Back to results
US 6,093,001 AGranted
Rotary pump having a bearing which dissipates heat
AssigneeUniversity of Pittsburgh
InventorsGregory W. Burgreen, James F. Antaki
Life of this patent
Estimating the term…
Abstract
A rotary pump having a housing defining a flow path, a stator attached to the housing, a rotor which contacts the stator and rotates thereabout, a motor for rotating the rotor and semiconductor-based electronic components which draws the heat created by the frictional contact between the stator and rotor away from blood flowing through the housing. The rotary pump can be a centrifugal pump having a housing with a base plate, a rotor with rotor blades and a stator wherein the base plate and the rotor are shaped and proportioned such that blood is prevented from stagnating/collecting between the rotor blades and base plate.
Claims21
A blood pump for pumping blood that prevents coagulation of blood flowing through the pump by maintaining the blood flowing through the pump below a threshold temperature at which the blood coagulates, comprising:
- (a) a housing that has an inlet and an outlet;
- (b) a stator, disposed within and attached to the housing by a plurality of stator blades extending from the stator to the housing, a blood flow path being defined between the stator and the housing and between each of the stator blades,
- (c) a rotor, disposed within the housing between the inlet and the outlet, and having an end that is coupled to the stator by a mechanical bearing that generates heat during operation of the pump, the mechanical bearing comprising a first bearing gap, disposed between the mechanical bearing and the rotor, so that blood can flow through the first bearing gap and lubricate the bearing;
- (d) a mechanism that imparts rotational movement to the rotor;
- and
- (e) at least one electronic component, disposed within the stator proximal to the mechanical bearing, and wherein during operation of the pump the electronic component draws heat from (i) the rotor;
- (ii) the mechanical bearing, and (iii) the blood flowing proximal to the mechanical bearing and through the first bearing gap and the blood flowing proximal to the rotor, and transfers heat, via conductive heat transfer, to the stator and the housing, the stator and the housing transferring heat via advective convection to the blood flowing along the flow path and thereby maintaining the temperature of the blood below the threshold temperature and preventing coagulation of the blood.
4 more elements
A centrifugal rotary blood pump for pumping blood through a patient that maintains the blood flowing through the pump below a threshold temperature at which the blood coagulates, comprising:
- (a) a housing having an inlet, an outlet and a base plate;
- (b) a stator attached to the housing at the inlet by a plurality of stator blades;
- (c) a rotor rotatably connected to both the stator and the housing, the rotor having rotor blades that are shaped and proportioned such that when the rotor blades rotate, the rotor blades sweep across the base plate and blood is substantially prevented from collecting between the rotor blades and the housing base plate, a blood flow path being defined over the stator blades and between the rotor and the housing;
- (d) a first blood lubricated mechanical bearing that couples the rotor to the stator and said first bearing having a passage through which blood flows to provide lubrication;
- (e) a second blood lubricated mechanical bearing that couples the rotor to the housing and said second bearing having a passage through which blood flows to provide lubrication;
- (f) a motor, disposed within the housing, for imparting rotational movement to the rotor;
- (g) a first thermoelectric cooler positioned within the stator proximate to the passage in the first blood lubricated mechanical bearing, the first thermoelectric cooler during operation of the pump transferring heat, generated by the first mechanical bearing, from the rotor, the blood flowing proximate to the rotor, the lubricating blood of the first mechanical bearing and the first mechanical bearing, through the stator and to the stator blades, so that the blood flowing along the blood flow path over the stator blades can absorb the heat from the stator blades, and thereby cool the rotor and the first mechanical bearing to maintain the blood flowing proximate to the rotor and the first mechanical bearing below the threshold temperature;
- (h) a second thermoelectric cooler positioned within the housing proximate to the passage in the second blood lubricated mechanical bearing, the second thermoelectric cooler during operation of the pump transferring heat, generated by the second mechanical bearing, from the rotor, the blood flowing proximate to the rotor, the lubricating blood of the second mechanical bearing and the second mechanical bearing, to the housing, so that the blood flowing past the housing can absorb the heat from the housing, and thereby cool the rotor and the second mechanical bearing to maintain the blood flowing proximate to the rotor and the second mechanical bearing below the threshold temperature.
5 more elements
A rotary blood pump for pumping blood through a patient and maintaining the blood flowing through the pump below a temperature at which the blood coagulates, comprising:
- (a) a housing having an inlet and an outlet;
- (b) a first stator member, disposed at the inlet, having a first hub and a first set of stator blades extending from the first hub to the housing;
- (c) a second stator member, disposed at the outlet, having a second hub and a second set of stator blades extending from the second hub to the housing;
- (d) a rotor, disposed between the inlet and the outlet, and rotatably connected to the first stator member by a first blood lubricating mechanical bearing and rotatably connected to the second stator member by a second blood lubricating bearing, each of the first and the second bearings having gaps through which blood flows to lubricate the bearings;
- (e) a motor which imparts rotational movement to the rotor;
- and
- (f) a first thermoelectric device, disposed in the first stator member adjacent to the first mechanical bearing, so that the first thermoelectric device draws heat generated by the first mechanical bearing away from the rotor, the first mechanical bearing, the lubricating blood and the blood flowing proximate to a periphery of the rotor and transfers heat to the first set of stator blades via conductive heat flow, so that the first set of stator blades transfers heat via advective convection to blood flowing around the first set of stator blades to thereby prevent the temperature of the lubricating blood and the blood flowing proximate to the periphery of the rotor from reaching the threshold temperature;
- and
- (g) a second thermoelectric device, disposed in the second stator member adjacent to the second mechanical bearing, so that the second thermoelectric device draws heat generated by the second mechanical bearing away from the rotor, the second mechanical bearing, the lubricating blood and the blood flowing proximate to the periphery of the rotor and transfers heat to the second set of stator blades via conductive heat flow, so that the second set of stator blades transfers heat via advective convection to blood flowing around the first set of stator blades to thereby prevent the temperature of the lubricating blood and the blood flowing proximate to the periphery of the rotor from reaching the threshold temperature.
6 more elements
A method of maintaining blood in a blood pump below a threshold temperature at which the blood tends to coagulate, comprising:
- rotating a rotor disposed within a housing of the blood pump to provide an impetus for blood to pass through the housing;
- lubricating a mechanical bearing that couples the rotor to a stator, disposed within the housing at an inlet of the housing, by passing blood proximal to the mechanical bearing;
- generating heat from operation of the mechanical bearing;
- transferring heat from the mechanical bearing, the rotor, the blood passing proximate to the rotor, the mechanical bearing and the lubricating blood to the stator with a first thermoelectric cooler disposed within the stator;
- passing heat from the stator to the stator blades extending from the stator to the housing;
- and
- distributing heat from the stator blades to the blood flowing through the pump by passing blood over the stator blades.
4 more elements
Dependencies are inferred from the claim text.