Method of and measuring chamber for measuring properties of particles suspended in liquid

Claim 2

In a measuring chamber for measuring the properties of particles suspended in liquid, said measuring chamber being of the known type that has (a) means defining a measuring opening having an axis, (b) means defining a space upstream of said measuring opening, (c) means driving an electrolytic liquid through said measuring opening, (d) means for generating an electric pulse in response to passage of a suspended particle through said measuring opening, the improvement comprising at least two entrance tubules containing a particle suspension and being disposed in said space, each entrance tubule being formed as a thin-walled elongate capillary tube projecting into said liquid for introducing said particle suspension into said liquid, each entrance tubule having a longitudinal axis being offset with respect to the axis of said measuring opening.

Claim 3

An improvement as defined in claim 1, wherein said entrance tubules are disposed in said space in rotational symmetry with respect to the axis of said measuring opening and at identical distances from said last-named axis.

Claim 4

An improvement as defined in claim 1, including means for charging at least one of said entrance tubules with a sample suspension and means for charging at least one other of said entrance tubules with a calibrating suspension, particles of said calibrating suspension, when passed through said measuring opening, serve to calibrate said pulses generated upon passage of the particles of said sample suspension through said measuring opening.

Claim 5

In a measuring chamber for measuring the properties of particles suspended in liquid, said measuring chamber being of the known type that has (a) means defining a measuring opening having an axis, (b) means defining a space upstream of said measuring opening, (c) means driving an electrolytic liquid through said measuring opening, (d) means for generating an electric pulse in response to passage of a suspended particle through said measuring opening, the improvement comprising A. a plurality of entrance tubules each formed as a thin-walled elongate capillary tube, B. support means carrying said entrance tubules and C. meaNs for the stepwise advancement of said support means to sequentially position said entrance tubules in said space upstream of said measuring opening.

Claim 6

In a measuring chamber for measuring the properties of particles suspended in liquid, said measuring chamber being of the known type that has (a) means defining a measuring opening having an axis, (b) means defining a space upstream of said measuring opening, (c) means driving an electrolytic liquid through said measuring opening, (d) means for generating an electric pulse in response to passage of a suspended particle through said measuring opening, the improvement comprising A. a plurality of entrance tubules each formed as a thin-walled elongate capillary tube, B. support means carrying said entrance tubules and C. meaNs for the stepwise advancement of said support means to sequentially position said entrance tubules in said space upstream of said measuring opening.

Claim 7

An improvement as defined in claim 4, wherein said measuring chamber includes A. a filling station for charging said entrance tubules with a sample suspension, B. a measuring station including said means defining said measuring opening and said space upstream thereof and C. a cleaning station for cleaning said entrance tubules, all three stations being situated along said support means for sequentially receiving said entrance tubules upon said stepwise advancement of said support means.

Claim 8

An improvement as defined in claim 5, including A. a plurality of sample holding vessels and B. sample changer means for sequentially introducing said vessels into said filling station in phase with the sequential introduction of said entrance tubules into said filling station.

Claim 9

An improvement as defined in claim 5, wherein said support means is constituted by a rotary disc, said entrance tubules being secured to, and said stations being arranged along, said rotary disc in a circular array.

Claim 10

An improvement as defined in claim 7, wherein said filling station includes A. a suction head in fluid tight sliding contact with one face of said rotary disc, said suction head being in communication with one end of the entrance tubule positioned in said filling station, B. a sample suspension holder into which extends the other end of said entrance tubule positioned in said filling station and C. vacuum means associated with said suction head for drawing a sample suspension from said sample suspension holder into said entrance tubule positioned in said filling station.

Claim 11

An improvement as defined in claim 7, wherein said cleaning station includes A. a suction head in fluid tight sliding contact with one face of said rotary disc, said suction head being in communication with one end of the entrance tubule positioned in said cleaning station, B. a chamber containing cleaning fluid into which extends the other end of said entrance tubule positioned in said cleaning station and C. vacuum means associated with said suction head for drawing cleaning fluid from said chamber through said entrance tubule positioned in said cleaning station.

