A pump which adds a moving force to a liquid is popularly used in various fields. Conventionally, as a pump which adds a moving force to a blood, there has been known a blood pump used in an auxiliary artificial heart system (see patent literature 1, for example). “auxiliary artificial heart system” is a system which substitutes for heart function in order to sustain a life of a patient until he receives heart implantation.
FIG. 9A and FIG. 9B are cross-sectional views showing a conventional blood pump 900. FIG. 9A is a cross-sectional view of the blood pump 900, and FIG. 9B is a view showing a range indicated by symbol A in FIG. 9A in an enlarged manner.
As shown in FIG. 9A, the conventional blood pump 900 includes a slide device 901.
The slide device 901 is a slide member which includes: a fixed-side slide member 912 having an annular-shaped first slide surface 914; and a rotary-side slide member 922 having an annular-shaped second slide surface 924, wherein the first slide surface 914 and the second slide surface 924 are configured to opposedly face each other. The slide device 901 is used in a state where an outer peripheral side of the fixed-side slide member 912 and an outer peripheral side of the rotary-side slide member 922 are brought into contact with blood. The slide device 901 is also a constitutional element of a mechanical seal.
The conventional blood pump 900 includes, besides the slide device 901, a fixed part 910, a rotary portion 920, a rotary drive part 930, and a liquid circulation path 940.
The fixed-side slide member 912 is also a member which forms the fixed part 910.
The rotary-side slide member 922 is also a member which forms the rotary part 920.
The rotary part 920 includes, besides the rotary-side slide member 922, an impeller 926 and a rotary shaft 928.
The liquid circulation path 940 is a path through which a predetermined liquid which performs functions such as lubrication, cooling and maintenance of a seal performance in the blood pump 900 is made to circulate. The predetermined liquid is water or a physiological salt solution, for example, and may also be referred to as a cool sealing liquid or a purge liquid.
The liquid circulation path 940 includes a liquid inlet 942, a liquid supply chamber 944, a liquid passing chamber 946, and a liquid outlet 948.
The liquid passing chamber 946 is positioned on an inner peripheral side of the fixed-side slide member 912 and the rotary-side slide member 922. The blood pump 900 is a blood pump of a type which is used in a mode where a predetermined liquid is made to pass through the liquid passing chamber 946.
According to the conventional blood pump 900, with the provision of the slide device 901 having the above-mentioned configuration, the slide device ensures the smooth sliding between the fixed part and the rotary portion and hence, operational stability of the blood pump 900 is enhanced whereby the blood pump 900 can be stably used in sites where the blood pump 900 is required to perform without fail.
USPTO Backgrounds
USPTO Backgrounds