JPS58129347A - Counting device for fine particle - Google Patents

Abstract

PURPOSE:To prevent choking of a pore, by a method wherein, in a Coulter counter, a piezo-electric vibrator is loated to a peripheral part of a pore. CONSTITUTION:With a pressure reducing pump 7 started, silver surfaces of a manometer 8 are deflected by a suction action, and a sample liquid 22 in a beaker 23 is fed in a blood cell detecting cell 2 and a pressure reducing pipe 5. A cock 6 is then closed, and a specified volume of the sample liquid 22 is further sucked in the cell 2 as a result of the movement of the silver surfaces. The sample liquid 22 passes through a pore 34a, and a blood cell 21 is detected as a pulse at a detecting circuit 11 by detecting electrodes 35a and 35b. If the pore 34a is choked, a monitoring device 17 detects it, and an AC magnetic field is applied to a piezo-electric vibrator 36 through lead wires 37a and 37b. This enables applying of a moving force to dusts clogging the pore 34a, flipping the dusts off, which results in eliminating choking.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a particle counting device, and more particularly, to a particle counting device that counts particles contained in a liquid, such as red blood cells and white blood cells contained in blood, through pores. .

A particle counting device that counts the number of particles contained in a liquid is already well known as, for example, a hematology cell counting device that counts the number of blood cells in blood. This type of conventional hematology analyzer is
For example, it was constructed as shown in FIG. That is, the conventional blood cell counting device includes a blood cell detection cell 2 made of a bottomed cylindrical body with a blood cell detection part 1 provided on the bottom wall, a manometer 4 made of a U-shaped tube containing mercury 3, and a blood cell detection cell 2 made of a U-shaped tube containing mercury 3. A decompression pipe 5 connecting the cell 2 and the manometer 4, a decompression pump 7 connected to the decompression pipe 5 via a watertight pipe, and a counting start electrode 8 and a counting stop electrode 9 which are connected to the manometer 4tcR. The main parts were composed.

The blood cell detection section 1 has a diameter of 100μ for allowing blood cells to pass through.
It is composed of an extremely small pore of about 2.0 m in size and a pair of detection electrodes installed near this pore, and changes in resistance or capacitance between the detection electrodes when blood cells pass through the pore. This is to detect. And, the above-mentioned detection electrode is
It is connected to a detection circuit 11 that converts a resistance change or capacitance change between the same electrodes into an electrical signal, and the output of the detection circuit 11 is amplified by an amplifier circuit 12 and input to a discrimination shaping circuit 13. There is. The discrimination shaping circuit 13 discriminates the input signal using upper and lower thresholds, shapes the waveform of only the signals between the upper and lower thresholds, and outputs the waveforms to the counting circuit 14 as count pulses. Since the magnitude of the input signal is proportional to the size of blood cells, this discrimination shaping circuit 13 selects only signals corresponding to blood cells with a size within a predetermined range and counts them. It is done for the sake of

The counting circuit 14 is a circuit for counting the number of blood cells by integrating the count pulses from the discrimination shaping circuit 13, and one of its control signal input terminals is connected to the counting start electrode 8. , are connected to the output ends of a start pulse/stop pulse generation circuit 15 whose other input ends are connected to the counting stop electrode 9, respectively. This start pulse/stop pulse generation circuit 15 generates a start pulse when the mercury 3 in the manometer 4 contacts the counting start electrode 8, and generates a stop pulse when the mercury 3 in the manometer 4 contacts the counting stop electrode 9. These pulses are applied to the counting circuit 14 to control the counting start time and counting stop time of the counting circuit 14.

The counting circuit 14 is connected to a display device 16, and the number of blood cells counted by the circuit 14 is displayed on the display device 1.
6 is now displayed. Further, the discrimination shaping circuit 13 is connected to a monitoring device 17 such as an oscilloscope, so that the waveform of the signal input to the circuit 13 can be monitored by the monitoring device 17.

