Patent ID: 7749449

Claim:
A liquid delivery apparatus comprising: a rotary platform capable of rotating about a center of rotation; a pre-branching chamber provided in the rotary platform and accommodating a liquid; a guiding fluid passage provided in the rotary platform, having an inlet end section that is connected to the pre-branching chamber and holds the liquid in the pre-branching chamber by a capillary force, extending from the inlet end section in a direction away from the center of rotation, and having an outlet end section at an opposite side to the inlet end section; a branching chamber provided in the rotary platform at a position farther from the center of rotation than the pre-branching chamber, spatially enclosed except for an air aperture, and having a first wall surface that is arranged at a centripetal direction side and at which the outlet end section of the guiding fluid passage opens, second wall surface that is arranged at a centrifugal direction side and is opposed to the first wall surface, and separation wall that extends from the second wall surface toward the first wall surface to define a plurality of branching compartments, wherein the first wall surface has a spread angle from the outlet end section of the guiding fluid passage that is an obtuse angle at least in a direction of arrangement of the plurality of branching compartments, and the separation wall has a distal end that is arranged in the vicinity of a imaginary line extending in the centrifugal direction from the outlet end section of the guiding fluid passage and opposed to the first wall surface with a distance; and a rotation drive unit for rotating the rotary platform about the center of rotation at a rotation speed between 1500 rpm and 2000 rpm, wherein the liquid is a blood serum, and wherein a cross sectional area of the guiding fluid passage is in a range between 1 μm 2 and 4 mm 2 .