DE2855371A1 - Blood cell counter with conduit for sample flow - responds to single manual operation to admit blood sample to conduit and simultaneously actuate counter - Google Patents

Abstract

A chamber receives a blood sample which flows from the chamber through a conduit. The conduit is normally closed but is opened for flow of the sample, the sample being drawn through the conduit upon its being opened. A counter counts particles in the sample as it flow through the conduit. A single manual operation opens the conduit for flow of a sample and concomitantly actuates the counter to count the particles in the sample flowing through the conduit. A method of counting particles suspended in the blood is also disclosed.

Description

Device and method for counting particles

The invention relates to, and particularly relates to, Telchen counting devices an apparatus and method for counting particles, such as blood cells, which are suspended in a liquid medium.

In medicine, for example, particle counters are used to measure white Count blood cells in a patient's blood sample, with the resulting count is used to make a diagnosis. Many methods are already used for particle counting been used to those using the colorimetry, the microscope counting a chamber, the light scattering of particles in a non-coaxial or coaxial (Layer) flow and the hole conductivity count belong. The latter Procedure is for example off U.S. Patents 2,656,5508 and 2,869 078 known. In addition, some particle counters with hole conductivity counting work, in addition, air bubbles are introduced into the flow of a sample to the sample divide into two or more than two-part-e- zü-, and the volume of these parts, for that.: One½ cell counting is performed using electro-optical Gates measured. This process is described, for example, in US Pat. No. 3,657 725 known.

These known meters all require pumps, solenoids or Engines and engines are quite expensive, bulky in size, and have to go with them Electricity from public electricity supply sources are also supplied Test procedures that must be carried out when using one of these counters, in order to achieve accurate results, generally umPaug-rich and complex. Such counters therefore usually found only in a hospital or laboratory. Through this becomes the job of a doctor to make a diagnosis about a patient's illness to ask, complicated and unduly prolonged if the doctor thinks that one Cell counting should be done on a sample of patient's blood as he take a blood sample from the patient, label it, send it to a laboratory Send an examination and then wait for the results of the examination before leaving can prescribe treatment for the patient.

The invention provides an apparatus for counting particles, such as blood cells, which are suspended in a liquid medium, with the following properties: es does not require a complicated test setup and no external Power source; it is easy to operate and a particle count is done by a single manual Actuation initiated; It can be used to count several particles on a single one Sample, for example a blood sample from a patient #, can be carried out can be easily calibrated for consistently accurate data when an or multiple counts are made; it does a particle count for a predetermined one Volume of a sample by; it provides a ~ particle count in standard units of measurement, so that no conversion is required to obtain usable data; let it waste fluids easily collect with him and easily dispose of; it has a reusable Drive source; it can be cleaned easily to avoid clogging and pollution to prevent from; its components most likely to become clogged, are easily interchangeable; it is light in weight, compact, portable and independently, so that it can be used, for example, in the field on expeditions or during military operations Maneuver or used by a doctor in his practice and then by him in his Doctor's case can be transported to a patient's house to be used there will; and it is inexpensive and yet it is robust in construction and operation Reliable.

The device according to the invention for counting particles, such as blood cells, which # are suspended in a liquid medium, contains, in short, a chamber for receiving a sample of the liquid medium containing the particles and a conduit through which the sample flows out of the chamber. Institutions that support the Normally plug the line, are opened to allow the sample to flow through can, and other devices suck after opening the line closing devices the sample through the line.

A counter counts the particles in the sample when they are through the line flows, and manually operated devices open the line closing devices, so that a sample can flow through it, and press at the same time the counter to keep the particles in the sample flowing through the conduit are counted.

The invention also includes a method for counting particles, such as blood cells suspended in a liquid medium by introduction a first sample of a liquid medium containing a known amount of particles in a predetermined volume, in a chamber. The first sample will then sucked out of the chamber through a conduit and the particles are in the first sample counted when it flows through the line. The number of counts in the first sample Particle is divided by a number that is equal to the known amount, um thereby generating a calibration factor. A second sample of a liquid medium, containing an unknown amount of particles is introduced into the chamber and then sucked through the pipe, and the particles in the second sample are counted, when it flows through the pipe. The number counted in the second sample Particle is divided by the calibration factor to produce a number representing the actual Represents particle count for the second sample.

Several embodiments of the invention are discussed below Described in more detail with reference to the accompanying drawings. They show: FIG. 1 a schematic representation and a block diagram of a particle counter according to the invention, Fig. 1A shows the moved position of part of the device of Fig. 1, FIG. 2 shows a perspective and partially broken away representation of a first Embodiment of the particle counter according to the invention, Fig. 3 is an exploded view enlarged view on the line 3-3 in Fig. 2 of an arrangement through which a Sample of a liquid medium flows and within which the particles in the sample 4 is a circuit diagram of a first embodiment of a particle counting circuit of the device, Fig. 5 is a longitudinal section through a drive source for the device,.

6 is a perspective, partially broken away view of a second embodiment of the particle counter according to the invention, Fig. 7 is a sectional view of the particle counter of Fig. 6 on the line 7-7, Fig. 8 is an exploded view Representation of part of a second embodiment of the device according to the invention: #rng, which shows the valve arrangement of the same, and Fig. 9 is a circuit diagram of a second Embodiment of the particle counting circuit of the device.

In the drawings, the same parts have the same reference numerals.

In the drawings the device according to the invention is for counting Particles such as blood cells suspended in a liquid medium in its The whole is designated by 1 and contains a chamber designated as a whole by 3 for receiving a sample of the liquid medium. The sample flows out of the chamber 3 by a line designated as a whole with 5, which is normally closed but is opened for the sample to flow through. According to FIGS. 1 and 2, the chamber 3 has the shape of a shaft W, which is used to hold a sample above is open and one bottom B and Pages 7 has. The shaft W is formed in a block of synthetic resin or other suitable material. The line 5 has an inlet end 9 which extends down into the shaft W to his Floor extends. The bottom B of the well W and the inlet end 9 of the line 5 are between a closed position in which the bottom is the inlet end the line closes, and an open position in which the bottom and the inlet end are spaced apart for the sample to enter the conduit can, relatively agile. For this purpose the inlet end 9 of the line 5 is stationary and the bottom B of the shaft W is flexible and bends out of the closed Position of the conduit in which the soil contacts the inlet end of the conduit in the open position of the line. A vacuum source 11 sucks in the sample opening the inlet end of conduit 5 therethrough and particles in of the sample are counted by a particle counting and display circuit 13 when the sample flows through the conduit. By manually operating one in its entirety labeled V valve, the closed line 5 is opened so that a Sample flows through it, and by manual actuation of the valve is simultaneously the counting circuit 13 is operated so that the particles in the flowing through the conduit Sample to be counted.

The bottom B of the shaft W is a flexible plate or membrane 15, which is made of a suitable elastomeric material such as rubber, and through manual actuation of the valve V, the membrane is bent. According to FIGS. 1 and 4, the valve V includes a lever L for moving the plate 15 away from the inlet end 9 of the line 5. The lever L is over a pivot P movable, which is arranged at one end of the lever. At the other end of the lever (its free end) is a key K for moving the lever L around its Trunnion when manually using a force. is exerted on the key. A spring 17, which has its seat on the inner surface of the bottom of a frame F in which the Particle counter 1 is housed, tensions the lever and the flexible plate 15 in the direction of the closed position of the line 5. By moving the Lever around its pivot when a force is manually applied to the button, the plate 15 is moved downward and away from the inlet end 9 of the conduit 5. This opens the inlet end of the conduit and the sample in well W can then be sucked into the line. The counting circuit 13 includes a reset switch 19, which by the lever L simultaneously with the movement of the plate 15 from the closed position of the line can be actuated. The switch 19 is a microswitch, which is arranged below the lever L and has an actuator 21 which is touched and depressed by the lever when it is around its pivot turns to close the switch. The switch 19 is opened when the actuator returns to its normal position after releasing the lever. By operating the switch 19, the counting circuit is reset so that Particles in the next sample can be counted later by the line flows.