In order to measure the number of blood cells per unit volume of blood, for example, the number of red blood cells, using a conventional blood cell counter with such a configuration, it is necessary to measure the number of red blood cells 21 with a size of about 7 to 8 μm in 1 mm cube. contains about 5 million pieces,
Since the number of blood cells cannot be counted as it is, first, the test blood is diluted to SOO times with a diluent such as physiological saline, and this is placed in a beaker 23 to be used as a blood cell sample liquid 22.

Next, the blood cell detection cell 2 is immersed in this blood cell sample liquid 22, the watertight cap is opened, and suction by the vacuum pump 7 is started. Then, the pressure inside the blood cell detection cell 2 and the manometer 4 is reduced through the pressure reducing tube 5, and the sample liquid = 2 gradually enters the blood cell detection cell 2 through the pores provided in the bottom wall, and at the same time enters the manometer 4. Decompression tube 5 containing mercury 3
One end of the wall gradually rises, and the other end of the open end descends. Finally, as shown in FIG. 1, the blood cell detection cell 2 and the pressure reducing tube 5 are filled with the sample liquid 22, and the other end surface of the mercury 3 is lower than the height of the counting start electrode 8. become. So, I closed the watertight cover and
Suction by the vacuum pump 7 is stopped.

When the watertight lid is closed, the equilibrium between the pressure applied to the surface of the sample liquid 22 and the pressure applied to the other end face of the mercury 3 is broken, and the other end face of the mercury 3 begins to rise to balance this. Therefore, the sample liquid 22 is gradually sucked from the beaker 23 into the blood cell detection cell 2 through the extremely small pores, and the blood cells 21 contained in the sample liquid 22 pass between the detection electrodes provided near the pores. pass one after another. Therefore, changes in resistance or capacitance occur one after another between the detection electrodes, which are detected by the detection circuit 11 and converted into a pulsed electrical signal. This electrical signal is amplified by an amplifier circuit 12, discriminated and waveform-shaped by a discrimination shaping circuit 13, and
The pulse is input to the counting circuit 14, but at the beginning of the rise of the other end surface of the mercury 3, the pulse is input from the pulse generating circuit 15 to the counting circuit 1.
Since the start pulse is not applied to the counter 4, counting in the counting circuit 14 has not started yet.

When the other end surface of the mercury 3 rises and contacts the counting start electrode 8, the pulse generating circuit 15 generates a start pulse in response to this and applies it to the counting circuit 14. Therefore, the counting circuit 14 starts counting the count pulses output from the discrimination shaping circuit 13. Then, when the other end surface of the mercury 3 further rises and contacts the counting stop electrode 9, the pulse generating circuit 15 generates a stop pulse in response to this, and the counting circuit 1
4. Therefore, the counting circuit 14 stops counting the count pulses output from the discrimination shaping circuit 13.

The amount of sample liquid 22 flowing from the beaker 23 into the blood cell detection cell 2 from when the other end surface of the mercury 3 contacts the counting start electrode 8 to when it contacts the counting stop electrode 9 is , which is equal to the volume of the manometer 4 between the position where it contacts the counting start electrode 8 and the position where it contacts the counting stop electrode 9, is a constant amount.

Therefore, the count number counted by the counting circuit 14 is:
It represents the number of blood cells contained in a certain volume of sample liquid 22. Therefore, by appropriately converting the count in the counting circuit 14, the number of blood cells per unit volume of blood is determined, and this value is displayed on the display device 161C. Note that even while the counting circuit 14 is counting, the monitoring device 17
It goes without saying that the waveform of the signal can be monitored by

The above is an overview of the conventional blood cell counting device. In the case of this device, the blood cell detection part l is formed by extremely small pores, so it is difficult to detect particles that are clogged with blood cells or dirt that gets mixed in along the way. The drawback is that the pores tend to become clogged, and when they become clogged, it is necessary to stop the measurement and remove the accumulated blood cells and dirt.

This removal work is difficult and troublesome because the pores are small, and has the disadvantage of significantly reducing the measurement efficiency of the device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a particle counting device in which a piezoelectric vibrator is provided around a pore in order to eliminate the above-mentioned conventional drawbacks.

