Robert L Hart

US Patent:

6496733, Dec 17, 2002

Filed:

Sep 20, 2001

Appl. No.:

09/957330

Inventors:

Farhad Zarinetchi - Chelmsford MA
Robert M. Hart - Arlington MA
Michael G. Verga - Newton MA
Stephen J. Keville - Harvard MA

Assignee:

Abiomed, Inc. - Danver MA

International Classification:

A61N 1375

US Classification:

607 36, 607 61, 607 33

Abstract:

The invention provides a transcutaneous energy transfer device having an external primary coil and an implanted secondary coil inductively coupled to the primary coil, electronic components subcutaneously mounted within the secondary coil and a mechanism which reduces inductive heating of such components by the magnetic field of the secondary coil. For one embodiment of the invention, the mechanism for reducing inductive heating includes a cage formed of a high magnetic permeability material in which the electronic components are mounted, which cage guides the flux around the components to prevent heating thereof. For an alternative embodiment of the invention, a secondary coil has an outer winding and either a counter-wound inner winding or an inner winding in the magnetic field of the outer winding. For either arrangement of the inner coil, the inner coil generates a magnetic field substantially canceling the magnetic field of the outer coil in the area in which the electronic components are mounted.

US Patent:

20020038138, Mar 28, 2002

Filed:

Sep 20, 2001

Appl. No.:

09/957254

Inventors:

Farhad Zarinetchi - Bedford MA, US
Robert Hart - Arlington MA, US
Michael Verga - Newton MA, US
Stephen Keville - Harvard MA, US

International Classification:

A61N001/08

US Classification:

607/061000

Abstract:

The invention provides a transcutaneous energy transfer device having an external primary coil and an implanted secondary coil inductively coupled to the primary coil, electronic components subcutaneously mounted within the secondary coil and a mechanism which reduces inductive heating of such components by the magnetic field of the secondary coil. For one embodiment of the invention, the mechanism for reducing inductive heating includes a cage formed of a high magnetic permeability material in which the electronic components are mounted, which cage guides the flux around the components to prevent heating thereof. For an alternative embodiment of the invention, a secondary coil has an outer winding and either a counter-wound inner winding or an inner winding in the magnetic field of the outer winding. For either arrangement of the inner coil, the inner coil generates a magnetic field substantially canceling the magnetic field of the outer coil in the area in which the electronic components are mounted.

US Patent:

20020087204, Jul 4, 2002

Filed:

Jan 4, 2001

Appl. No.:

09/754835

Inventors:

Robert Kung - Andover MA, US
Robert Hart - Arlington MA, US
Farhad Zarinetchi - Chelmsford MA, US

International Classification:

A61N001/08

US Classification:

607/061000

Abstract:

A substantially flexible primary coil for use in a transcutaneous energy transfer (TET) device. When in use, the primary coil conforms to the contours of a patient's body, and, more particularly, to the shape of the skin under which a secondary coil of the TET is implanted. The shape of the primary coil adjusts with short term and long term changes in the contour of the patient's skin, enabling the primary coil to maintain a desired relative position with the implanted secondary coil as the patient changes position, posture or orientation, as well as over time as the patient loses or gains weight. The primary coil includes a shape-retaining base ring defining a primary plane. The base ring is firm, yet is able to conform to the contours of the substrate upon which it is placed. Attached to the base ring is a conducting element such as flexible wire which is coiled to form a plurality of nearly concentric windings. The windings are able to move at any angle, including transverse, to the primary plane so as to adopt the shape of the skin against which it is placed. In this way, the primary coil can be placed on any irregular surface and take the shape of the irregularities. A binding element is bound to the plurality of windings so that the near concentricity of the windings is maintained when the windings move.

US Patent:

20030113208, Jun 19, 2003

Filed:

Dec 17, 2001

Appl. No.:

10/024454

Inventors:

Robert Hart - Arlington MA, US
Robert Kung - Andover MA, US
Christopher Petroff - Croton MA, US
Farhad Zarinetchi - Chelmsford MA, US

International Classification:

F04D007/02
F01D001/02

US Classification:

415/206000, 415/900000, 416/185000

Abstract:

A rotary blood pump comprises a housing and a rotor. The housing includes a blood inlet, a blood outlet, a blood flow conduit disposed between the blood inlet and the blood outlet, and a rotary bearing assembly disposed within and fixed to the housing. The rotor is rotatably disposed within the housing and includes one or more impellor blades disposed within the blood flow conduit for pumping blood through the conduit, and a shaft affixed to and rotating with the rotor. The shaft rotatably engages the bearing assembly to define an intersection between the rotor and the housing and to provide relative rotation between the rotor and the housing. In addition, the shaft further defines an axis of rotation for the rotor. In the rotary pump of the invention, at least one of the rotor and the housing defines a swirl region proximate to the intersection between the rotor and the housing. The swirl region includes a curved surface adapted to cause blood being pumped through the blood flow conduit to swirl about an axis that is transverse to and spaced apart from the axis of rotation of the rotor. This swirl washes the intersection between the housing and the rotor, and further provides blood flow in a region that would otherwise have low flow.