The counting circuit contains one designated by 23 in its entirety Particle detector that detects the particles in the sample and an electrical one Signal generated which reports the detected particles. to for this purpose the medium in which the particles are suspended is electrical conductive and an electrical circuit is closed over the sample, if this flows through the line.

The conductivity of this circuit is determined by the particles in the Changes the sample and thereby generates the electrical signal. According to Figs. 2-4 contains the particle detector 23 has two electrodes Ei and E2 located downstream from the inlet end 9 of the line 5 are arranged. According to Fig. 3, the electrode El has a tubular, cylindrical shape and a first and a second lug 25 and 27 with a smaller one Diameter, the diameter of the second approach being smaller than that of the first approach. The electrode El has a central longitudinal bore 29, which of the End 31 of lug 27 out inwardly and partially through the main body of the electrode leads. A radial bore 33 leads from the inner end of the bore 29 to the outer one Area of the electrode El. A pipe part 35 of the line 5 has one end which the Inlet end 9 of the line forms, while the other end of the pipe part in the radial bore 33 of the electrode El is added. A centering ring 37 is dimensioned so that he fits on the approach 25 of the electrode El, and an O-ring 39 is so dimensioned that it fits over the approach 27 of the electrode El. The centering ring 37 consists of one electrically non-conductive material, such as a synthetic resin material, that from E. I. duPont de Nemours & Co. under the trademark "Lucite" is distributed.

The other electrode E2 also has a tubular cylindrical one Shape and a first and a second lug 25A and 27A of smaller diameter, where the diameter of the second approach is smaller than that of the first approach. These approaches correspond in their size and shape to those of Electrode E1 and a centering ring 37A and an O-ring 39A fit these approaches in the same way as the centering ring 37 and the O-ring 39 on the corresponding Approaches to the electrode El fit. The electrode E2 has a third extension 41 smaller diameter, which is on the smaller of the two lugs 25A, 27A Located opposite the diameter of the main body of the electrode E2, and a Pipe part 43 of the line 5 fits together with the extension 41. The electrode E2 has a central longitudinal bore 45, so that a sample, which in the inlet end 9 of the conduit 5 enters, through the pipe part 35 of the line, the electrode E1, the electrode E2 and the pipe part 43 flows to the vacuum source 11. Of a battery 47 is one Clamp with the electrode Ei over a resistor R1 and with the electrode E2 over connected to a capacitor C1. The electrode Ei continues with the counting part of the Particle counting circuit connected via a shielded conductor 49, while the Electrode t2 and the shielding of the conductor are connected to ground. An electrical circuit is closed in this way between the electrodes over the sample when the Sample flows through both electrodes at the same time.

A disc-shaped, electrically non-conductive part, which is made of a membrane M is arranged between the electrodes E1 and E2 and through centering rings 37 and 37A in line with the fluid flow path through the conduit 5 aligned. The membrane M, which consists for example of a plastic film, which is sold under the trademark "Mylar" has a hole A so dimensioned is that the particles in the sample are separated by the Go through the hole have to. The size of the hole is, for example, 100 jun. Since the membrane M is non-conductive is, the conductivity of the circuit between the electrodes changes in dependence on the degree of blockage of the hole A which occurs when a particle goes through the hole. Thus, each particle in the sample affects temporarily the conductivity of the circuit between the electrodes and it becomes a self The resulting signal element of the electrical signal is generated at the electrode El and transmitted through shielded conductor 49 to the input of the counting circuit.

A clamping and retaining screw 50 is in a threaded hole 51 in the Side of the frame F and the tip of the screw is on the rear Surface of the electrode El. The screw 50, when tightened, exercises one Pressure on the electrodes E1 and E2, the membrane M and the centering rings 37, 37A to form a liquid-tight arrangement, through which a sample is sucked. The centering ring 37, the membrane M and the centering ring 37A are glued to one another in a layer arrangement and form a removable, disposable punch unit U, with the centering rings ensure simple and functional alignment.

The cylindrical parts 25 and 25A of the electrodes El and

E2 form connecting pieces which of the centering rings 37 and 37A be included.

According to FIG. 4, the signal elements generated at the electrode E1 an amplifier and discriminator part 53 of the counting circuit 13 is supplied. Each The signal element is connected to a first amplifier stage via a coupling capacitor C2 55 applied, the an operational amplifier 57 and resistors R2 and contains R3. The amplified signal elements are then passed through a filter, which consists of a coupling capacitor C3 and a resistor R4, to a second Amplifier stage 58 is applied, which has an operational amplifier 59 and resistors R5 and contains R6. The output signal of the operational amplifier 59 is via a Coupling capacitor C4 applied to a voltage divider 61, which consists of resistors R7 and R8 consists. The output signal of the voltage divider 61 is via a resistor R9 to an input of a comparator 63, which is an operational amplifier acts, created. The other input signal of the comparator 63, which is via a Resistor R10 is supplied, is a voltage that is applied to a potentiometer 65- is accessed, the setting of which is the minimum size of in a through the Line sucked sample establishes detected particles that are counted. if for example, counting white blood cells in a patient's blood sample therefore the potentiometer is set so that only particles are counted whose Size, for example, exceeds 4 µm.

The amplitude of each signal element applied to voltage divider 61 changes the value of the input signal to the comparator 63 from the voltage divider and, if-this resulting value, the value obtained by setting the potentiometer 65 exceeds the specified threshold value, becomes a signal element of a first count signal delivered at the output of the comparator 63.

Signal elements of the first counting signal are sent to a reducer 67 is applied to a counting circuit 68 and the scaler counts the signal elements and provides a signal element one for every predetermined number of signal elements second Counting signal. The coaster, which works in the known way, is made by the company. Solid State Scientific, Inc., Montgomeryville, Pennsylvania, V.St.A., under their Model name SCL 4040A sold. The signal elements of the second count signal are applied to one input of a NAND circuit G1, which has a second input to which a sampling signal is applied by a computer chip 69. The chip 69 is a 6-digit computer chip whose mode of operation is known and that of from National Semiconductor Corp., Santa Clara, California, V.St.A., under their Model name MM 5736 is sold. The digital output signal of the NAND circuit G1 is applied to one input of a NAND circuit G2, which has a second input to which the digital output signal of a NAND circuit G3 is applied. the NAND circuit G3 is by operating the reset switch 19 on the manual actuatable valve V is controlled and has an input to which a signal is applied is, which is from an RC element 71 from a capacitor C5 and a resistor R11 is delivered when the switch is closed. The NAND circuit G3 has a second input to which a sampling signal from the computer chip 69 is applied.

The signal elements of the second count signal from the NAND circuit G2 are passed, are applied to an adding input of the computer chip 69, which converts the content of a counter within the chip to each signal element one increased. The number of second count signal elements generated by the computer chip 69 are counted, a display unit 73 via a display control circuit 75 which converts the binary value of the count value into its decimal equivalent. The digital display unit contains a decimal point, which is illuminated by the Computer chip 69 controlled by an npn transistor Q1 and resistors R12 and R13 will. The display control circuit 75 is commercially available from National Semiconductor Corp., Santa Clara, California V.St.A. under their model designation SN 75492. For the convenience of the user, the display is in easily interpretable units shown, which are 106 cells / microliter.

The amount of the sample flowing through the line 5 is precisely measured and that is achieved by allowing the flow of the sample over a predetermined length The line is sensed and the counting circuit is released to allow them to particle counts in the sample when it reaches the upstream end of the predetermined length, and by preventing the counting circuit from counting particles in the sample, when it reaches the downstream end of the predetermined length. Because the diameter of the line 5 and the predetermined length are known, the number of through the counting circuit counts particles and the resultant indication for a predetermined one Volume of the sample.

