bearing means (1, 2) including a ceramic sintered body for maintaining a radial clearance and a rotational accuracy of said rotator.
Claim 20
Dependent Claim
163 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) comprising a silicon nitride ceramic sintered body for supporting a radial impact force applied to said rotator during rotation, said silicon nitride ceramic sintered body containing silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said process occupying 3 volume percent at the most, second dynamic gas pressure bearing means (6) for supporting by a gas pressure produced by rotation of said rotator an axial load applied to said rotator while maintaining an axial clearance between said second bearing means and said rotator, and third bearing means (1, 2) including a ceramic sintered body for maintaining a radial clearance and a rotational accuracy of said rotator.
Claim 21
Dependent Claim
41 words
The composite bearing structure in accordance with claim 16, wherein said dynamic pressure gas bearing means includes a rotating member (2) rotating with said rotator and a fixed member (3) being opposed to said rotating member while axially maintaining said clearance.
Claim 22
Dependent Claim
50 words
The composite bearing structure in accordance with claim 17, wherein said rotating member (2) and said fixed member (3) include ceramic sintered bodies, grooves (6) being formed in either one of said rotating and fixed members for introducing a gas into said clearance in order to produce said gas pressure.
Claim 23
Dependent Claim
167 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) comprising a silicon nitride ceramic sintered body for supporting a radial impact force applied to said rotator during rotation, said silicon nitride ceramic sintered body containing silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said process occupying 3 volume percent at the most, second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between magnetic bearing means and said rotator; and third dynamic gas pressure bearing means (1, 2) for maintaining a radial clearance and a rotational accuracy of said rotator by gas pressure produced by rotation of said rotator.
Claim 24
Dependent Claim
167 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) comprising a silicon nitride ceramic sintered body for supporting a radial impact force applied to said rotator during rotation, said silicon nitride ceramic sintered body containing silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said process occupying 3 volume percent at the most, second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between magnetic bearing means and said rotator; and third dynamic gas pressure bearing means (1, 2) for maintaining a radial clearance and a rotational accuracy of said rotator by gas pressure produced by rotation of said rotator.
Claim 25
Dependent Claim
39 words
The composite bearing structure of claim 19, wherein said second magnetic bearing means includes a rotating member (2, 12) rotating with said rotator and a fixed member (3, 13) opposed to said rotating member while maintaining said axial clearance.
Claim 26
Dependent Claim
37 words
The composite bearing structure of claim 20, wherein said rotating member (2, 12) and said fixed member (3, 13) includes magnets (12, 13, 10, 17, 15, 16) for generating magnetic attraction or repulsion in said axial clearance.
Claim 27
Dependent Claim
39 words
The composite bearing structure of claim 19, wherein said third dynamic gas pressure bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) opposed to said rotating member while maintaining said radial clearance.
Claim 28
Dependent Claim
62 words
The composite bearing structure in accordance with claim 22, wherein said rotating member (2) and said fixed member (1) comprise ceramic sintered bodies, and groove means (5) in either one of said rotating member (2) and said fixed member (1) for producing said dynamic gas pressure by introducing a gas into said radial clearance for maintaining said rotational accuracy of said rotator.
Claim 29
Dependent Claim
256 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force being applied to said rotator during rotation; second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between said second magnetic bearing means and said rotator; third magnetic bearing means (7, 8, 9, 10; 8, 10, 11; 7, 8, 14, 15) for maintaining a radial clearance and a rotational accuracy of said rotator through magnetic attraction or repulsion while maintaining said radial clearance between said third magnetic bearing means and said rotator, wherein said third magnetic bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) opposed to said rotating member while maintaining said radial clearance, and wherein said rotating member (2) and said fixed member (1) include magnets (7, 8, 9, 10, 11, 14, 15) for generating magnetic attraction or repulsion in said radial clearance, and wherein said rotating and fixed members are formed by said ceramic sintered bodies and said magnets, said ceramic sintered body of said rotating member being opposed to said ceramic sintered body of said fixed member, while maintaining a first radial clearance, and wherein said rotating magnet member being opposed to said fixed magnet member while maintaining a second radial clearance wider than said first radial clearance.