US Patent:

20070073393, Mar 29, 2007

Filed:

Sep 26, 2005

Appl. No.:

11/235691

Inventors:

Robert Kung - Andover MA, US
Farhad Zarinetchi - Chelmsford MA, US
Robert Hart - Arlington MA, US

Assignee:

ABIOMED, Inc. - Danvers MA

International Classification:

A61M 1/12
F04B 49/00

US Classification:

623003130, 417043000, 623003280, 600017000

Abstract:

At least one aspect is directed to a totally artificial heart, and at least another aspect is directed to a method of controlling blood flow in a patient. The totally artificial heart may include a first rotary pump having an input to receive blood and an output to provide blood to a patient's lungs, a second rotary pump having an input to receive blood and an output to provide blood to the patient's body, a first sensor associated with the first rotary pump, a second sensor associated with the second rotary pump, and a control system coupled to the first sensor, the second sensor, the first rotary pump and the second rotary pump and configured to control characteristics of the first rotary pump and the second rotary pump based on signals received from at least one of the first sensor and the second sensor such that an average flow of blood through the second rotary pump is greater than an average flow of blood through the first rotary pump

US Patent:

60710934, Jun 6, 2000

Filed:

Oct 18, 1996

Appl. No.:

8/733981

Inventors:

Robert M. Hart - Arlington MA

Assignee:

Abiomed, Inc.
Danvers, Inc.

International Classification:

F04B 1704

US Classification:

4174242

Abstract:

A magnetically operated blood pump includes a rotor with an impeller that rotates within a housing, and the housing fastens to a driver that preferably electromagnetically controls the speed and disposition of the impeller in response to sensed conditions. The impeller and housing constitute a disposable assembly in which permanent magnets embedded in the impeller stabilize its position to maintain pumping tolerances in at least one dimension, and also couple to external fields to rotate the impeller. In one embodiment concentric arrangements of cylinder magnets passively maintain radial centering, while coils in the driver are actuated to simultaneously produce a rotational torque and to correct axial or tilt displacements. In a preferred embodiment of this type, sensors around the periphery detect axial displacement and/or tilt as the impeller turns, while the drive circuit responds to the sensor signal to produce compensating phase changes in the coil drive signals. The drive coils are disposed in a common plane and are symmetrically spaced about the central axis, and the phase changes in their drive signals result in a compensating axial force, which may be different in each of the coils to correct tilt.

US Patent:

63244306, Nov 27, 2001

Filed:

Jul 6, 1998

Appl. No.:

9/110608

Inventors:

Farhad Zarinetchi - Chelmsford MA
Stephen J. Keville - Harvard MA
Robert M. Hart - Arlington MA

Assignee:

Abiomed, Inc. - Danvers MA

International Classification:

H02J 1700

US Classification:

607 61

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.

US Patent:

63244314, Nov 27, 2001

Filed:

Jul 2, 1999

Appl. No.:

9/346833

Inventors:

Farhad Zarinetchi - Chelmsford MA
Robert M. Hart - Arlington MA
Michael G. Verga - Newton MA
Stephen J. Keville - Harvard MA

Assignee:

Abiomed, Inc. - Danvers MA

International Classification:

A61N 1375

US Classification:

607 61

Abstract:

The invention provides a transcutaneous energy transfer device having an external primary coil and an implanted secondary coil inductively coupled to the primary coil, electronic components subcutaneously mounted within the secondary coil and a mechanism which reduces inductive heating of such components by the magnetic field of the secondary coil. For one embodiment of the invention, the mechanism for reducing inductive heating includes a cage formed of a high magnetic permeability material in which the electronic components are mounted, which cage guides the flux around the components to prevent heating thereof. For an alternative embodiment of the invention, a secondary coil has an outer winding and either a counter-wound inner winding or an inner winding in the magnetic field of the outer winding. For either arrangement of the inner coil, the inner coil generates a magnetic field substantially canceling the magnetic field of the outer coil in the area in which the electronic components are mounted.