US6324430B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic shield for primary coil of transcutaneous energy transfer device
Assignee: Abiomed Inc
•
Filing: 1998-07-06
•
Granted: 2001-11-27
•
Expires: 2018-07-06
Abstract
Abstract A transcutaneous energy transfer device is provided which has a magnetic shield covering the primary winding of the device to reduce sensitivity of the device to conducting objects in the vicinity of the coils and to increase the percentage of magnetic field generated by the primary coil which reaches the secondary coil. This shield is preferably larger than the primary coil in all dimensions and is either formed of a high permeability flexible material, for example a low loss magnetic material in a flexible polymer matrix, with perforations formed in the material sufficient to permit ventilation of the patient's skin situated under the shield, or the shield may be formed of segments of very high permeability material connected by a flexible, porous mesh material.
Inventors
- 👤 Farhad Zarinetchi
- 👤 Stephen J. Keville
- 👤 Robert M. Hart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:07
CPC Classifications
A; A61; A61N; A61N1/00; A61N1/18; A61N1/32; A61N1/36; A61N1/372; A61N1/378; A61N1/3787; H; H01; H01F; H01F27/00; H01F27/34; H01F27/36; H01F27/366; H01F38/00; H01F38/14
Claims Analysis
Total Claims: 56
Claim 1
Independent Claim
68 words
A transcutaneous energy transfer device comprising: an external primary coil to which energy to be transferred is applied; an implanted secondary coil configured to be inductively coupled to said primary coil and connected to apply energy to a subcutaneous utilization device; and a magnetic shield covering a side of said primary coil opposite said secondary coil, wherein said magnetic shield has a plurality of ventilation perforations formed therein.
Claim 2
Dependent Claim
68 words
A transcutaneous energy transfer device comprising: an external primary coil to which energy to be transferred is applied; an implanted secondary coil configured to be inductively coupled to said primary coil and connected to apply energy to a subcutaneous utilization device; and a magnetic shield covering a side of said primary coil opposite said secondary coil, wherein said magnetic shield has a plurality of ventilation perforations formed therein.
Claim 3
Dependent Claim
16 words
A device as claimed in claim 1 wherein said shield is larger than said primary coil.
Claim 4
Dependent Claim
35 words
A device as claimed in claim 2 wherein said primary coil has a selected shape and size, and wherein said shield is of substantially the same shape as said primary coil, but of greater size.
Claim 5
Dependent Claim
41 words
A device as claimed in claim 3 wherein said primary coil has dimensions x i in direction i, wherein the shield has a thickness t and wherein the dimensions of the shield in direction i is X i ≧x i +2t.
Claim 6
Dependent Claim
35 words
A device as claimed in claim 3 wherein said primary coil has a generally circular shape with a diameter d, and wherein said shield has a generally circular shape with a diameter D, where D>d.
Claim 7
Dependent Claim
17 words
A device as claimed in claim 5 wherein said shield has a thickness t, and wherein D≧d+2t.
Claim 8
Dependent Claim
35 words
A device as claimed in claim 5 wherein the shield is formed of a material having a magnetic permeability relative to free space (μ r ) and has a thickness (t), where t>>D/μ r .
Claim 9
Dependent Claim
40 words
A device as claimed in claim 1 wherein the shield is formed of a material having a magnetic permeability relative to free space (μ r ), has a major dimension X, and has a thickness (t) where t>>X/μ r .
Claim 10
Dependent Claim
18 words
A device as claimed in claim 1 wherein said perforations are formed parallel to the magnetic field direction.
Claim 11
Dependent Claim
24 words
A device as claimed in claim 9 wherein said primary coil is substantially circular, and wherein said perforations are a plurality of radial slots.
Claim 12
Dependent Claim
21 words
A device as claimed in claim 1 wherein said perforations cover approximately 25% to 75% of the area of the shield.
Claim 13
Dependent Claim
19 words
A device as claimed in claim 11 wherein said perforations cover approximately 50% of the area of the shield.
Claim 14
Dependent Claim
25 words
A device as claimed in claim 11 wherein all dimensions for the perforations are less than the dimensions of the smallest coil in the device.
Claim 15
Dependent Claim
91 words
A device as claimed in claim 1 wherein said primary coil has a generally circular shape with a diameter d, and wherein said shield has a generally circular shape with a diameter D, a thickness (t) and is formed of a material having a magnetic permeability relative to free space (μ r ), wherein the perforations result in a reduction μ r for the shield which is roughly proportional to the percentage of perforation area, and wherein the shield thickness is increased so as to maintain the relationship t>>D/μ r .
Claim 16
Dependent Claim
26 words
A device as claimed in claim 1 wherein said shield is flexible so as to be able to conform to the contours of a patient's body.
