Hemostasis Analysis Device and Method
Apparatus for measuring hemostasis includes a container for holding a sample to be tested and a bobber configured to be buoyantly suspended on the sample. A magnet is secured to the bobber. A drive assembly is coupled to the container for driving the container in an oscillating motion. A magnetic field generator is disposed adjacent the container and configured to generate a magnetic field in the vicinity of the magnet. A magnetic field strength detector is disposed adjacent the container, and the magnetic field strength detector is configured to sense changes in the magnetic field as a result of movement of the bobber and magnet responsive to the oscillating motion of the container and clotting of the sample.
1 . Apparatus for measuring hemostasis comprising:
a container for holding a sample to be tested;
a bobber configured to be buoyantly suspended on or within the sample and a magnet secured to the bobber;
a drive assembly coupled to the container for driving the container in an oscillating motion;
a magnetic field generator disposed adjacent the container and configured to generate a magnetic field in the vicinity of the magnet; and
a magnetic field strength detector disposed adjacent the container, the magnetic field strength detector configured to sense changes in the magnetic field as a result of movement of the bobber and magnet responsive to the oscillating motion of the container and clotting of the sample.
2 . The apparatus of claim 1 , wherein the container and the bobber each are formed as cylinders.
3 . The apparatus of claim 2 , comprising a space defined between an inner wall of the container and an outer surface of the bobber, the sample being disposed in the space.
4 . The apparatus of claim 1 , an aligning structure coupled between the container and the bobber, the aligning structure configured to align bobber within the container.
5 . The apparatus of claim 4 , wherein the aligning structure comprises a pintle formed in the container and a dimple formed on the bobber.
6 . The apparatus of claim 5 , wherein the aligning structure comprises an optional locating member coupled to the bobber.
7 . The apparatus of claim 1 , wherein the container or bobber is formed of medical grade plastic
8 . The apparatus of claim 1 , wherein the bobber is formed with a cavity into which the magnet is disposed.
9 . The apparatus of claim 1 , wherein the magnet is encapsulated within the bobber
10 . The apparatus of claim 1 , wherein the magnetic field generator comprises a permanent magnet disposed adjacent the container.
11 . The apparatus of claim 1 , wherein the magnetic field generator comprises first and second permanent magnets disposed adjacent the container.
12 . The apparatus of claim 1 , wherein the magnetic field generator provides a predetermined resistance to rotation of the bobber by interaction with the magnet.
13 . The apparatus of claim 1 , the drive assembly comprising a cam and motor arrangement, a direct motor drive or a gear drive
14 . The apparatus of claim 1 , container and bobber being configured to be replaceably inserted into the apparatus.
15 . A container and bobber assembly for use with the apparatus of claim 1 .
16 . The apparatus of claim 1 , the magnetic field strength detector configured to sense displacement of the bobber from an aligned position by sensing variations of the magnetic field.
17 . The apparatus of claim 1 , the magnetic field strength detector configured to provide a signal related to the strength of the sample undergoing clotting.
18 . The apparatus of claim 17 , the magnetic field strength detector coupled to a processing device.
19 . The apparatus of claim 1 , the magnetic field strength generator being configured to provide a magnetic field strength of a predetermined strength sufficient to at least partially restrain movement of the magnet and hence the bobber in view of a maximum clot strength of the sample.
20 . The apparatus of claim 1 , the magnetic field strength generator being configured to provide a magnetic field strength of a predetermined strength sufficiently low so as to permit movement of the magnet and hence the bobber substantially with initial clot formation.