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US 4,058,855 AGranted
Cardiac pumping device
OwnerThomas M. Rungeinventor
Life of this patent
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OwnerThomas M. Rungeinventor
Estimating the term…
A pulsatile flow pumping unit adapted to serve as a total cardiac replacement device, a cardiac assist pump for orthotopic placement, for extracorporeal application in conjunction with a membrane oxygenator for cardiopulmonary support during surgery or critical illnesses, for pulsatile flow coronary artery perfusion, and for filling and emptying of an aortic diastolic augmentation balloon for cardiac assist is provided. The pumping unit features simplicity of construction, comparative economy and reliability by utilizing a minimum number of working parts including a large diameter slitted rotary driver and cam operated follower means which avoids close machining tolerances and attendant high cost of manufacturing. The device automatically adjusts its rate of pumping in accordance with both preload (filling pressure) and afterload (pulmonic and systemic pressure) and in addition modifies its stroke volume in a downward direction when confronted with high afterload. The automatic adjustment of the device during operation depending on several variables is accomplished without electronic control or monitoring.
A cardiac pumping unit or the like comprising a housing, a driving motor coupled to the housing and having an output rotary shaft within the housing, a slitted sleeve coupled to the output shaft and rotating therewith and having a continuous spiral slit with widened slit sections near opposite ends of the sleeve, a translatable drive disc for movement axially of the sleeve and housing, radially shiftable drive arms on the drive disc and engageable drivingly with the spiral slit of the rotary sleeve, the drive arms having outer end head elements of a form resisting passage through said slit but being able to pass through said widened slit sections, camming means for said drive arms on the sleeve near the widened slit sections at one end of the sleeve and operable to force said head elements to the interior of the sleeve, a camming means near the other end of the sleeve engageable with the drive arms during movement of the drive disc away from the last-named end of the sleeve and shifting the head elements through the widened slit sections at said other end to the exterior of the sleeve, means continually coupled with said disc and resisting rotation of the disc with said sleeve, pliable fluid chamber means disposed within the housing between the disc and one end of the housing, and one-way opening and one-way closing check valve means connected with said pliable fluid chamber means to control the outflow and inflow of fluid from and to the pumping unit.
Dependencies are inferred from the claim text.