Automatic analyzer
View Patent ↗An automatic analyzer which can remove air bubbles in a photometric light path within a reaction tank and can provide accurate measurement results with stability. The automatic analyzer comprises a reaction cell for mixing a sample and a reagent therein, a constant temperature bath for holding water in which the reaction cell is immersed, a suction pipe for sucking the water in the constant temperature bath, a return pipe for returning the water to the constant temperature bath, a pump disposed between the suction pipe and the return pipe and circulating the water, a heater for heating the water circulated in the constant temperature bath by the pump, and an air-bubble removing unit disposed between the suction pipe and the return pipe, having a water-tight structure to hold the constant temperature bath water therein, and removing air bubbles based on a difference in gravity between the water and the air bubbles.
1. An automatic analyzer comprising:
a reaction cell for mixing a sample and a reagent therein;
a constant temperature bath for holding water in which said reaction cell is immersed;
a photometer for measuring target components in a sample;
a suction pipe for sucking the water in said constant temperature bath;
a return pipe for returning the water to said constant temperature bath;
a pump disposed between said suction pipe and said return pipe and circulating the water;
a heater for heating the water circulated in said constant temperature bath by said pump;
a sub-channel for cooling a lamp of said photometer, said sub-channel disposed between said suction pipe and said return pipe; and
an air-bubble removing unit disposed at said sub-channel, having a water-tight structure to hold the constant temperature bath water therein, and removing air bubbles based on a difference in specific gravity between the water and the air bubbles.
2. An automatic analyzer according to claim 1 , wherein a pipe joint position of said air-bubble removing unit on the side connected to said suction pipe is higher than a pipe joint position of said air-bubble removing unit on the side connected to said return pipe.
3. An automatic analyzer according to claim 2 , wherein said air-bubble removing unit is provided with an air bleeding valve for expelling air bubbles accumulated in said air-bubble removing unit to the exterior.
4. An automatic analyzer according to claim 2 , wherein said air-bubble removing unit has a structure with a top left open to an atmosphere.
5. An automatic analyzer according to claim 3 , wherein a valve for draining the water in said constant temperature bath to the exterior is the same as said air bleeding valve provided on said air-bubble removing unit.
6. An automatic analyzer according to claim 5 , further comprising a constant-temperature-bath water injecting valve disposed between said suction pipe and said return pipe and injecting the water into said constant temperature bath.
7. An automatic analyzer according to claim 6 , further comprising a control mechanism for, when the constant temperature bath water is injected into said constant temperature bath by opening said constant-temperature-bath water injecting valve, controlling said valve to be opened and closed such that the constant temperature bath water is injected while said valve provided on said air-bubble removing unit is opened to drain the constant temperature bath water.
8. An automatic analyzer according to claim 7 , wherein said control mechanism is so programmed as to automatically operate in accordance with a predetermined schedule.