An electrode E3 is at the upstream end of the predetermined Length and an electrode E4 is arranged at the downstream end thereof. The electrodes have the same shape, are each cylindrical and have a central one Longitudinal hole, the diameter of which corresponds to that of the pipe. The electrode is E3 to the battery 47 via a resistor R14 and to an input of a comparator 77, which is an operational amplifier, through a resistor R15 connected. The electrode E4 is also connected to the battery 47. Before the front edge of the sample has reached electrode E3 the amplitude of the voltage applied to one input of the comparator 77 first value. The comparator 77 has a second input, which is on a Reference value is located, which is determined by the setting of a potentiometer 79 is. For the above initial state, the value of the control signal exceeds the reference value. When the leading edge of the sample reaches electrode E3, a circuit X1 with low impedance via the medium and the electrode E2 closed to ground.

As a result, that supplied to the comparator 77 from the electrode E3 falls Value below the reference value. When the leading edge of the sample reaches electrode E4, becomes a second low-impedance circuit X2 between electrodes E3 and E4 created. The two circuits act as a voltage divider and as a result the voltage value supplied to the comparator from the electrode E3 rises above the Reference value. Whenever the value of the signal generated at electrode E3 drops below the reference value, a first control signal, which has an H value, generated by the comparator 77. If the value exceeds the reference value, decreases the digital output signal of the comparator 77 becomes an L value and it is through the comparator generates a second control signal.

The digital output signal of the comparator 77 is applied to both inputs to a NAND circuit G4 acting as an inverter and to an input a NAND circuit G5 via an RC element made up of a capacitor C6 and a resistor R16. The digital output signal of the NAND circuit G4 is sent to the reset input of the coaster 67 is applied.

Whenever a first control signal (with the signal value H) is applied to the NAND circuit G4, this outputs an L signal to the coaster 67, which enables the scaler so that the signal elements of the first count signal are counted. If, however, a second control signal (with the signal value L) is sent to the NAND circuit G4 is output, an H signal is sent to the reset input of the reducer 67 is applied, which locks the coaster and the value of its content to zero resets. The NAND circuit G5 has a second input, the one through the computer chip 69 generated scanning signal receives. The digital output signal of the NAND circuit G5 is applied to both inputs of a NAND circuit G6 and the digital output signal this NAND circuit is applied to the "1" input of the computer chip 69.

The measuring electrodes E3 and E4 can instead also be upstream the sensing electrodes Ei and E2 are arranged and that the electrode E3 next to the Electrode E2. In this configuration, the operation of the counting and display circuit is same as that described above, except that the creation of a first Control signal occurs when the rear end of the sample leaves the electrode E4, and that the generation of a second control signal occurs when the rear end the sample leaves the electrode E3. The measuring system of the device described here will thus count correctly without modification if the direction of flow of the sample is reversed and the front end or the front edge sequentially the electrodes E4, E3, E2 and Ei touched.

The vacuum source 11, by means of which a sample through the line 5 is a conventional disposable evacuated container 81. One pierceable membrane 83 extends over the bottom of the container 81 and the Conduit has a lance-shaped outlet end 85. Referring to Figure 1, this is downstream The end of the line 5 is bent upwards by 900 and the frame P has a socket 87 in its upper surface, which is dimensioned to receive the container 81 can. Instead, as shown in FIG. 2, the downstream end of the line can be straight and the socket to be formed in the side of the frame so that the container when he is attached, protrudes outward on the side of the frame. In every embodiment causes the introduction of the container 81 into its socket 87 that the lance-shaped The end of the line 5 pierces the membrane 83. Well every time that Manually operated valve V is opened, the sample in the shaft W by means of suction Sucked off via line 5 and collected in container 81. If a container is full or insufficient driving force to aspirate a sample from the Schacht delivers more, it is withdrawn from its socket and in a suitable manner eliminated. Since the disposal of the container also includes the disposal of the samples, which have been sucked through the line 5 are cleaning work after a test minimal. The pressure difference created by the container vacuum prevents that samples sucked into the container flow back into the line, and reduced the possibility of contamination of samples drawn in later or a blockage.

The particle counter works as follows: If, for example, a red blood cell count is performed, the user takes the first a predetermined amount of patient's blood and dissolve it in a saline solution, for example a 0.85 percent saline solution. A sample of the resulting Suspension is then introduced into the shaft W and the lever L is depressed manually. This pushes the plate 15 downwards and the inlet end of the conduit 5 opened.

At the same time, the movement of the lever L turns the reset switch 19 is closed and a voltage is applied to the RC element 71. This has the consequence that temporarily an H signal applied to one input of the NAND circuit G3 will. The other input of the NAND circuit G3 is made periodic by the computer chip 69 sampled, the sampling signal is a pulse, for example with a Repetition frequency of 1 kHz is supplied and an H signal at the input of the NAND circuit G3 generated. If both input signals of the NAND circuit G3 have an H value, this circuit outputs an L signal to the NAND circuit G2. This gives the The output signal of the NAND circuit G2 has an H value, which is the content of the computer chip clears. After a period of time that is determined by the time constant of the RC element 71 becomes, the one input signal of the NAND circuit G3 becomes an L value, whereby the output of this circuit assumes an H value. This L input signal the NAND circuit G3 is maintained after the lever L is released and the reset switch 19 is open again #.

When the lever L is depressed, the sample is transferred from the shaft W. the line 5 and through the hole A in the between the sensing electrodes E1 and E2 arranged membrane sucked through. Every particle is affected when it passes through the hole A passes through it, temporarily reducing the conductivity of the circuit that runs between the electrodes through the electric conductive medium is built up, and leads to the generation of a signal element at the electrode Ei, that of the first Amplifier stage 55 of the counting circuit is fed. The amplitude of each on the electrode E1 generated signal element is a function of the size of the one passing through hole A. Particle. After a signal element has passed through two amplifier stages is, it is fed to the comparator 63 via the voltage divider 61. If the If the signal amplitude exceeds the reference value, then becomes a signal element of the first counting signal generated by the comparator and fed to the reducer 67. Otherwise it will no first count signal element generated. Will continue even if the size of one sensed particle exceeds the reference value, so that a first count signal element is generated, this signal element by the scaler or counter 67 only counted, # if the front edge of the sample flowing in the line touches the measuring electrode E3 has reached at which point in time a first control signal from the comparator 77 supplied and thereby to the NAND circuit G5 an H input signal therefrom Counter is applied, the short duration of which is determined by the time constant of the RC element is determined. The other input of the NAND circuit G5 is through the computer chip 69 is sampled in the manner explained above and, if a sampling pulse is applied to the relevant Input of the NAND circuit G5 appears, takes the output signal of this circuit a value L. This signal value is inverted by the NAND circuit G6 and the resulting high signal is applied to the input of the chip. The coaster 67 is enabled by the output of the NAND circuit G4 and counts each signal element of the first counting signal supplied to it. For, for example, each 128 signal elements counted by the scaler 61 are there this a signal element of the second count signal to the NAND circuit G1, so that the one input of this circuit receives an H signal. The other input of the NAND circuit G1 is sampled by the computer chip 69 in the same way as the NAND circuit G3 and, when a sampling pulse is applied to the NAND circuit G1, both inputs lead the same has a signal with the value H and its output signal assumes the value L. Since the output signal of the NAND circuit G1, which is at one input of the NAND circuit G2 is present, which is now an H signal, is replaced by the L signal, which is sent to the other Input of the NAND circuit G2 is output through the NAND circuit G1, the output signal the NAND circuit G2 is given an H value and this H signal is applied to the adding input of the chip, in which it increases the content of an internal register by one and causes the result to be displayed as a digital number by the display unit 73 will. This continues until the front edge of the sample reaches electrode E4, at what point in time the coaster 67 is blocked and, although particles, their Size above the predetermined minimum size is sensed in the remainder of the sample no signals of the second counting signal are generated and the displayed one Number is not changed. When the rest of the sample has been sucked out of the shaft W. the lever L is released and returns to its original position.

However, as explained above, this becomes the signal value of the input signal the NAND circuit G3 is not influenced, due to the action of the RC element 71 already has the value L.