Claim 17
Dependent Claim
23 words
A device as claimed in claim 15 wherein said shield is formed of a low loss magnetic material in a flexible polymer matrix.
Claim 18
Dependent Claim
20 words
A device as claimed in claim 16 wherein said shield is formed of a ferrite powder in a silicone rubber.
Claim 19
Dependent Claim
29 words
A device as claimed in claim 15 wherein said shield is formed of a plurality of segments of a very high permeability material connected by a porous, flexible material.
Claim 20
Dependent Claim
63 words
A device as claimed in claim 18 wherein spacings between adjacent segments in a direction substantially parallel to the magnetic field direction of the primary coil is less than the dimensions of the smallest coil in the device, and spacing between adjacent segments in a direction substantially perpendicular to the magnetic field direction is much less than the spacing in said parallel direction.
Claim 21
Dependent Claim
19 words
A device as claimed in claim 18 wherein said segments cover approximately 25% to 75% of said shield area.
Claim 22
Dependent Claim
51 words
A device as claimed in claim 1 wherein said primary coil generates a magnetic field which is directed both toward and away from said secondary coil and wherein said shield is dimensioned and is formed of a material which reflects most of the magnetic field directed thereto toward said secondary coil.
Claim 23
Dependent Claim
75 words
A transcutaneous energy transfer device comprising: an external primary coil to which energy to be transferred is applied; an implanted secondary coil configured to be inductively coupled to said primary coil and connected to apply energy to a subcutaneous utilization device; and a magnetic shield adjacent a side of said primary winding opposite said secondary coil, wherein said shield is flexible so as to be able to conform to the contours of a patient's body.
Claim 24
Dependent Claim
75 words
A transcutaneous energy transfer device comprising: an external primary coil to which energy to be transferred is applied; an implanted secondary coil configured to be inductively coupled to said primary coil and connected to apply energy to a subcutaneous utilization device; and a magnetic shield adjacent a side of said primary winding opposite said secondary coil, wherein said shield is flexible so as to be able to conform to the contours of a patient's body.
Claim 25
Dependent Claim
23 words
A device as claimed in claim 22 wherein said shield is formed of a low loss magnetic material in a flexible polymer matrix.
Claim 26
Dependent Claim
20 words
A device as claimed in claim 23 wherein said shield is formed of a ferrite powder in a silicone rubber.
Claim 27
Dependent Claim
29 words
A device as claimed in claim 22 wherein said shield is formed of a plurality of segments of a very high permeability material connected by a porous, flexible material.
Claim 28
Dependent Claim
63 words
A device as claimed in claim 25 wherein spacings between adjacent segments in a direction substantially parallel to the magnetic field direction of the primary coil is less than the dimensions of the smallest coil in the device, and spacing between adjacent segments in a direction substantially perpendicular to the magnetic field direction is much less than the spacing in said parallel direction.
Claim 29
Dependent Claim
19 words
A device as claimed in claim 25 wherein said segments cover approximately 25% to 75% of said shield area.
Claim 30
Dependent Claim
16 words
A device as claimed in claim 22 wherein said shield is larger than said primary coil.
Claim 31
Dependent Claim
35 words
A device as claimed in claim 28 wherein said primary coil has a selected shape and size, and wherein said shield is of substantially the same shape as said primary coil, but of greater size.
Claim 32
Dependent Claim
35 words
A device as claimed in claim 29 wherein said primary coil has a generally circular shape with a diameter d, and wherein said shield has a generally circular shape with a diameter D, where D>d.
Claim 33
Dependent Claim
17 words
A device as claimed in claim 30 wherein said shield has a thickness t, and wherein D≧d+2t.
Claim 34
Dependent Claim
35 words
A device as claimed in claim 30 wherein the shield is formed of a material having a magnetic permeability relative to free space (μ r ) and has a thickness (t), where t>>D/μ r .
Claim 35
Dependent Claim
40 words
A device as claimed in claim 22 wherein the shield is formed of a material having a magnetic permeability relative to free space (μ r ), has a major dimension X, and has a thickness (t) where t>>X/μ r .
Claim 36
Dependent Claim
51 words
A device as claimed in claim 22 wherein said primary coil generates a magnetic field which is directed both toward and away from said secondary coil and wherein said shield is dimensioned and is formed of a material which reflects most of the magnetic field directed thereto toward said secondary coil.
Claim 37
Dependent Claim
75 words
A transcutaneous energy transfer device comprising: an external primary coil to which energy to be transferred is applied; an implanted secondary coil configured to be inductively coupled to said primary coil and connected to apply energy to a subcutaneous utilization device; and a magnetic shield covering a side of said primary winding opposite said secondary coil, wherein said shield is a flexible shield formed of a low loss magnetic material in a flexible polymer matrix.
