EP0240674A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Pump
Assignee: Ebara Corp
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Filing: 1987-02-13
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Granted: —
•
Expires: 2007-02-13
Abstract
Abstract A pump including an impeller having a magnet or a second conductor therein, the impeller being adapted to be directly rotated by virtue of magnetic fields of stator coils. The impeller is rotated within a casing in close proximity thereto via ceramic bearing members, one bearing member having spiral grooves on its slide surface. The ceramic bearing members constitute a dynamic pressure bearing means.
Inventors
- 👤 Shotaro Mizobuchi
- 👤 Yoshikazu Kimura
- 👤 Katsumi Sasaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 15:47
CPC Classifications
F; F04; F04D; F04D13/00; F04D13/02; F04D13/06; F04D29/00; F04D29/04; F04D29/046; F04D29/0465; F04D13/0666; F04D29/041; F04D29/0413; F04D29/0467; F16; F16C; F16C17/00; F16C17/04; F16C17/045; F16C33/00; F16C33/02; F16C33/04; F16C33/043; F16C33/06; F16C33/10; F16C33/1025; F16C33/106; F16C33/1065; F16C2360/00; F16C2360/44
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
145 words
A pump comprising: a casing having an inlet and an outlet; an impeller having a rotary axis, arranged within the casing; driving force receiving means disposed to the impeller; stator coils arranged within the casing, which impart the driving force to the driving force receiving means; separating means mounted to the casing for separating the impeller from the stator coils; a first element secured to one end of the impeller in a plane perpendicular to the rotary axis of the impeller; and a second stationary element arranged in the casing opposing to the first element in parallel therewith, the first and the second elements being adapted to abut against each other at their flat surfaces, one of the opposed flat surfaces of the first and the second elements having a spiral groove pattern, the first and the second elements being made of a ceramic material.
Claim 2
Dependent Claim
145 words
A pump comprising: a casing having an inlet and an outlet; an impeller having a rotary axis, arranged within the casing; driving force receiving means disposed to the impeller; stator coils arranged within the casing, which impart the driving force to the driving force receiving means; separating means mounted to the casing for separating the impeller from the stator coils; a first element secured to one end of the impeller in a plane perpendicular to the rotary axis of the impeller; and a second stationary element arranged in the casing opposing to the first element in parallel therewith, the first and the second elements being adapted to abut against each other at their flat surfaces, one of the opposed flat surfaces of the first and the second elements having a spiral groove pattern, the first and the second elements being made of a ceramic material.
Claim 3
Dependent Claim
26 words
A pump as claimed in claim l, wherein the ceramic material is a sintered body selected from the group consisting of α-SiC, β-SiC, Al₂O₃ and Si₃N₄.
Claim 4
Dependent Claim
18 words
A pump as claimed in claim l, wherein the spiral groove pattern is formed by a shot-blasting process.
Claim 5
Dependent Claim
50 words
A pump as claimed in claim l, wherein the first element is secured to the central portion of the rear end of the impeller, the rear end of the impeller facing to the separating means, and the first element is provided with the spiral groove pattern on its flat surface.
Claim 6
Dependent Claim
50 words
A pump as claimed in claim l, wherein the first element is secured to the central portion of the front end of the impeller, the rear end of the impeller facing to the separating means, and the second element is provided with the spiral groove pattern on its flat surface.
Claim 7
Dependent Claim
39 words
A pump as claimed in claim 4, wherein the impeller is provided with a central through-hole along its rotary axis, and the first element is an annular plate which is secured to the impeller coaxially with the central throughhole.
Claim 8
Dependent Claim
26 words
A pump as claimed in claim 4, wherein the first element is a circular plate which is secured to the impeller coaxially with its rotary axis.
Claim 9
Dependent Claim
45 words
A pump as claimed in claim 5, wherein the first element is an annular plate, and the second element is an annular plate of the same form as that of the second element, the second element being mounted to the inlet portion of the casing.
Claim 10
Dependent Claim
67 words
A pump as claimed in claim 8, wherein the pump further comprises a third element secured to the central portion of the rear end of the impeller in a plane perpendicular to the rotary axis of the impeller, and a fourth statationary element arranged in the casing opposing to the third element in parallel therewith, the third and the fourth elements being made of a ceramic material.
Claim 11
Dependent Claim
35 words
l0. A pump as claimed in claim 6, wherein the driving force receiving means is an annular permanent magnet which is arranged in the outer rear end of the impeller and surrounds the first element.
Claim 12
Dependent Claim
34 words
A pump as claimed in claim 7, wherein the driving force receiving means is an annular secondary conductor which is arranged in the outer rear end of the impeller and surrounds the first element.
Claim 13
Dependent Claim
34 words
A pump as claimed in claim 9, wherein the driving force receiving means is an annular permanent magnet which is arranged in the outer rear end of the impeller and surrounds the third element.
Claim 14
Dependent Claim
43 words
A pump as claimed in claim 9, wherein the third and the fourth element are each provided with grooves on their opposed surfaces along the rotary axis of the impeller, and a small ball is arranged in a space composed of the grooves.
Claim 15
Dependent Claim
36 words
A pump as claimed in claim l0, wherein the annular permanent magnet is covered by an annular ceramic thin plate over its outer surface and is attached by an annular iron plate over its back surface.
Claim 16
Dependent Claim
36 words
A pump as claimed in claim l2, wherein the annular permanent magnet is covered by an annular ceramic thin plate over its outer surface and is attached by an annular iron plate over its back surface.
Claim 17
Dependent Claim
24 words
A pump as claimed in claim ll, wherein the annular secondary conductor is covered by an annular ceramic thin plate over its outer surface.
Claim 18
Dependent Claim
39 words
A pump as claimed in claim l3, wherein the diameter of the small ball is larger than that of the space so that the opposed surfaces of the third and the fourth elements may be away from each other.
Claim 19
Dependent Claim
56 words
A pump as claimed in claim l3, wherein the diameter of the small ball is smaller than that of the space, the third and the fourth elements being adapted to abut against each other at their flat surfaces, one of the opposed flat surfaces of the third and the fourth elements having a spiral groove pattern.
Claim 20
Dependent Claim
57 words
A pump as claimed in claim l4, wherein the second element is a ceramic thin plate which covers the stator coils on one end opposite to the impeller through a synthetic resin and is mounted to the casing so as to seal the stator coils from the liquid and to separate the stator coils from the impeller.
Claim 21
Dependent Claim
64 words
A pump as claimed in claim l5, wherein the stator coils are covered on one end opposite to the impeller by a ceramic thin plate, and the fourth element is mounted to the casing via a synthetic resin, the ceramic thin plate, the synthetic resin and the fourth element sealing the stator coils from the liquid and separating the stator coils from the impeller.
Claim 22
Dependent Claim
65 words
2l. A pump as claimed in claim l6, wherein the stator coils are covered on one end opposite to the impeller by a ceramic thin plate, and the second element is mounted to the casing via a synthetic resin, the ceramic thin plate, the synthetic resin and the second element sealing the stator coils from the liquid and separating the stator coils from the impeller.
References Cited (Backward Citations)
No citation records indexed.
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