When the hole A in the membrane M is due to clumped particles or clogged by foreign particles in a sample can do that Flow system can be flushed using a hypodermic syringe. to for this purpose, the container 81 is removed from its socket 87 and the end of the Syringe is inserted over the downstream end 85 of the conduit. The syringe is provided with a rubber washer or a seal to hold a lock between the body of the syringe and the face of the socket 87. After depressing of the lever L for opening the inlet end of the conduit 5 becomes the plunger of the syringe depressed to air - and if necessary a flushing solution - back through the line to press. The lever is then released, the syringe is removed and a new one The evacuated container is inserted into the socket 87. When the constipation condition is not eliminated by the above procedure, the assembly of the centering rings 37, 37A and membrane M are quickly and easily removed and replaced as a unit will. To this end, the screw 50 is loosened, which allows the electrode El to remove and thereby the one-piece hole arrangement unit U out of its position between the sensing electrodes. A new punching unit is in place the old one is inserted and the electrode Ei is returned to its original position. This unit is self-centering, which is important for accurate alignment ensure, especially if the line 5 is very narrow, which is a portable device should be the case. The screw 50, which acts as a jig is then tightened to restore a liquid-tight arrangement.

An important advantage of the device according to the invention is that that the line, except in use, with a hemolyzing, bacteriostatic and bungistatic or bactericidal and fungicidal solution completely can be kept filled. The fluid system can thus be kept closed, the valve V being closed when not in use.

According to Fig. 5, a rechargeable vacuum source or "thumb pump", generally designated 91, an inlet 93, which is at the outlet end 85 of the Line 5 is releasably attached. The thumb pump is in place of the evacuated container 81 can be used as a drive source to suck a sample through the line 5, and it also picks up the sample sucked through the line and allows to easily and safely dispose of the material collected in it. The pump has one Cylinder 95, one end of which communicates with the pump inlet, and a piston 97 slidable within the cylinder. An O-ring 99 is around the Piston attached and forms a sliding seal between the piston and the cylinder. The piston is hollow and covered by a plug 101. The piston is from a retracted position (the position shown in solid lines in Fig. 5) to a retracted position (that shown in FIG. 5 with dashed lines Position) movable when on the end of the piston provided with the plug of Hand pressure is being applied. This movement actuates the pump, and one Spring 103, which is located in the cylinder, biases the piston in its retracted Position before. A chamber 15 is formed by the piston and the cylinder. A Passage 17 provides a connection between the hollow part of the piston and the Chamber here.

A ball check valve 109 closes one end of the passage 107 and consists of a sphere iii which passes through one in the hollow part of the piston arranged spring 115 is pressed against an O-ring 113. During the initial stroke of the piston, when the pump is filled, the check valve 109 is pushed open and air and sample material previously sucked through the conduit pushed through passage 107 into the piston. A small amount of fluid can however, be pushed back by the conduit and the diaphragm assembly to prevent the Flush the fluid flow system, the valve V then being briefly opened.

This frees the line from obstacles again and from clogging prevented. A partial vacuum is generated in the chamber 105 as a result of the filling process and the resulting negative pressure serves as a drive source for sucking through a Sample through the line when the manually operated valve V is opened thereafter. After a number of fills, the piston 97 is with any collected sample material filled. If so, the pump 91 is removed from its position and upside down over a suitable waste container. Two drainage channels 117, which in the Plugs 101 are formed, stand with the hollow piston and with the atmosphere Link. The collected sample material flows through these drainage channels into the Waste container and after emptying the contents of the piston, the pump is again installed and used for the next particle counting process.

The pump 91 has several advantages over the evacuated container or the vacuum source ii because it can be recharged while in the meter is installed and. because their fluid reservoirs are easily emptied can, by simply turning the pump over. In addition, several samples can be counted, before evacuation is required because air is vented through drainage channels 117 when liquid builds up in chamber 105. Besides, it has has been shown that by flushing with counterpressure, which over the line 5 is applied to the hole A, the risk of clogging compared to the use of the pre-evacuated container 11 is reduced under the same conditions.

6, 7 and 8 is a second embodiment of a particle counter according to the invention designated as a whole with 1 'and has a shaft W' in which a sample is introduced, as well as a line 5 'through which the sample is drawn off to be collected in the pump 91. It is a thumb pump in FIG. 6 shown as a vacuum source, but it is clear that an evacuated container 81 can be used to aspirate and collect sample material. Samples flow through the line 5 'and one after the other to the measuring electrodes E4', E3 ' the sensing electrode E2 'and then through a hole A' in a membrane M 'which is arranged between the electrodes, and finally at the sensor electrode Ei ' past. The electrodes E1 and E2 'are therefore located downstream of the measuring electrodes E4 'and E3'. A flow regulator 119 is inserted in line 5 'to control the flow of a sample between the inlet end 9 'of the line and the pump 91. Of the Bottom of the shaft W 'is a flexible plate 15', which is made up by a lever L1 a position in which the line is closed, in a position in which the Line is open, can be moved when a button K1 is at one end of the lever being depressed.

7 and 8, the shaft W 'is in a block 118 of a Resin material such as that from E. I.

du Pont de Nemours & Co. under the trademark "Lucite", formed and the plate 15 'made of a suitable elastomeric material such as Rubber that is made is attached to the bottom of the block along its edges and forms the bottom of the shaft. A plate 120 has three fingers 121A-121C and openings OP are in the. Plate formed and used to attach the plate on the underside of the block 118 by screws 122 and spacers 123. Threaded holes (not shown) are in the bottom of the block 118 in coverage with the Openings OP for receiving screws 122 are formed. When the plate on the block 118 is attached, fingers 121A-121C protrude outward and each finger is as a cantilevered lever around an axis of rotation indicated by the dashed line P 'is shown movable. The finger 121A has an in-line opening 124A with the inlet end 9 'of the line 5'. A pin 125A has one end at the bottom of plate 15 'and protrudes through opening 124A. An enlarged Head 126A of the pen is spaced below the bottom of finger 121A and is moved downward when the K1 key is depressed. A Spacer 127A fits over the shaft of the pin. The finger 121A has a second Opening 129A between opening 124A and its free end. In line with A threaded hole 130A is formed in block 118 of opening 129A. One cone 131A is screwed into bore 130A and protrudes through opening 129A, so that part of the peg extends under finger 121A. A spring 133A is supported by the shaft portion of the pin 131A below the finger and exerts a compressive force between the bottom of the finger and a seat that consists of a washer 134A, which is fixed on the pin 131A by a nut 135A is held. The pushing force directed upward against the underside of the lever 121A this spring is activated by rotating the pin 131A clockwise or counterclockwise set. The post 121A has a slotted top end for receiving a Screwdriver with which the pin is turned. The K1 key is on the attached free end of the finger 121A. For this purpose, the free end of the Finger opening 138A. The complete arrangement forms a valve V1 for Open the inlet end of the line 5 'to allow a sample from the well W' through the pipe is sucked. A lever L1 of the valve consists of the finger 121A and, when the key Kl is depressed manually, the finger 121A becomes against the force the spring 133A moves downwards, whereby the pin 125A moves and the plate 15 ' is bent away from the inlet end of the conduit. A switch 19 '(Fig.

7) is arranged below the lever L1 and the actuator 21 'of the switch is detected by the lever when it moves downwards, to close the switch and reset the counter, so the counter count particles the next time a sample is passed through the conduit.

The line 5 'can be ventilated to the atmosphere to prevent the flow interrupt a sample through the line.