Claim 12

In a method of measuring properties of particles of sample suspensions in a measuring chamber, said method including the known steps of (a) driving an electrolytic liquid through a measuring opening of said measuring chamber, (b) introducing in a space upstream of said measuring opening into the flow of said electrolytic liquid said particles of a sample suspension through an entrance tubule formed as a thin-walled elongate capillary tube, (c) generating an electric field across said measuring opening and (d) sensing the electric pulses generated in said measuring chamber in response to the passage of said particles through said measuring opening, the improvement comprising the step of introducing in said space, into said flow and within each measuring process relating to one sample suspension, a calibrating suspension through another entrance tubule formed as a thin-walled elongate capillary tube for calibrating said electric pulses.

Claim 13

In a method of measuring properties of particles of sample suspensions in a measuring chamber, said method including the known steps of (a) driving an electrolytic liquid through a measuring opening of said measuring chamber, (b) introducing in a space upstream of said measuring opening into the flow of said electrolytic liquid said particles of a sample suspension through an entrance tubule formed as a thin-walled elongate capillary tube, (c) generating an electric field across said measuring opening and (d) sensing the electric pulses generated in said measuring chamber in response to the passage of said particles through said measuring opening, the improvement comprising the step of introducing in said space, into said flow and within each measuring process relating to one sample suspension, a calibrating suspension through another entrance tubule formed as a thin-walled elongate capillary tube for calibrating said electric pulses.

Claim 14

A method as defined in claim 10, wherein the flow field of the particle path of the sample suspension within the measuring opening and the flow field of the particle path of the calibrating suspension within the measuring opening are at identical radial distances from the axis of said measuring opening and are at identical radial distances from the edge of said measuring opening.

Claim 15

A method as defined in claim 11, wherein the step of introducing particles of a sample suspension into said flow and the step of introducing particles of a calibrating suspension into said flow are performed simultaneously.

Claim 16

In a method of measuring properties of particles of sample suspEnsions in a measuring chamber, said method including the steps of (a) driving an electrolytic liquid through a measuring opening of said measuring chamber, (b) introducing in a space upstream of said measuring chamber into the flow of said electrolytic liquid said particles of a sample suspension through an entrance tubule formed as a thin-walled elongate capillary tube, (c) generating an electric field across said measuring opening, and (d) sensing the electric pulses generated in said measuring chamber in response to the passage of said particles through said measuring opening, the improvement comprising: A. providing a plurality of tubules in a rotating turn table, which is intermittently rotated such that each of the tubules is brought to a standstill in at least first, second and third positions; B. intermittently driving a gas and a wash liquid alternately through each tubule when in said first position; C. introducing sample suspension into each tubule when in said second position; and D. expelling the contents of the tubules when in said third position into the space before said measuring opening for the purpose of introducing the contents of the individual tubules into the same, whereby the steps (B), (C), and (D) are carried out simultaneously on different tubules in succession.

Claim 17

In a method of measuring properties of particles of sample suspEnsions in a measuring chamber, said method including the steps of (a) driving an electrolytic liquid through a measuring opening of said measuring chamber, (b) introducing in a space upstream of said measuring chamber into the flow of said electrolytic liquid said particles of a sample suspension through an entrance tubule formed as a thin-walled elongate capillary tube, (c) generating an electric field across said measuring opening, and (d) sensing the electric pulses generated in said measuring chamber in response to the passage of said particles through said measuring opening, the improvement comprising: A. providing a plurality of tubules in a rotating turn table, which is intermittently rotated such that each of the tubules is brought to a standstill in at least first, second and third positions; B. intermittently driving a gas and a wash liquid alternately through each tubule when in said first position; C. introducing sample suspension into each tubule when in said second position; and D. expelling the contents of the tubules when in said third position into the space before said measuring opening for the purpose of introducing the contents of the individual tubules into the same, whereby the steps (B), (C), and (D) are carried out simultaneously on different tubules in succession.