JPS63100330A - Liquid level detector - Google Patents

Abstract

PURPOSE:To accurately detect the quantity of insertion of the lower end of a nozzle member into sample liquid by vibrating a nozzle member held by a vibration transmission plate at a specific frequency and detecting the extremal value of the output voltage or current of a vibration inducing means which varies when the lower end of the nozzle member contacts the liquid surface. CONSTITUTION:A sample container 52 is placed and a vibrator 34 is vibrated with a signal from a controller 90. A chip up/down control means 60 lowers a spot application chip 35 fitted atop of a spot application arm 30 together with the arm 30. When the lower end of the chip 35 contacts the liquid surface of the sample liquid in the container 52, the output voltage of the vibrator 34 varies. The extremal value of the varying voltage is detected to accurately detect the depth of the insertion.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a device for detecting the liquid level position of a sample liquid when the sample liquid in a container is sucked by a suction body. In particular, the present invention relates to a liquid level detection device that can be used for a device that automatically dispenses a fixed amount of sample liquid onto a chemical analysis slide (hereinafter simply referred to as slide) containing a predetermined reagent. It is.

(Prior Art) Qualitative or quantitative analysis of specific chemical components in a liquid sample is a commonly performed operation in various industrial fields. In particular, quantitative analysis of chemical components or formed components in biological body fluids such as blood and taste is extremely important in the biochemical and clinical fields.

In recent years, a dry type slide has been developed that allows quantitative analysis of specific chemical components or organic components contained in a sample solution by applying small droplets of the sample solution (C-tube). No. 53-21677, Japanese Patent Publication No. 55-16435
No. 6, etc.) has been put into practical use. These slides allow sample liquid analysis to be performed more easily and quickly than conventional wet analysis methods, so their use is particularly preferred in medical institutions, laboratories, etc. that need to analyze a large number of samples. It is something.

To analyze chemical components in a sample solution using such a slide, the sample solution is weighed onto the slide and then kept at a constant temperature (incubation) for a predetermined period of time in an incubator. The slide is then irradiated with measuring light containing a wavelength pre-selected based on the combination of sample components and reagents contained in the reagent layer of the slide to determine its reflected optical density. This is used to quantitatively analyze the chemical components mentioned above.

When performing such an analysis, a predetermined amount of the sample liquid must be precisely measured and applied to the reagent layer of the slide. This is because if the amount of the sample liquid is different from the predetermined amount, the reflected optical density will be different, and the above-mentioned analysis accuracy will also be lowered.

For this reason, divine pipettes and the like have been devised to ensure that a predetermined amount is not applied correctly when a sample liquid is dispensed.

Such a pipette is, for example, one in which a tip is attached to the tip of the pipette, and a predetermined amount of sample liquid is aspirated into the tip, and then this predetermined amount of sample liquid is dotted onto the sample surface of the slide. There is.

Many of these pipettes use a piston-cylinder mechanism to aspirate a predetermined amount of sample liquid into the tip and discharge it. To aspirate the sample liquid into the tip and discharge it into reagent 1 using such a pipette, first insert the tip tip into the sample liquid, and then add a predetermined amount into the tip using the side of the piston or cylinder. The sample liquid is sucked and held, and then the tip of the tip is positioned on the reagent layer of the slide, and the sample liquid in the tip is spotted and supplied onto the reagent layer using a piston-cylinder mechanism or the like. However, because
In this case, when the tip of the tip is inserted into the sample liquid and then pulled out for spotting, the sample liquid will adhere to the outer periphery of the tip, and this adhered sample liquid will also be spotted on the reagent layer. However, there is a problem in that errors occur in the sample paddy liquid that is applied, resulting in a decrease in measurement accuracy.

For this reason, in the past, the sample solution was aspirated into the tip using a pipette, and then the sample solution adhering to the outer periphery of the tip was wiped off before being dispensed spot-on. However, this method requires a wiping operation, which does not improve work efficiency, and when automatic spotting is performed, it is difficult to automate this wiping operation.

(Problem to be Solved by the Invention) For this reason, the present applicant has developed a method for inserting the tip of the tip into the sample liquid by controlling the vertical position of the tip and the sample liquid level when sucking the sample liquid into the tip. The amount of sample attached to the outer periphery of the tip is always kept constant, and the amount of sample attached to the tip tip is always constant. A dotting device was proposed. In this case, in order to keep the insertion amount constant, it is necessary to accurately grasp the position of the tip end and the position of the liquid level of the number of samples. However, prevention of mixing of sample liquid, Ul
iIn many cases, the above-mentioned chips are replaced each time for reasons such as manufacturing, and the dimensional accuracy of these chips is often not very high. For this reason, it is difficult to accurately grasp the position of the tip tip attached to the tip of the pipette, and it is difficult to control the insertion amount of the tip tip. Regarding,
For example, when there are bubbles on the liquid surface, there is a problem in that it is difficult to detect the liquid level position.