Claim 30
Dependent Claim
256 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force being applied to said rotator during rotation; second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between said second magnetic bearing means and said rotator; third magnetic bearing means (7, 8, 9, 10; 8, 10, 11; 7, 8, 14, 15) for maintaining a radial clearance and a rotational accuracy of said rotator through magnetic attraction or repulsion while maintaining said radial clearance between said third magnetic bearing means and said rotator, wherein said third magnetic bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) opposed to said rotating member while maintaining said radial clearance, and wherein said rotating member (2) and said fixed member (1) include magnets (7, 8, 9, 10, 11, 14, 15) for generating magnetic attraction or repulsion in said radial clearance, and wherein said rotating and fixed members are formed by said ceramic sintered bodies and said magnets, said ceramic sintered body of said rotating member being opposed to said ceramic sintered body of said fixed member, while maintaining a first radial clearance, and wherein said rotating magnet member being opposed to said fixed magnet member while maintaining a second radial clearance wider than said first radial clearance.
Claim 31
Dependent Claim
39 words
The composite bearing structure of claim 24, wherein said second magnetic bearing means includes a rotating member (2, 12) rotating with said rotator and a fixed member (3, 13) opposed to said rotating member while maintaining said axial clearance.
Claim 32
Dependent Claim
37 words
The composite bearing structure of claim 25, wherein said rotating member (2, 12) and said fixed member (3, 13) include magnets (12, 13, 10, 17, 15, 16) for generating magnetic attraction or repulsion in said axial clearance.
Claim 33
Dependent Claim
24 words
The composite bearing structure of claim 24, wherein said ceramic sintered body of said first bearing means includes a silicon nitride ceramic sintered body.
Claim 34
Dependent Claim
63 words
The composite bearing structure of claim 27, wherein said silicon nitride ceramic sintered body contains silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pore shaving a maximum diameter of 20 μm, said pores occupying 3 volume percent at the most.
Claim 35
Dependent Claim
215 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force being applied to said rotator during rotation; second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between said second magnetic bearing means and said rotator; and third magnetic bearing means (7, 8, 9, 10; 8, 10, 11; 7, 8, 14, 15) for maintaining a radial clearance and a rotational accuracy of said rotator by a magnetic attraction or repulsion while maintaining said radial clearance between said third magnetic bearing means and said rotator, wherein said third magnetic bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) opposed to said rotating member while radially maintaining said radial clearance, wherein said rotating member (2) and said fixed member (1) include magnets (7, 8, 9, 10, 11, 14, 15) for generating magnetic attraction or repulsion in said radial clearance, and wherein said rotating and fixed members are formed by said ceramic sintered bodies, said magnets (11) being embedded in said ceramic sintered bodies.
Claim 36
Dependent Claim
215 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force being applied to said rotator during rotation; second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between said second magnetic bearing means and said rotator; and third magnetic bearing means (7, 8, 9, 10; 8, 10, 11; 7, 8, 14, 15) for maintaining a radial clearance and a rotational accuracy of said rotator by a magnetic attraction or repulsion while maintaining said radial clearance between said third magnetic bearing means and said rotator, wherein said third magnetic bearing means includes a rotating member (2) rotating with said rotator and a fixed member (1) opposed to said rotating member while radially maintaining said radial clearance, wherein said rotating member (2) and said fixed member (1) include magnets (7, 8, 9, 10, 11, 14, 15) for generating magnetic attraction or repulsion in said radial clearance, and wherein said rotating and fixed members are formed by said ceramic sintered bodies, said magnets (11) being embedded in said ceramic sintered bodies.
Claim 37
Dependent Claim
39 words
The composite bearing structure of claim 29, wherein said second magnetic bearing means includes a rotating member (2, 12) rotating with said rotator and a fixed member (3, 13) opposed to said rotating member while maintaining said axial clearance.
Claim 38
Dependent Claim
37 words
The composite bearing structure of claim 30, wherein said rotating member (2, 12) and said fixed member (3, 13) include magnets (12, 13, 10, 17, 15, 16) for generating magnetic attraction or repulsion in said axial clearance.
Claim 39
Dependent Claim
24 words
The composite bearing structure of claim 29, wherein said ceramic sintered body of said first bearing means includes a silicon nitride ceramic sintered body.
Claim 40
Dependent Claim
63 words
The composite bearing structure of claim 32, wherein said silicon nitride ceramic sintered body contains silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said pores occupying 3 volume percent at the most.