An opening or channel 137 (Fig. 6) is in the bottom of the Line formed and a sealing pad 139 (Figs. 6 and 8) for the opening 137 is attached to a lever L2 of a valve V2 and is used for opening and closing the opening 137. The lever L2 consists of the finger 12113 the Plate 120. This finger has an opening 129B at a location similar to that of FIG Opening 129A in finger 121A. A pin 131B, a spring 133B, a washer 134B and nut 135B are in the manner described above for valve V1 assembled and a key K2 is attached to the free end of the finger 121B. When the lever L2 is in the position in which it closes the opening 137, presses the pad 139 against the opening 137 and closes it. When the lever L2 is depressed by manually exerting a force on the K2 button, the finger 121B is moved against the force of the spring 133B and the pad 139 becomes moved away from port 137 to open the line to atmospheric pressure. Air is then drawn into the conduit and the flow of the sample upstream of the Opening 137 ends. This continues until the button K2 is released and the opening 137 is closed again. The remainder of the sample flows through the line and an air plug separates the two parts of the sample. The sequence described above can be repeated until all of the sample in the well is drawn into the line has been.

As a result, multiple sample parts can be obtained from a single sample sucked and a particle count can be carried out for each sample part.

To obtain a particle count for each part of the sample is the reset switch 19 'is arranged below the lever L2 and an on / off switch 141 (FIG. 9) is arranged below the lever L1. The switch 141 is also a microswitch and has an actuator that is detected by the lever L1 and is depressed when the lever is depressed. The lever also has L1 a Locking finger (not shown) by a Latch ~ (also not shown) is detected when the lever is depressed to keep the lever depressed and the on / off switch activated. There by depressing the lever L1 the inlet end of the line 5 'is opened, the sample is sucked from the shaft W 'into and through the line. When the front Part of the sample is visible at the base of the thumb pump 91, the K2 key is depressed, to open port 137 and draw air into the conduit. At the same time will the reset switch 19 'is actuated and the counting circuit 13 is reset. If the front edge of the air plug (the rear edge of the sample) the measuring electrode E4 ' leaves, the counting circuit 13 begins in the manner described above with counting particles. When the front edge of the air plug (the rear end the sample) passes the other measuring electrode and leaves it, the counting becomes of particles is ended and the particle count is displayed on the display unit 73 '. When the button K2 is released, the lever L2 returns to its original position back, port 137 is closed and the sample in line 5 'upstream this opening resumes the flow through the line. When the line 5 'is ventilated again, the counting circuit is released and blocked for the particle count again at the front edge of the introduced into the line Air plug leaving the electrode E4 'or E3'. If the line doesn't come back is ventilated, the actuation of the counting circuit 13 takes place at the rear edge the rest of the sample leaving the measuring electrodes.

After the entire sample has been sucked out of the shaft W ', the lever L1 is released by releasing its latch and the lever returns to his normal position back. The on / off switch 141 is inactivated by this operation and power to the metering and display circuit is turned off.

After a sample has been sucked out of the shaft, a Rinsing solution can be introduced into the shaft to rinse it. The rinse solution will sucked out of the shaft via a line 143 (Fig. 6) which has an inlet end 745 which is normally closed in the same manner as the inlet end of the line 5t i.e. the inlet end of this second conduit extends downwardly into the well W 'to the bottom of the well and the inlet end is fixed during the Bottom of the well, i.e. the flexible plate, relative to the inlet end of a Line closing position is movable into a line opening position. The drive source for sucking off rinsing solution through this second line is the pump 91, and the Outlet ends of the lines 5 'and 143 jointly open into a conical hole or a socket 147 in which the inlet end of the pump 91 or an evacuated container 81 (when a tube 85 and a socket 87 are provided) is received. That Opening of the inlet end of conduit 143 occurs in the same manner as opening of the inlet end of the conduit 5 ', i.e. a lever L3 having the same structure as the Lever L1 described above is movable about the axis of rotation, if a manual one Force is exerted on a button K3 at the free end of the lever. When the lever is depressed, the plate is bent downward and thereby the inlet end the line open. After the pocket solution has been sucked out of the shaft, the button K3 is released and the lever returns to its original position. The flexible plate pushes again towards the inlet end of the line and lock it.

Fig. 9 shows the circuit diagram of a second embodiment of the particle counting and display circuit for a particle counter according to the invention. This embodiment contains a computer chip 148 capable of performing mathematical operations, and a memory for storing usable data and the results thereof Operations. A keyboard 149 has several data and command keys DO-D19 on the means by which data and operating commands are fed to the computer chip, as for example in "The Small Electronic Calculator", Eugene W. McWhorter, Scientific American, March 1976, pp. 88-98.

The measuring and sensing parts of the counting circuit have the same structure as described above with reference to FIG. 4, with the exception that the measuring electrodes E3 'and E4' are arranged upstream of the sensing electrodes Ei 'and E2'.

The electrode E4 'is directly connected to the battery 47' when the switch 141 is closed while the electrode E3 'is connected to the battery a resistor R14 'is connected. The electrode E2 'is connected to ground and the electrode El 'is connected to the battery via a resistor R1' and the switch 141 and with connected to amplifier 55 'through a resistor R2'. The operation of the sensing and measuring electrodes is similar to that described above, the elements of the first Counting signal can be generated at the electrode El '. The elements of a first count signal are fed to the scaler 67 ', which is an element of the second count signal for every predetermined number of, for example 128, first signal elements generated, the him can be supplied by the comparator 63 '. The coaster 67 'is enabled by a signal with the value L from the NAND circuit G4', when the output of the comparator 77 'is high, which is the case is when the rear end of a sample leaves the measuring electrode E4 '.

The elements of the second count signal are an input of a bilateral Switch SW1, which is contained on an IS chip 151 (where IS is an abbreviation stands for integrated circuit). The chip 151 is, for example, that of the company. Solid State Scientific Inc., Montgomeryville, Pennsylvania, V.St.A. Model SCL 4016A and contains four double-sided switches, each of which has two input terminals and has an output terminal. The output of the comparator 77 is also to an input of a second bilateral switch SW2, which is on the chip 151 is included, applied via the RC element, which consists of a resistor R16 'and a Capacitor C6 'exists, and to the reset input of a decade counter 153. The Decade counter is supplied with clock pulses by a binary counter 155, which is controlled by a scanning signal from the computer chip 148. The decade counter 153 gives an output to one input terminal of each of four bilateral Switches SW3-SW6 contained on an IC chip 157 that are the same Structure like the chip 151 and is sold by the same company. The decade counter 153 is also commercially available from Solid State Scientific Inc., Montgomeryville, Pennsylvania, available under their model designation SCL 4017, as well as the Binary counter 155 under its model name 4040A. The use of the two-sided Switches on chips 151 and 157, decade counter 153 and binary counter 155 allows commands controlled by certain keys of the keyboard 149 to be carried out automatically as well as manually generated and fed to the computer chip 148 and thereby the control arithmetic operations carried out by the computer chip. will.

In particular, a bilateral switch SW7 and a bilateral switch control Switch SW1 on the chip 151 "delete" - or. "+ '^ - commands to the computer chip. The Switch SW2 controls the number "1". The two-sided switches SW3 -SW6 on the chip # 157 control "%" -, "#" -, ~ RCL "- resp.

"=" Commands to the computer chip. Every switch on every chip has as an input signal, a sampling signal supplied by the computer chip. The other input to the "erase" switch SW7 on chip 151 is to the Output of the RC element 71 'connected. The second input from each of the switches is on the chip 157 is connected to one of the output terminals of the decade counter 153 from below related reasons. The output from each switch is on both chips connected to an input of the computer chip 148.

It is sometimes desirable, for example, to do a particle count a sample of a reference cell suspension, i.e. a suspension that contains a known amount of particles per given volume before a particle count is carried out on other samples. With the particle counting circuit of FIG easily calculate a conversion factor for the reference suspension, which then is used to calculate the actual particle count of later samples. If, for example, the nominal value for the reference cell suspension is 4.55 million red blood cells per microliter, the value is 4.55 in the storage part of chip 148 by sequentially pressing keys D4 and D11, pressing twice the button D5 and then pressing the "Save" key D16 entered.

The reference cell suspension is then placed in an isotonic saline solution, for example in a ratio of about 1:50,000, diluted and a sample the diluted suspension is introduced into the shaft W '.

