초록 ▼

The impellor of a blood pump is supported by permanent magnets on the impellor and pump housing and stabilized by an electromagnet on the housing. A control circuit supplies current to the electromagnet to maintain the axial position of the impellor at a control position in which the impellor is in

The impellor of a blood pump is supported by permanent magnets on the impellor and pump housing and stabilized by an electromagnet on the housing. A control circuit supplies current to the electromagnet to maintain the axial position of the impellor at a control position in which the impellor is in mechanical equilibrium under permanent magnet forces and static axial forces on the impellor to minimize energy consumption in the support of the impellor. The impellor is rotated magnetically and stator coils in the housing are supplied with electric currents having a frequency and amplitude adjusted in relation to blood pressure at the pump inlet to match the flow characteristics of the pump to physiological characteristics of the natural heart. A cavity is formed in the impellor to match the average specific gravity of the impellor and portions of the suspension and drive systems thereon to the specific gravity of blood to further minimize power consumption by the pump. A valve member can be formed on the impellor to mate with a restriction in the pump inlet for pumps used to assist the pumping action of the natural heart.

대표청구항 ▼

A pump implantable in the human body to provide a replacement for, or an assist to, the natural heart, comprising: a housing constructed of or coated with a blood compatible material having an inlet passage and an outlet passage for connecting the pump into the circulatory system of the person into

A pump implantable in the human body to provide a replacement for, or an assist to, the natural heart, comprising: a housing constructed of or coated with a blood compatible material having an inlet passage and an outlet passage for connecting the pump into the circulatory system of the person into which the pump is implanted, the housing having an impellor chamber fluidly interposed between the inlet passage and the outlet passage; an impellor constructed of or coated with a blood compatible material disposed in the housing impellor chamber and rotatable therein about an impellor rotation axis for drawing blood into the housing inlet passage and discharging blood from the housing outlet passage; magnetic suspension means for magnetically suspending the rotor in said pump chamber out of contact with the walls of the impellor chamber, comprising: permanent magnet impellor support means comprising an assembly of permanent magnets mounted on the impellor and on the housing for exerting forces on the impellor tending to align the rotation axis of the impellor with a selected support axis of the housing while tending to drive the impellor axially away from a selected null position on said support axis at such times that the impellor is axially displaced from the null position; an electromagnet mounted on the housing and positioned thereon to exert a force directed along the support axis on portions of the permanent magnet impellor support means disposed on the impellor at such times that an electric current is passed through the electromagnet, the electromagnet thereby exerting an axial force on the rotor, electromagnet control means mounted on the housing for detecting a displacement of the impellor from a control position of the impellor on the support axis and passing a current through the electromagnet to drive the impellor toward the control position; and impellor drive means mounted on the housing for sensing a preselected physical quantity related to the flow of blood in said circulatory system and magnetically coupled to the impellor for rotating the impellor at a rate varying in accordance with a selected relationship to the value of said quantity.