(Means for Solving the Problems) For these reasons, the present invention provides a
When the twisted nozzle member is moved up and down relative to the sample liquid, the lower end of the nozzle member (the lower end of the nozzle body or the lower end of the spotting tip attached to the nozzle body) comes into contact with the sample liquid. It is an object of the present invention to provide a liquid level detection device which is provided with a means for detecting the amount of the nozzle member and can thereby accurately determine the amount of insertion of the lower end of the nozzle member into the sample liquid.

As a means for this purpose, the apparatus of the present invention has a suction body arranged above a sample container containing a sample liquid so as to be movable up and down by vertical position control means, and a nozzle member provided at the lower end of the suction body. The sample liquid can be aspirated by the connected suction means, while the nozzle member is held with respect to the suction body by a vibrating vibration transmission plate, and a frequency is applied to the nozzle member by the vibration imparting means via the frequency control circuit. Vibration is applied while changing the frequency, and the extreme value of the output voltage or current value corresponding to the frequency change is detected from the output voltage or current value of the vibration applying means at this time, and the change in this extreme value is read and the vibration is applied to the nozzle member. The liquid surface position of the sample liquid is detected by detecting the contact between the sample liquid and the sample liquid. Note that there are no restrictions on the type of sample liquid or the shape of the nozzle member in this device, and various sample liquids and nozzle members can be used. In an automatic spotting device for the purpose of This is particularly effective for detecting the liquid level position and controlling the amount of insertion of the lower end of the nozzle member into the sample liquid. ~ (Function) According to the liquid level detection device of the present invention configured as above,
When the lower end of the nozzle member (nozzle body or spotting tip) comes into contact with the liquid surface, the vibration of the nozzle member applied by the vibration applying means receives resistance from the sample liquid, so that the output voltage or current of the vibration applying means decreases. Therefore, this change can be detected as a change in the extreme value of the output voltage or current with respect to the frequency of the applied vibration, and thereby the contact between the nozzle 81S material and the sample liquid can be detected reliably. In this way, even if bubbles are generated on the sample liquid surface, there is a large difference between the resistance due to the bubbles and the resistance due to the liquid, so contact with the liquid surface can be reliably detected. By moving the nozzle member downward by a predetermined amount from the position where contact between the member and the sample liquid is detected, it is easy to insert the lower end of the nozzle member into the sample liquid by a certain depth.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 is a perspective view showing an example of a chemical analysis apparatus having an automatic spotting device 50, and this automatic spotting device 50 is provided with a liquid level detection device according to the present invention. This chemical analysis device includes a main body 10, a cartridge 11, an incubator 20.
Lol! The feed/insertion means 40 and the automatic spotting device 50 are attached to the cover plate 16 that covers the main body 10.
The top view of FIG. 2 shows the top view with the holder removed. As shown in FIG. 1, this device includes a display section 14 that displays measurement data during measurement.
Although operation keys 15 for operating the display and the like and a magnetic disk insertion section 13 for recording are provided, these are omitted in FIG. 2.

The cartridge 11 stores several unused chemical analysis slides 1 in a stack, and the chemical analysis slides 1 are pushed out one by one backwards (in the direction of the arrow in FIG. 2) starting from the lowest one by the push lever 12. It is now possible to do so. An incubator 20 is located on the right side of this cartridge 11. Inside O are a plurality of storage chambers 2 for storing and holding chemical analysis slides 1 arranged on the same plane and to the right as the chemical analysis slide 1 at the lowest stage in the cartridge 11.
1.21..., 21 are formed. Is there a storage room in front of this incubator 20? A tray 29 is arranged to receive the used slides discharged from the tray 1. Further, a reading head (not shown) for measuring 91 degrees of reflective optics is disposed below the incubator 20 and is slidable laterally (in the direction of arrow C) so as to face the lower surface of the incubator 20 .

Note that this 1y rotation is performed by being driven by, for example, a near motor on a rail disposed horizontally below the incubator 20, and this rail is driven by a near motor or the like.
The read head extends to the lower surface of the cartridge 11 and can be slid to a position facing the lower surface of the cartridge 11, so that it can face the chemical analysis slide 1 at the lowest stage of the cartridge.

This allows the read head to
Not only can the reflective optical density of the slides 1 stored in each of the storage chambers 21 be measured, but also fog photometry can be performed to measure the reflective optical density of unused slides 1.

This incubator 10 has a built-in heater (not shown), and is capable of maintaining (incubating) the chemical analysis slides 1 held in the storage units 21, 21, . . . 121 at a constant temperature. Chemical analysis slide 1
A dry multilayer film consisting of a support, a reagent layer, and a developing layer are placed in this order in a frame with a circular hole for dropping a liquid sample, and a sample such as urine or blood is placed on this film. A fixed amount is dropped, and this is kept at a constant temperature in the incubator 10 to cause a color reaction.

On the other hand, at the rear of the incubator 20, a transport/insertion means 40 that faces the entrance opening 21a of the storage chamber 21 and is slidable laterally (in the direction of arrow C) is arranged. This sliding movement is caused by the transport/insertion section F24 placed on a rail 49 extending laterally.
0 is driven by, for example, a linear motor, etc., and is used not only for the incubator 20 but also for the cartridge 1.
1 (the position indicated by the chain line X in FIG. 2).