When the lever L of the manually operated valve V is depressed is to open the inlet end of the line 5, the reset switch 19 is operated and temporarily a high signal from the RC network 71 'is applied to an input of the double-sided switch SW7 on the chip 151 is applied. When the other input of the Switch SW7 is scanned by the computer chip, the switch sets an erase signal to the chip to clear the contents of its counting register. If the rear When the reference sample leaves the measuring electrode E4 ', the output signal of the Comparator 77 'has an H value, as explained above, whereby the coaster 67' released and temporarily an input signal of the switch SW2 to an H value and a 1 is entered into the computer.

The divider 67 'supplies a signal element of a second counting signal for each 128 signal elements of the first count signal supplied to it. Every signal element of the second count signal is applied to an input of the bilateral switch SW1 and when the other input of switches SW1 and SW2 is sampled by computer chip 148 the internal register in the chip is increased by 1. When the rear end of the Reference sample leaves the measuring electrode E3 ', takes the output signal of the comparator 77 'to an L value, whereby the reducer 67' is prevented from receiving further signal elements of the second counting signal. It continues through the H-to-L signal value transition the Dlekade counter 153 is reset at the comparator output.

The decade counter 153 responds, as mentioned, to clock pulses, which the binary counter 155 delivers in response to scanning signals which it delivers from the computer chip 148 receives.

When the contents of the decade counter reach ~ 2 ", a signal is given with the value H through the decade counter to an input of the two-sided switch 5D3 delivered on chip 157. If the other input of switch 5W3 is through the computer chip is scanned, a "%" command is issued to the computer chip. When the contents of the decade counter reach "4", a signal with the value H output to one input of the double-sided switch 5W4 and, if the other Input of the switch is scanned, a ~ + ~ command is issued to the computer chip. If the contents of the decade counter are ~ 6 "resp.

~ 8 ", an" RCL (retrieval) ~ or a "=" command is sent to the Computer chip delivered. Calls on the sequentially delivered group of commands the computer chip reads the reference value 4.55 stored in its memory. The number of counted second signal elements, multiplied by the factor O, OD, is given by divide this number and the result will be displayed if, for example, the counted Number of signal elements of the second counting signal would be 366, 0.8043956 was displayed will. This value, which is a conversion factor, is Now entered into the computer chip memory by pressing the D16 key, the "Save" function of the computer and labeled "CAL" to its calibration function to specify.

Particle counts for any number of additional samples can now be performed where the displayed particle count equals the number of signal elements the second Count signal is that are counted divided by the conversion factor stored in the computer chip memory. The mode of operation of the particle counter is the same as that described above, since the signal elements of the second count signal generated by the scaler 67 'when a sample is through the line 5 flows, and there the number of these signal elements through the computer chip 148 is counted. When the rear end of a sample leaves the measuring electrode E3 ', the coaster 67 'is blocked and the decade counter 153 is reset. the The sequence of commands described above is then generated and that in the computer chip memory The saved conversion factor is called up and the count is divided by it and the result is displayed. Thus, in the present example, if 421 Signal elements of the second counting signal are counted in a later sample, this number automatically by the previously saved conversion factor 0.8043956 divided and the result is displayed as 5.23 million cells per microliter. The same conversion factor remains in the computer chip memory until the power is applied of the counter is switched off or the memory is cleared. This calibration factor can re-entered into memory or entered manually as a divisor, when the meter is used again.

By using the particle counting circuit of Fig. 9 in that described above The measuring system of particle counters according to the invention can go from unit to unit vary slightly without affecting the accuracy of the actual particle counts, that are achieved with each unit. Furthermore, the dilution of each sample needs for which a particle count is carried out, no particular one value as long as the reference cell suspension used to calibrate the counter is in is diluted to the same extent as the samples later counted by a counter. This allows samples to be diluted using a simple, uncalibrated pipette, provided that the same pipette is used to dilute the reference cell suspension and each sample subsequently counted by the same counter is used.

In the embodiment of Fig. 9 and in the device of Fig. 6, as described above, the measuring electrodes E3 ', E4' upstream of the sensing electrodes E1 ', E2' arranged. Several advantages are achieved by this arrangement.

When the measuring electrodes E3 ', E4' on the low pressure side of the hole placed in the counting system and if there is any tendency to bubble exists, this will affect the liquid fronts, for example, and this is because the hole itself is usually the cause of the formation of bubbles. Since the measuring system is arranged upstream of the hole, there are caused by the hole There are no bubbles in the measuring system. If the rear end of the sample - instead of the leading edge-the control circuit triggers when the sensing electrodes are upstream the counting electrodes are, there is therefore perfect conductivity triggering the control circuit and therefore a more accurate volume measurement result. Also will the rate of flow through hole A during the counting period stabilized by the fact that as the column of liquid decreases in length, when the rear end moves from electrode E4 'to electrode E3' (counting period), the force needed to pull them decreases as there is less friction between of the liquid and the inside of the line 5 'occurs when the liquid column gets shorter while at the same time the pressure is at Using a pre-evacuated tube 81 decreases as more liquid increases as the count progresses enters tube 81. These two effects therefore contribute to that during the counting period makes the flow more stable and even than downstream of the Hole arranged measuring system is. There can therefore be a steady flow during the counting period can be achieved without the use of a flow regulator if required.

Claims (1)