Vibration is also applied to foreign objects such as blood cells and dirt that are stuck in the holes, so they can be broken down into small pieces,
It can also be thrown into and out of pores. Therefore, suction pressure from the manometer is also applied, and the clogging of the pores is eliminated. This eliminates the need for clogging removal work.
Since the measurement does not have to be stopped, the measurement efficiency of the device is significantly increased.

Hereinafter, the present invention will be explained based on illustrated embodiments.

FIG. 2 shows a particle detection cell 32 in a particle counter showing an embodiment of the present invention. This particulate detection cell 32 includes an outer cylinder 33 made of a glass tube, a plastic tube, etc., and a bottom plate 34 made of a glass plate, a plastic plate, etc. attached to the lower open end of the outer cylinder 33 so as to close the open end. And, there is a button perforated in the center of this bottom plate 34.
An extremely small pore 34'a of about 0/jm, and an opening 34'a on the bottom plate 34 near the pore 34a. A pair of detection electrodes 35a, 3 arranged so as to surround a.
5b and a donut-shaped piezoelectric vibrator 36 disposed on the bottom plate 34 so as to surround the detection electrodes 3sa and 3asb.

The piezoelectric vibrator 36 is a vibrator whose main vibration mode is bending vibration, and when an alternating current electric field having a frequency approximately equal to the natural frequency of the vibrator 36 is applied to a drive electrode (not shown), resonance occurs in the radial direction. The trap is designed to produce mechanical vibrations that cause the material to flex. The piezoelectric vibrator 36 is bonded to the bottom plate 34 using an epoxy resin adhesive or the like, and the vibrator 36 and the bottom plate 34 integrally form a piezoelectric vibrator. Since the periphery of the holder is fixed to the outer cylinder 33, the maximum displacement occurs in the periphery of the pore 34a.

In addition, the electrode of the piezoelectric vibrator 36 and the detection electrode 35a,
From 35b, a pair of insulating coated lead wires 37a
, 37b, 3sa, and 3sb are connected and drawn out, respectively. Further, an insulating layer 39 is provided on the piezoelectric vibrator 36 and the detection electrodes 35a, 35b to insulate them from the sample liquid 22. However, the opposing end surfaces of the detection electrodes 35a and 35b are exposed to the inner peripheral surface of the through hole of the insulating layer 39 that communicates with the pore 34a, so that the detection electrodes 35a and 35b are exposed to the inner circumferential surface of the through hole of the insulating layer 39 communicating with the pore 34a. It has become.

The other parts of the particle counting device of this example are as follows:
Since the structure is exactly the same as the conventional blood cell counting device shown in FIG. 1, a detailed explanation thereof will be omitted.

According to the particle counting device of this embodiment configured in this manner, the waveform of the detection signal is observed by the monitoring device 17 in FIG. If the lead ll1 is connected to the piezoelectric vibrator 36 by operating the operating member provided as appropriate,
An alternating current electric field of about 10 to 2 oov may be applied through I37a and 37b. In this way, piezoelectric vibrator 3
6 undergoes bending vibration, and the maximum displacement occurs near the pore 34a. This displacement applies a moving force to the clogged blood cells, dirt, etc. in the pore 34a, and by this moving force,
A collection of blood cells is broken apart, and dirt is trapped in pore 3.
4a, and the clogging is cleared. The degree of ease with which blood cell clusters, dust, etc. can be removed at this time depends on the amount of displacement and acceleration of the piezoelectric vibrator, and these depend on the thickness and diameter of the piezoelectric vibrator, the material constants of the piezoelectric vibrator, and the manometer. 4 (see Figure 1). For example, when the diameter of the piezoelectric vibrator is 10 mm, the thickness is 0.5 mm, and the driving voltage is a pulse voltage of 200 V, the amplitude near the pore 34a is approximately 10 μm.
The maximum amplitude was obtained when the pulse width was approximately 20 μsec.

FIG. 3 shows a particle detection cell 42 in a particle counter showing another embodiment of the present invention.

