Viscometer for in situ monitoring

#1. Technical Field of the Invention

#This invention relates to an apparatus for measuring in situ the viscosity of a fluid. More particularly, the present invention relates to an apparatus which allows the measurement of a useful parameter for measuring the viscosity of a fluid held within a sealed laboratory container wherein the measurement can be obtained without disturbing the fluid held therein.

#2. Description of the Prior Art

#FIG. 1 is a side perspective view of the container made in accordance with the present invention;

#FIG. 2 is a cross sectional view of one embodiment of the composite spherical ball made in accordance with the present invention;

#FIG. 3 is a cross sectional view of a second embodiment of the composite spherical ball made in accordance with the present invention;

#Referring initially to FIG. 1, the container 10 of the present invention may be any number of types of vessels, such as a test tube, an Erlenmeyer flask, a beaker, or laboratory bottle, and such containers are normally formed of glass or other breakable material. In FIG. 1, container 10 is shown as a test tube 11 for holding a fluid 12. A container closure, illustrated as a stopper 14, is located at the open end of test tube 11 for protecting fluid 12 from the atmosphere. Although a stopper is shown for illustrative purposes, the container may be permanently closed air tight by a closure which is not intended for removal and which is pierced by a sterile needle or similar device for inserting fluid 12 into the container. This type of closure may be particularly useful for blood measurements.

#The container 10 of the present invention includes a spherical ball 16 placed within the container prior to the reception of fluid 12 therein. Preferably, spherical ball 16 is packaged with container 10 to form an integral unit and to conveniently allow the container to be equipped for determining the viscosity of a fluid contained therein. Therefore, spherical ball 16 can be placed within container 10 at the factory and the container with ball can then be evacuated, sealed, sterilized and shipped as an integral unit.

#Container 10 may be of any diameter or length, limited only by the constraints imposed for collecting a specified fluid 12. Moreover, spherical ball 16 could be constructed of any material, such as plastic, glass, or metal, that is substantially inert to the fluid held within container 10 and having an absolute density larger than the density of the fluid. However, because the spherical ball 16 is often shipped with glass or frangible containers, container 10 could be shattered during shipping due to the weight of the ball. The bottom of the container is most vulnerable to breakage during shipment. This is especially true when the ball must have a diameter which is large enough to be easily sensed by sensors, discussed in more detail below. If the spherical ball 16 is constructed small enough to reduce the possibility of damage to the container during shipping, the ball will be difficult to sense with conventional sensing devices and will wander as it travels through fluid 12 past the sensors.