Claims: oil device for counting particles, such as flake cells, which are suspended in a liquid medium, characterized by: a chamber (3) for taking a sample of the liquid medium containing suspended particles; a conduit (5) through which the sample can flow out of the chamber; a device (V) which normally closes the line and allows the line to flow through can be opened; a device (11) for sucking the sample through the Line at the same time as opening the line closing device (V); means (13) for counting particles in the sample as they pass through the Line flows; and a manually operable device (K) for opening the line closure device for the flow of a pipe and for the simultaneous actuation of the counter, so that the particles in the sample flowing through the conduit are counted. 2. Apparatus according to claim 1, characterized in that the suction device (11) is a vacuum source. 3. Apparatus according to claim 2, characterized in that the vacuum source is an evacuated container (8 #) to which the line (5) is connected and which picks up the aspirated sample after counting the particles. 4. Device according to one of claims 1 to 3, characterized in that that the chamber (3) has the shape of a shaft (W) for receiving the sample is open at the top and also has a bottom (B), and that the line (5) has an inlet end (9) which extends down into the shaft to its bottom extends with the bottom of the manhole and the inlet end of the conduit between a closed position in which the bottom closes the inlet end, and an open position in which the inlet end and the bottom are mutual Have a distance so that the sample can penetrate the line, are relatively movable. Apparatus according to claim 4, characterized in that the inlet end t9) of the line (5) is fixed and that the bottom (B) of the shaft (w) is flexible and from the conduit closed position in which it is at the inlet end of the conduit is bendable into the line opening position. 5. Apparatus according to claim 5, characterized in that the bottom (B) of the shaft (W) has a flexible plate (157 and that the manually operated Device has a Dinriclatung (L) znin bending of the plate. 7. Apparatus according to claim 6, characterized in that the bending device a lever (L) for bending the plate (15) to the conduit opening position when exercised having a manual force on one end thereof and that a spring (17) den Lever pretensioned in the line closed position. 8. Apparatus according to claim 7, characterized in that the counting device (13) has a switch (19) which can be actuated by the lever (L) when the plate (15) is moved to the conduit opening position to the counter reset so that it will be able to pick up the particles in the next to count sample flowing through line (5). 9. Apparatus according to claim 8, characterized in that the counting device (13) has a circuit arrangement, which the switch (19) only then current feeds when it is actuated by the plate (15) when this is in its line opening position is located. 10. Device according to one of claims 2 to 9, characterized in that that the line (5) has an outlet end (85) and that the vacuum source is a pump (91) which has an inlet (93) attachable to the outlet end. 11. Apparatus according to claim 1, characterized in that the pump (9 #) a cylinder (95) one end of which communicates with the pump inlet (93) stands, a piston (97) which is in the cylinder between a retracted position and a retracted position is slidable, and a manually operable Has device (ion) by means of which the piston from the retracted position is movable to the retracted position to operate the pump. 12. Apparatus according to claim 11, characterized in that by the Cylinder (95) and the piston (97) a second chamber (ios) is formed, which with a check valve (109) is provided which opens when the pump (91) is actuated to vent Lf from the second chamber to the atmosphere. 13. Apparatus according to claim 12, characterized in that the pump (91) has a spring (103) which moves the piston (97) into its retracted position biased when the manually operable device (101) is released, whereby a vacuum is created in the second chamber (105) to remove the sample through the conduit (5) to suck when the line closing device (V) is open, with the through the line sucked sample is collected in the second chamber. 14. Apparatus according to claim 13, characterized in that the piston (97) is hollow and has a first passage (107) which communicates with the second chamber (105) communicates, and a second passage (117) that communicates with the atmosphere communicates with the check valve (109) at one end of the first passage (107) is arranged, whereby a sample collected in the second chamber through the first passage in the piston is admitted when the pump (91) actuates is, and is discharged from the piston via the second passage (117) when the Pump is turned over. 15. Device according to one of claims 1 to 14, characterized by manually operated devices (137, 139) for opening the line (5 ') opposite the atmosphere to stop the flow of the sample in the line. 16. Apparatus according to claim 15, characterized in that the ventilation devices (137, 139) an opening (137) for the line (5 ') and a device (139) for have optional opening and closing of the opening. 17. Apparatus according to claim 16, characterized in that the opening (137) consists of a hole in the line (5 ') and that the opening and closing device a shutter (139) for the hole, which is supported by a lever (L2) which moves the shutter away from the hole to an open position when a manual force is applied to one end of the lever and from a spring (133B), which biases the lever in an opening-closing position in which the shutter covered the hole. 18. Apparatus according to claim 17, characterized in that the counting device (13) has a switch (19 ') which can be actuated by the lever (L2) when the shutter (139) is moved to the opening position of the opening 137 to the Reset counter, so that by successive manual operations of the lever successive air plugs are introduced into the line (5 '), to divide the sample flowing therein into successive parts, wherein the counter # each time the switch is actuated by the movement of the lever is reset to count particles in each part of the sample. 19. Device according to one of claims 1 to 18, characterized by a device (143, Fig. 6) for dispensing a washing solution from the chamber (3), wherein the wash solution is introduced into the chamber after a sample has been removed from the Chamber has been sucked off via line 5 '. 20. Apparatus according to claim 19, characterized in that the chamber (3) consists of a shaft (W ') which is open at the top and has a bottom, and that the dispensing device (143, Fig. 6) has a second line (143) over which sucks the washing solution out of the shaft (W ') through the suction device (11; 91) with the second conduit (143) having an inlet end (145) that extends downward extends into the shaft to its bottom, and that the bottom of the shaft and the inlet end of the second conduit between a closed position in which the Bottom closes the inlet end, and an opening position in which the inlet end and the bottom have mutual spacing to allow the washing solution to enter the second management can penetrate, are relatively movable. 21. Apparatus according to claim 20, characterized in that the inlet end (145} of the second line (143) it is certain that the bottom (B) of the shaft (W ') a flexible plate (is') - and that the manually operated device is a Lever. (L3) has to bend the plate into the line opening position when a manual force is applied to one end (K3) of the lever, and a spring (133C), which biases the lever into the line closed position. 22. Device according to one of claims 1 to 21, characterized in that that the counting device (13) contains a particle detector (23) for determining of particles in the sample as it flows through the line (5) and for generating an electrical signal indicative of the detected particles. 23. Apparatus according to claim 22, characterized in that the medium, in which the particles are suspended, is electrically conductive, and that the particle detector (23) means for closing an electrical circuit across the sample, when this flows through the line (5), the conductivity of the circuit is changed by particles in the sample to generate the electrical signal. 24. Apparatus according to claim 23, characterized in that the line (5) has an inlet end (9) and that the particle detector (23) has two electrodes (Ei, E2) located downstream from the inlet end, at each electrode allowing the sample to flow past and each electrode having an electrical power source (47) is connectable, whereby the electrical circuit between the electrodes is closed over the sample when it flows past both electrodes at the same time, and an electrically non-conductive part (M), which is between the electrodes (Ei, E9) is arranged and has a hole (A) which is dimensioned so that particles in the sample can pass through it, the passage of a particle through the hole temporarily the conductivity of the electrical circuit between influences the electrodes and generates a signal element of the electrical signal. 25. Apparatus according to claim 24, characterized in that the counting device (13) a circuit (53) for amplifying the generated by the particle detector (23) Signal elements and a circuit (63) for comparing the amplitude of each amplified Signal element with a predetermined reference value, the amplitude of which depends on the size the particle in the sample is dependent on which are to be counted to an element of a Generate counting signal for each amplified signal element that contains the reference value exceeds, has. 26. Apparatus according to claim 25, characterized in that the counting device (13) a counting circuit (68) for counting the number of count signal elements generated contains, where the content of the counting circuit depends on the number of particles in the sample, which exceed a predetermined minimum size, is dependent. 27. Apparatus according to claim 26, characterized in that the counting device (13) contains a scale (27) for counting those generated by the comparator (63) Elements of the counting signal and for outputting an element of a second counting signal to the counting circuit (68? for every predetermined number of counting signal elements counted, the content of the counting circuit being equal to the number of elements delivered to it of the second count signal. 28. Device according to one of claims 24-27, characterized in that that the part (M) has a membrane and devices (37, 37A) for releasable Attach the electrically non-conductive membrane between the electrodes (E1 E2), so that the diaphragm can be replaced if its hole (A) becomes blocked or damaged will. 29. Apparatus according to claim 28, characterized in that the devices (37, 37A) for releasably securing the electrically non-conductive membrane (M) between the electrodes (Ei, E2) comprise centering devices with the opposite Surfaces of the membrane are glued together, creating the membrane and the centering devices can be removed and replaced as a unit that is self-centering. 30. Apparatus according to claim 29, characterized in that the centering devices Centering members (37, 37A) which correspond to each of the two opposing surfaces the membrane (M) are glued and each have a passage that a first connector (25) is provided which has a passage connected to the inlet end (9) the line (5) is in communication that a second connector (25A) is provided communicating with the outlet end of the conduit, the fittings are relatively movable towards and away from one another, that a device (50) to clamp the membrane (M) and the parts glued to it between the Fittings as a one-piece arrangement by moving the fittings towards one another (25, 25A) is provided, and that the connecting pieces and the centering parts mate Have configurations, eliminating the parts when they are between the fittings are clamped, are arranged so that the passages in the connecting pieces and in the centering parts (37, 37A) all communicate with the hole (A). 31. Apparatus according to claim 30, characterized in that the connecting pieces (25, 25A) each contain one of the electrodes (Ei, E2). 