Claim 41
Dependent Claim
168 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a silicon nitride ceramic sintered body for supporting a radial impact force applied to said rotator during rotation, said silicon nitride ceramic sintered body containing crystal grains having a linear density of at least 35 grains per 30 μlength, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said pores occupying 3 volume percent at the most, second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between said second magnetic bearing means and said rotator; and third being means (1, 2) including a ceramic sintered body for maintaining a radial rotational accuracy of said rotator, and a radial clearance between said third bearing means and said rotor.
Claim 42
Dependent Claim
168 words
A composite bearing structure for supporting a rotator carrying a load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a silicon nitride ceramic sintered body for supporting a radial impact force applied to said rotator during rotation, said silicon nitride ceramic sintered body containing crystal grains having a linear density of at least 35 grains per 30 μlength, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said pores occupying 3 volume percent at the most, second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between said second magnetic bearing means and said rotator; and third being means (1, 2) including a ceramic sintered body for maintaining a radial rotational accuracy of said rotator, and a radial clearance between said third bearing means and said rotor.
Claim 43
Dependent Claim
39 words
The composite bearing structure of claim 34, wherein said second magnetic bearing means includes a rotating member (2, 12) rotating with said rotator and a fixed member (3, 13) opposed to said rotating member while maintaining said axial clearance.
Claim 44
Dependent Claim
37 words
The composite bearing structure of claim 35, wherein said rotating member (2, 12) and said fixed member (3, 13) include magnets (12, 13, 10, 17, 15, 16) for generating magnetic attraction or repulsion in said axial clearance.
Claim 45
Dependent Claim
160 words
A composite bearing structure for supporting a rotator carrying a required load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force applied to said rotator during rotation; second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between said magnetic bearing means and said rotator; and third bearing means including a ceramic sintered body for maintaining a radial rotational accuracy of said rotator and for maintaining a radial clearance between said third bearing means and said rotator, and wherein said third bearing means including a rotating member rotating with said rotator and a fixed member opposed to said rotating member while maintaining said radial clearance and wherein said rotating and fixed members of said third bearing means are formed by ceramic sintered bodies.
Claim 46
Dependent Claim
160 words
A composite bearing structure for supporting a rotator carrying a required load for rotating at a high speed, said composite bearing structure comprising: first bearing means (1, 2) including a ceramic sintered body for supporting a radial impact force applied to said rotator during rotation; second magnetic bearing means (12, 13; 15, 16; 10, 17) for supporting by magnetic attraction or repulsion an axial load applied to said rotator while maintaining an axial clearance between said magnetic bearing means and said rotator; and third bearing means including a ceramic sintered body for maintaining a radial rotational accuracy of said rotator and for maintaining a radial clearance between said third bearing means and said rotator, and wherein said third bearing means including a rotating member rotating with said rotator and a fixed member opposed to said rotating member while maintaining said radial clearance and wherein said rotating and fixed members of said third bearing means are formed by ceramic sintered bodies.
Claim 47
Dependent Claim
39 words
The composite bearing structure of claim 37, wherein said second magnetic bearing means includes a rotating member (2, 12) rotating with said rotator and a fixed member (3, 13) opposed to said rotating member while maintaining said axial clearance.
Claim 48
Dependent Claim
37 words
The composite bearing structure of claim 38, wherein said rotating member (2, 12) and said fixed member (3, 13) include magnets (12, 13, 10, 17, 15, 16) for generating magnetic attraction or repulsion in said axial clearance.
Claim 49
Dependent Claim
24 words
The composite bearing structure of claim 37, wherein said ceramic sintered body of said first bearing means includes a silicon nitride ceramic sintered body.
Claim 50
Dependent Claim
63 words
The composite bearing structure of claim 40, wherein said silicon nitride ceramic sintered body contains silicon nitride crystal grains having a linear density of at least 35 grains per 30 μm length, a boundary phase volume ratio of not more than 15 percent by volume, and pores having a maximum diameter of 20 μm, said pores occupying 3 volume percent at the most.
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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) | 1997-01-17 | 1997-07-19 | 1998-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-01-17 | 2001-07-19 | 2002-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-01-17 | 2005-07-19 | 2006-01-18 | $7700.00 | Window Closed / Lapsed |