三葉片機械心瓣轉軸系統的改良與測試

Modification and Testing of the Pivot System of a Trileaflet Mechanical Heart Valve

陳子偉(Zih-Wei Chen)

指導教授 ： 盧博堅

共同指導教授 ： 劉昭華(Chao-hwa Liu)

淡江大學/工學院/機械與機電工程學系碩士班/碩士(2005年)

https://doi.org/10.6846/TKU.2005.00012

摘要

本研究所設計的三葉片機械心瓣，乃採用中央開孔式的結構，符合人體自然心瓣的運作方式。和傳統的單葉或雙葉機械心瓣相比，此三葉片機械心瓣的中央孔口，可加大中央孔口有效面積、避免血液分離、減少壓差產生。
首先使用Pro/E繪製三葉片機械心瓣，然後利用CNC加工出壓克力放大模型及製作原尺寸模型，最後使用體外模擬在脈動流場下觀察心瓣開關行為。
本機械心瓣因葉片變的較輕薄而使心瓣容易開合，並加大樞紐凹槽的孔徑使葉片轉軸圓端能更完整的包覆在凹槽內，加深樞紐凹槽深度讓心瓣更加深入樞紐凹槽內避免葉片脫落，利用樞紐凸塊脊線當成擋板來拘束心瓣葉片的關閉行為。

關鍵字

三葉片機械心瓣 ； 中央開孔 ； 體外模擬 ； 樞紐凹槽

並列摘要

This research designed trileaflet mechanical heart valve, which opens from the center with a central flow, similar to the function of the human body aortic valve. Compared with the traditional monoleaflet and bileaflet valves, the central orifice of the trileaflet valve increases the effective area, as a result decreasing the pressure drop and the fluid separating.
First, use the Pro/E program to design the trileaflet mechanical heart valve, then use CNC to manufacture the enlarge plastics model, and the titanium alloy prototype model. Finally, we observed the opening and closing behaviors in a mock circulate loop.
The leaflets of the mechanical heart valve become thinner and easier to open and close. The depths of the fillister are deeper, therefore the leaflet hinges were wrapped up and covered more with the fillister to prevent the leaflets to drop off. When the valve is opened, the leaflet contacts the corresponding face of the protruding hinge. When the valve is closed, the ridge tightly seals with the notch of the leaflet.

並列關鍵字

trileaflet mechanical heart valve ； central flow ； mock circulate loop ； fillister

參考文獻

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