32. Apparatus according to claim 31, characterized in that the connecting pieces (25, 25A) form the electrodes (Ei, E2) and that the axes of the passages in the Connection pieces and the centering parts (37, 37A) coaxially in line with the Hole (A) are arranged. 33. Apparatus according to claim 32, characterized in that the centering parts (37, 37A) have an annular shape and that the electrodes (El, E2) are cylindrical are, the internal dimensions of the passages in the centering parts only slightly are larger than the external dimensions of the electrodes, which makes the one-piece arrangement easily exchanged from the membrane and the parts glued to it will can when the fittings 25, 25A moved away from each other and after moving together the connecting pieces are self-centered when they are tightened again. 34. Device according to one of claims 1 to 33, characterized by a display unit (73) for displaying the number of particles passed by the counter (13) have been counted, in the form of a visual display of the number of particles. 35. Device according to one of claims 1 to 34, characterized in that that the counting device (13) means for forming a calibration factor and for Multiply the number of particles counted by the calibration factor to generate a number representative of the actual number of particles in the sample. 36. Apparatus according to claim 35, characterized in that the calibration devices means for generating a value equal to the number of particles in a predetermined volume of a reference sample contained in the Chamber (3) is received and sucked through the line (5), and a storage device to save this value. 37. Apparatus according to claim 36, characterized in that the storage device is contained on a computer chip (148) and that the means for generating the Value contains a keyboard (149) with several manually operable keys the numbers and operating commands are generated and sent to the chip, the value generated by pressing number keys on the keyboard and stored in the memory device by pressing a suitable command key will. 38. Apparatus according to claim 37, characterized in that the calibration devices a sequencer responsive to the completion of the counting of particles responds in the reference sample to retrieve the value from the storage device and divide the value into the actual number of particles for the reference sample and thereby generating the calibration factor which is then stored in the storage device the sequencer continues upon completion of counting of Particles in a sample later sucked through the line (5) responds to sequentially To issue command signals to the computer chip (48) in a sequence through which the Calibration factor retrieved from the storage device and the particle number for the sample is divided to thereby produce the number representing the actual number of particles is representative of the sample. 39. Apparatus according to claim 1, characterized in that the medium, in which the particles are suspended, electrically conductive and that further a measuring device for the precise determination of a sample volume which is equal to that, in which the particles are to be counted is provided which is a piece of the line (5) which is substantially electrically non-conductive, a first and a second electrode (E3 or E4) at a predetermined distance along the Line arranged to be sequentially touched by the sample when this passes through, a device which, when one end of the sample makes the first contact happened, initiates the counting of particles, and a device which, when the same end of the sample passes the second contact, counting particles ended, whereby the number of particles counted represents those which are contained in a sample volume that is equal to that in the Line piece is present between the electrodes. 40. Apparatus according to claim 39, characterized in that -the device means (77) for sensing for initiating and terminating the counting of particles a change in the conductivity of the circuit in the line piece between the first and second electrodes (E3, E4). 41. Apparatus according to claim 39, characterized in that the device contains a third electrode (E2) for initiating and terminating the counting of particles, which is touched by the sample and along the line section and next to the second Electrode (E3) is arranged, and a device for AbSüh'en changes in the conductivity between the first and the second electrode (E4, E3) and the conductivity between the second and the third electrode (E3, E2), whereby, When one end of the sample passes the first, second, and third electrodes, the conductivity of the paths between the first and the second and the second and of the third electrode changes sequentially and thereby a first control signal to initiate counting and a second control signal to terminate counting be generated. 42. Apparatus according to claim 41, characterized in that the first and second electrodes (E4, E3) upstream of the third electrode (E2) are arranged, with the rear end first the first, the second and the third Electrode happens in this order, whereby the first control signal is transmitted through the rear end of the sample is generated when it leaves the first electrode while the second control signal is generated when the trailing end of the sample passes the second Electrode leaves. 43. Apparatus according to claim 41, characterized in that the first and the second electrode (E4, E3) arranged downstream of the third electrode (E2) with the front end of the sample being the third, second and first electrodes happens in this order, whereby the first control signal is generated when the front end of the sample reaches the second electrode while the second control signal generated by the front end when it reaches the first electrode. 44. Device according to one of claims 1 to 43, characterized by a portable frame (F) in which the chamber (3), the line (5), the line closure device (V), the particle counting device (13) and manually operated devices (K) are attached and to which the suction device (11; 91) is releasably attached. 45. Device for counting particles, such as blood cells, that are present in an electric conductive liquid medium, characterized by: a chamber (3) for taking a sample of the liquid medium containing the suspended particles contains; a conduit (5) through which the sample leaves the chamber flows through; means (11; 91) for sucking the sample through the Management; means (13) for counting the number of particles in the sample when they are flows through the pipe; and a measuring device for the precise determination of a sample volume, which is equal to the one in which the particles are to be counted, with one piece the line (5), which is essentially electrically non-conductive, with a first and a second electrode (E4, E3) which are at a certain distance from each other are arranged along the conduit to sequentially pass through the sample to be contacted with a device (77, X1) which, when an end of the sample the first contact happens, initiates particle counting, and with a device (77, X2) that when the same end of the sample passes the second contact, the counting terminated by particles, whereby the number of particles counted represents those contained in a sample volume which is equal to that contained in the line piece between the electrodes (Es, E4) is included, the facilities means for sensing for initiating and terminating the counting of particles a change in the conductivity of the path in the line piece between the first and second electrodes and a third electrode (E2) included, which also is contacted by the sample, wherein the third electrode is along the line piece and arranged adjacent to the second electrode (E3), and means for sensing of changes in conductivity between the first and the second electrode and in conductivity between the second and the third Electrode, whereby if one end of the sample the first, the second and the third Happens to be the conductivity of the paths between the first and the electrode second and between the second and third electrodes sequentially changes and thereby generating a first control signal which initiates counting, and a second control signal which ends the counting, the first and the second Electrode upstream of the third electrode are arranged and the rear end first, second and third electrodes pass in this order, whereby the first control signal is generated by the rear end of the sample when this leaves the first electrode, and the second control signal is generated when the rear end of the sample leaves the second electrode. 46. Apparatus for counting particles, such as blood cells, that are present in an electrical conductive liquid medium, characterized by: a chamber (3) for taking a sample of the liquid medium containing the suspended particles contains; a conduit (5) through which the sample flows from the chamber; two Electrodes (Ei, E2) arranged downstream of the inlet end (9) of the line which the sample flows past and which are connected to an electrical power source (47) can be connected, creating an electrical circuit between the electrodes about the sample is closed when these at the same time on both Electrodes flowing past; an electrically non-conductive membrane (M) between the electrodes is arranged and has a hole (A) which is dimensioned so that Particles in the sample can pass through, with the passage of a particle through the hole temporarily the conductivity of the electrical circuit between influences the electrodes and generates a signal element of an electrical signal, which indicates the number of particles to be counted; a device (11; 91) for sucking through the sample through the pipe and the hole; Centering parts (37, 37A), which with the two opposite surfaces of the membrane (M) are glued and have a passage; a first fitting (25) having a passage which connects to the inlet end (9) the line is in communication, and a second connector (25A) with communicates with the outlet end of the conduit with the fittings on one another are relatively movable to and away from each other; and a device (50) for clamping together the membrane and the parts bonded to it as an integral arrangement between the connecting pieces by moving the connecting pieces on one of the connecting pieces, whereby the connecting pieces and the centering parts have mating configurations whereby the parts, when they are clamped between the connectors, are arranged so that the passages in the connecting pieces and the centering parts all communicate with the hole. 47. Apparatus according to claim 46, characterized in that the connecting pieces (25, 25A) each have one of the electrodes (El, E2). 48. Apparatus according to claim 46, characterized in that the connecting pieces (25, 25A) form the electrodes (Ei, E2j) and that the axes of the passages in the connecting pieces and arranged in the centering parts (37, 37A) coaxially in line with the hole (A!) are. 49. Apparatus according to claim 48, characterized in that the centering parts (37, 37A) have an annular shape and that the electrodes (Ei, E2) are cylindrical are, the internal dimensions of the passages in the centering parts only slightly are larger than the outer dimensions of the electrode, creating the one-piece arrangement can easily be exchanged from the membrane and the parts glued to it, when the connectors (25, 25A) are moved away from each other and after the connectors are moved together during reclamping, become self-centered. 50. Method of counting particles, such as blood cells, present in a liquid medium are suspended, characterized by the following steps: Introducing a first sample of the liquid medium containing a known amount of particles in containing a predetermined volume into a chamber; Sucking the First sample from the chamber through a conduit and count the particles in the first Sample when it flows through the conduit; Divide the number in the first Sample counted particles by a number that is equal to the known amount thereby generating a calibration factor; Introducing a second sample of a liquid Medium containing an unknown amount of particles into the chamber and suction this sample by guiding and counting the particles in the second sample when this flows through the pipe; and dividing the number of in the second sample counted particles by the calibration factor to produce a number that is the actual Represents particle number for the second sample.