This particulate detection cell 42 includes an outer cylinder 43 made of a glass tube, a plastic tube, etc., and a bottom plate 44 made of a glass plate, a plastic plate, etc. attached to the lower open end of the outer cylinder 43 so as to cover the open end. And, an extremely small pore 44a of about 100 μm bored in the center of this bottom plate,
A pair of detection electrodes 45a and 45b are embedded in the bottom plate 44 facing each other so that their opposite end surfaces are exposed to the inner peripheral surface of the pore 44a, and an upper surface is formed at the lower opening edge of the pore 44a. The main part thereof is constituted by an annular piezoelectric vibrator 46 to which is pasted.

The piezoelectric vibrator 46 is a radially polarized vibrator whose main vibration mode is thickness vibration, and has a pair of drive electrodes (not shown) formed on its outer and inner circumferential surfaces. A pair of insulating coated lead wires 47a and 47b are connected and drawn out from the pair of drive electrodes. Furthermore, a pair of insulating coated lead wires 4sa and 4sb are connected and drawn out from the detection electrodes 45a and 45b. Furthermore, the area around the piezoelectric vibrator 46 is insulated by an insulating layer 49.

In the case of the particulate counting device of this embodiment, the other members are constructed in exactly the same manner as the conventional blood cell counting device shown in FIG. 1 above. Therefore, the detailed explanation will be omitted.

According to the particle counting device of this embodiment configured in this way, when the waveform of the detection signal is observed by the monitoring device 17 in FIG. Lead wire 47a.

A pulse voltage of 100 to 200 V is applied to the piezoelectric vibrator 46 through the piezoelectric vibrator 47b. Then, the thickness of the piezoelectric vibrator 46 in the radial direction changes, and the inner diameter of the piezoelectric vibrator 46 changes. Therefore, if the above-mentioned pulse voltage is made into an alternating current pulse of about several tens of KHz and driving with this pulse is repeated several times, the inner diameter of the pore 44a will change along with the vibration of the piezoelectric vibrator 46, and the pore 44a will become clogged. The garbage is manometer 4 (
(see FIG. 1) is sucked into the detection cell 42. Therefore, clogging of the pores 44a is eliminated.

In each of the above embodiments, when the user of the particle counter observes the detection signal waveform using the monitoring device and determines that the pores have become clogged, the user manually controls the piezoelectric vibrator. Although the explanation has been given in which a driving voltage is applied, it goes without saying that a monitoring circuit may be provided to automatically drive the piezoelectric vibrator.

Further, it goes without saying that the application of the particle counter of the present invention is not limited to the use of the blood cell counter shown in the conventional example.

As described above, according to the present invention, a piezoelectric vibrator is provided in the periphery of the pore, so that a particle counting device which is extremely convenient to use and which eliminates the conventional drawbacks mentioned in the specification can be provided. can be provided.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a blood cell counter, which is an example of a conventional particle counter. FIG. 2 is a sectional view of a main part of a detection cell in a particle counter, which is an embodiment of the present invention. FIG. 2 is a sectional view of a main part of a detection cell in a particle counting device showing another embodiment of the present invention. 32.42--1...Particle detection cell 3
4.44 @-...eII fist S bottom plate 34a#
44a...e・1-轡...Small pores 35a, 35b, 4
5a, 45b @-detection electrode 36.46...
...Continued from page 1 of piezoelectric vibrator 0 Author: Takuko Tachikawa, 2-43-2 Hatagaya, Shibuya-ku, Tokyo Lymphus Optical Industry Co., Ltd. 0 Author: Satsuki Kanbara 2, Hatagaya, Shibuya-ku, Tokyo 2-43-2, Lymphus Optical Industry Co., Ltd. Inventor: Michio Nawa, 2-43-2 Hatagaya, Shibuya-ku, Tokyo, Lymphus Optical Industry Co., Ltd.

Claims (1)

[Scope of Claims] A particle counting device that counts particles contained in a liquid through pores, wherein a piezoelectric vibrator is provided in the periphery of the pores to remove clogging of the pores. Characteristic particulate counting device.