Particle volume and cross-section measurement

Claim 3

An apparatus as claimed in claim 1, wherein the diameter of said second measuring opening is larger than the diameter of said first measuring opening.

Claim 4

An apparatus as claimed in claim 1, wherein said first measuring opening has a cylindrical shape, with a length of about 15 microns and a diameter of about 40 microns.

Claim 5

An apparatus as claimed in claim 1, wherein said first measuring opening has a conical shape, with a length of about 22 microns, an inlet diameter of about 50 microns, and an outlet diameter of about 43 microns.

Claim 6

An apparatus as claimed in claim 1, wherein at least the outlet section of said tube means, and the means forming the first measuring opening, include building blocks containing said outlet section and said first measuring opening, and a support element means for holding the outlet section spaced from the first measuring opening.

Claim 7

An apparatus as claimed in claim 5, further comprising means for exchangeably mounting said support element means relative to said vessel means.

Claim 8

An apparatus as claimed in claim 6, wherein said vessel means includes a dividing wall and said support element means forms a part of said dividing wall.

Claim 9

An apparatus as claimed in claim 5, wherein said support element means includes a tube and said building blocks are located in said tube.

Claim 10

An apparatus as claimed in claim 7, wherein said support element means includes a tube, said building blocks are located in said tube, and said tube is fitted into mating receiving areas in said dividing wall.

Claim 11

An apparatus as claimed in claim 8, said tube having hole means located for placing chamber area within said tube and between said building blocks in communication with the surrounding of the tube.

Claim 12

An apparatus as claimed in claim 1, wherein the outlet section of said tube means and the means forming said measuring openings include building blocks containing said outlet section, said fIrst measuring opening, and said second measuring opening, and a support element means for holding the outlet section spaced from the first measuring opening and the first measuring opening spaced from the second measuring opening, and wherein said support element means includes a tube and said building blocks are located within said tube.

Claim 13

An apparatus as claimed in claim 11, said tube having hole means located for placing chamber area within said tube and between said building blocks in communication with the surrounding of the tube, with the hole means opening into the area between said outlet section and said first measuring opening being angularly offset with respect to the hole means opening into the area between said first measuring opening and said second measuring opening.

Claim 14

An apparatus as claimed in claim 10, said hole means having conical shapes.

Claim 15

An apparatus as claimed in claim 8, said tube containing a capillary tube means for conducting test liquid, said capillary tube means reaching to the side of said outlet opening opposite to that facing said first measuring opening.

Claim 16

An apparatus as claimed in claim 9, wherein the mating portions of said tube and dividing wall are conically shaped.

Claim 17

An apparatus as claimed in claim 8, wherein said tube is glass and the building blocks are drilled saphires glass-bonded to the inner surface of said tube.

Claim 18

In an apparatus for counting and classifying particles suspended in a test liquid, which apparatus operates according to the Coulter process and includes a first vessel containing electrolyte, a second vessel whose interior is in communication with the interior of the first vessel through a first small measuring opening through which electrolyte can flow from the first vessel into the second vessel, a device for feeding the test liquid to the measuring opening and whose outlet opening is located upstream coaxially and a small distance before the measuring opening such that electrolyte flowing into the measuring opening sucks test suspension out of the outlet opening and transports it into the center of the measuring opening, and electrodes placed at different electric potentials and arranged to reach down into the liquid in the vessels, with the electrodes being connected to an electrical circuit in which a current change is caused by the movement of a particle through the measuring opening, the amplitude of such current change being a measure of the size of the particle, the improvement comprising means presenting a second measuring opening arranged after the first measuring opening in the liquid stream, the opening diameters and/or the lengths of the two measuring openings being coordinated with one another such that one measuring opening allows essentially the volume and the other measuring opening essentially the cross section of the particles to be measured.

Claim 19

In an apparatus for counting and classifying particles suspended in a test liquid, which apparatus operates according to the Coulter process and includes a first vessel containing electrolyte, a second vessel whose interior is in communication with the interior of the first vessel through a first small measuring opening through which electrolyte can flow from the first vessel into the second vessel, a device for feeding the test liquid to the measuring opening and whose outlet opening is located upstream coaxially and a small distance before the measuring opening such that electrolyte flowing into the measuring opening sucks test suspension out of the outlet opening and transports it into the center of the measuring opening, and electrodes placed at different electric potentials and arranged to reach down into the liquid in the vessels, with the electrodes being connected to an electrical circuit in which a current change is caused by the movement of a particle through the measuring opening, the amplitude of such current change being a measure of the size of the particle, the improvement comprising means presenting a second measuring opening arranged after the first measuring opening in the liquid stream, the opening diameters and/or the lengths of the two measuring openings being coordinated with one another such that one measuring opening allows essentially the volume and the other measuring opening essentially the cross section of the particles to be measured.

Claim 22

A method as claimed in claim 18, further comprising flowing the electrolyte and entrained suspension coming from said first measuring opening homogeneously from the first measuring opening into the second measuring opening.

Claim 23

A method as claimed in claim 18, further comprising matching the lengths of the particles and the length of said first measuring opening such that the length of the first measuring opening is shorter than the lengths of the particles.

Claim 24

A method as claimed in claim 18, further comprising flowing a greater amount of electrolyte through said second measuring opening than comes from said first measuring opening.

Claim 25

A method as claimed in claim 18, further comprising choosing said particles to include deformable particles and matching the dimensions of said measuring openings to the dimensions of the deformable particles such that the deformable particles are essentially deformed only in one of the measuring openings.

Claim 26

A method as claimed in claim 18, further comprising placing electrodes of different potential on either end of said other measuring opening for creating an electric field through said other measuring opening, and matching the lengths of the particles and the length of said other measuring opening such that the particle remains partially in a region of weakened field strength, when passing through the measuring opening.

Claim 27

A method as claimed in claim 18, further comprising focusing said suspension at said first measuring opening substantially in the absence of an electric field and measuring particle volume at said second measuring opening by sensing resistance changes in the resistance of said second measuring opening.

Claim 28

A method as claimed in claim 18, further comprising sensing the amplitudes of particle-caused changes in the electrical resistance of said other opening, for determining particle cross sections.

Claim 29

A method as claimed in claim 18, further comprising sensing the durations of particle-caused changes in the electrical resistance of said other opening, for determining particle cross sections.

Claim 30

A method as claimed in claim 18, further comprising sensing the amplitudes and the durations of particle-caused changes in the electrical resistance of said other opening, for determining particle cross sections.

Claim 31

A method as claimed in claim 27, further comprising forming the ratio of duration to amplitude, for determining particle cross sections.

Claim 32

A method as claimed in claim 18, further comprising sensing only changes in the electrical resistance of said other opening which exceed a predetermined amplitude, for determining particle cross sections.

Claim 33

A method as claimed in claim 18, further comprising sensing as the durations of particle-caused changes in the electrical resistance of said other opening those portions of changes lying above a predetermined amplitude level, for determining particle cross sections.

Claim 34

A method as claimed in claim 18, further comprising sensing as the durations of particle-caused changes in the electrical resistance of said other opening those portions of changes lying between the reaching of the maximum change and the fall to a predetermined percentage of the maximum change, for determining particle cross sections.