Claim 38
Dependent Claim
75 words
A transcutaneous energy transfer device comprising: an external primary coil to which energy to be transferred is applied; an implanted secondary coil configured to be inductively coupled to said primary coil and connected to apply energy to a subcutaneous utilization device; and a magnetic shield covering a side of said primary winding opposite said secondary coil, wherein said shield is a flexible shield formed of a low loss magnetic material in a flexible polymer matrix.
Claim 39
Dependent Claim
16 words
A device as claimed in claim 35 wherein said shield is larger than said primary coil.
Claim 40
Dependent Claim
35 words
A device as claimed in claim 35 wherein said primary coil has a selected shape and size, and wherein said shield is of substantially the same shape as said primary coil, but of greater size.
Claim 41
Dependent Claim
40 words
A device as claimed in claim 37 wherein said primary coil has dimensions x i in direction i, wherein the shield has a thickness t and wherein the dimensions of the shield in direction i is X i≧x i +2t.
Claim 42
Dependent Claim
35 words
A device as claimed in claim 37 wherein said primary coil has a generally circular shape with a diameter d, and wherein said shield has a generally circular shape with a diameter D, where D>d.
Claim 43
Dependent Claim
18 words
A device as claimed in claim 35 wherein said shield has a plurality of ventilation perforations formed therein.
Claim 44
Dependent Claim
18 words
A device as claimed in claim 40 wherein said perforations are formed parallel to the magnetic field direction.
Claim 45
Dependent Claim
24 words
A device as claimed in claim 35 wherein said low loss magnetic material is ferrite powder and said flexible polymer matrix is silicone rubber.
Claim 46
Dependent Claim
29 words
A device as claimed in claim 35 wherein said shield is formed of a plurality of segments of a very high permeability material connected by a porous, flexible material.
Claim 47
Dependent Claim
75 words
A transcutaneous energy transfer device comprising: an external primary coil to which energy to be transferred is applied; an implanted secondary coil configured to be inductively coupled to said primary coil and connected to apply energy to a subcutaneous utilization device; and a flexible, conforming magnetic shield covering a side of said primary winding opposite said secondary coil, wherein said shield is formed of a plurality of individual segments connected by a porous, flexible material.
Claim 48
Dependent Claim
75 words
A transcutaneous energy transfer device comprising: an external primary coil to which energy to be transferred is applied; an implanted secondary coil configured to be inductively coupled to said primary coil and connected to apply energy to a subcutaneous utilization device; and a flexible, conforming magnetic shield covering a side of said primary winding opposite said secondary coil, wherein said shield is formed of a plurality of individual segments connected by a porous, flexible material.
Claim 49
Dependent Claim
20 words
A device as claimed in claim 44 wherein said plurality of segments comprise segments of a very high permeability material.
Claim 50
Dependent Claim
63 words
A device as claimed in claim 44 wherein spacings between adjacent segments in a direction substantially parallel to the magnetic field direction of the primary coil is less than the dimensions of the smallest coil in the device, and spacing between adjacent segments in a direction substantially perpendicular to the magnetic field direction is much less than the spacing in said parallel direction.
Claim 51
Dependent Claim
48 words
A device as claimed in claim 44 wherein said shield includes a first side facing said primary coil and a second surface opposite said first side, said first and second sides having a surface area, and wherein said segments cover approximately 25% to 75% of said surface area.
Claim 52
Dependent Claim
51 words
A device as claimed in claim 44 wherein said primary coil generates a magnetic field which is directed both toward and away from said secondary coil and wherein said shield is dimensioned and is formed of a material which reflects most of the magnetic field directed thereto toward said secondary coil.
Claim 53
Dependent Claim
16 words
A device as claimed in claim 44 wherein said shield is larger than said primary coil.
Claim 54
Dependent Claim
41 words
A device as claimed in claim 44 wherein said primary coil has dimensions x i in direction i, wherein the shield has a thickness t and wherein the dimensions of the shield in direction i is X i ≧x i +2t.
Claim 55
Dependent Claim
35 words
A device as claimed in claim 44 wherein said primary coil has a generally circular shape with a diameter d, and wherein said shield has a generally circular shape with a diameter D, where D>d.
Claim 56
Dependent Claim
17 words
A device as claimed in claim 51 wherein said shield has a thickness t, and wherein D≧d+2t.
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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) | 2004-11-26 | 2005-05-28 | 2005-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-11-26 | 2009-05-28 | 2009-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-11-26 | 2013-05-28 | 2013-11-27 | $7700.00 | Window Closed / Lapsed |