Therefore, the chemical analysis slide 1 pushed out from the cartridge 11 by the pushing lever 12 is picked up by the transport/insertion means 40 slid to the position indicated by the chain line X, and transported to a predetermined position. 1 into a predetermined storage chamber 21.

An automatic spotting device 50 equipped with a rotatable spotting arm 30 is disposed behind the conveyance/insertion means 40, as shown by arrow B in FIG. This spotting arm 30 also acts as a suction body, and has a spotting tip 35 at its tip.
is removable, and its tip rotates in the direction of arrow B to move to the suction position located above the sample container 52 placed on the main body 10 (the position indicated by the chain line in the figure) and the main body 10. It is movable between a spotting position located above the spotting hole 19 formed in the upper cover plate 16 (the position indicated by the solid line in the figure). Below the spotting hole 19, there is a predetermined position indicated by a solid line Y in FIG. In the spotting position, the tip of the spotting tip 35 is located above the reagent layer of the slide 1 at the spotting position. Therefore, at the suction position, a predetermined amount of the sample liquid in the sample container 52 is sucked into the spotting tip 35, and then the spotting arm 30 is rotated in the direction of arrow B to spot the spotting tip 35. After that, the sample liquid can be dripped onto the reagent layer of the slide 1. After this, this slide 1
is inserted into an empty storage space 21 of the incubator 20 for incubation, and the optical reflection density at this time is read by a reading head to perform chemical analysis of the sample liquid. Note that a reference white plate 17 is provided between the incubator 20 and the cartridge 11 for correcting photometric errors caused by the reading head.

The operation of the chemical analysis apparatus configured as described above will be explained in detail.

First, the reading head moves to a position facing the bottom surface of the cartridge 11, and fog photometry is performed on the lowest chemical analysis slide 1 among the chemical analysis slides 1 stacked in the cartridge 11. Note that when the reading head is moved, it faces the reference black and white density plate 17 to correct photometric errors. After this fog photometry is carried out, the chemical analysis slide 1 is pushed out by the pushing lever 12 onto the conveying/inserting means 40, which has been moved to the position indicated by the two-dot chain line X in FIG. 2, and is held there. The conveyance/insertion means 40 moves to the right on the rail 49 to a position below the spotting position (the position indicated by the solid line Y). Next, automatic spotting device 5
0, the sample in the sample container 52 is sucked into the spotting tip 35 at the suction position (details of the suction operation into the spotting tip and the structure of the spotting arm 30 will be described later), and at the spotting position. The reagent is dripped onto the reagent layer of the slide 1 that has been transported to the position indicated by Y above. After this,
The conveyance/insertion means 40 moves laterally (in the direction of arrow C) on the rails 49 to place the incubator 20 in a predetermined storage position.
The slide 1 is inserted into this housing 21 facing the slide 1 .

The slide 1, which is kept at a constant temperature (incubation) in the incubator 20, is irradiated with irradiation light and its reflected optical density is measured by a reading head that has been moved below the storage chamber, thereby performing chemical analysis of the sample. When these measurements are completed, the chemical analysis slide 1 is discharged from the storage tray 21 into the tray 29 by the transport/insertion means 40. Thereafter, by repeating the above operations, it is possible to automatically and continuously perform chemical analysis using a large number of chemical analysis slides.

When performing the above measurement, an automatic spotting system is used to aspirate the sample liquid in the sample container 52 into the spotting tip 35, and then automatically dispense the sample liquid from the spotting tip 35 onto the reagent layer of the slide 1. The apparatus 50 will be described in detail below.

The configuration of this automatic spotting device 50 is shown in FIG. 3. This device 50 includes a spotting arm 30 with a spotting tip 35 removably attached to the lower end, and a tip that moves the spotting arm 30 up and down. Position control means 60, tip moving means 70 for rotating the spotting arm 30 and moving the spotting tip 35 between the suction position and the spotting position. and a suction/discharge means 80 that communicates with the chip 35 and sucks the sample liquid into the chip 35 and discharges the sample liquid from within the chip 35.

The spotting arm 30 includes an arm body 31 that is rotatable about a rotation axis 31b with respect to the main body 10, and a vibration transmission plate 32 that can vibrate and is cantilevered by the arm body 31 at the end opposite to the rotation WA31b. , a nozzle body 33 held by the vibration transmission plate 32, a rotor 34 made of piezoelectric ceramic or the like attached to the vibration transmission plate 32, and a spotting tip detachably attached to the lower end of the nozzle body 33. It consists of 35. The nozzle body 33 has a through hole extending vertically, the lower end of which communicates with the inner space 35a of the dotting tip 35, and the upper end communicating with the passage 31 formed in the arm body 31 via a hose 36.
Connects to a. The first moving element 34 itself vibrates in response to an electric signal applied from the outside, which causes the vibration transmission plate 32 to vibrate, and the nozzle body 3 held thereto to vibrate.
3 and the point observation chip 35 are also subjected to vibrations of the same frequency.

The electrical signal to this vibrator 34 is sent from the controller 90, and the function of this controller 90 is controlled by the fifth controller.
This will be explained using the block diagram shown in the figure. The electric image @ to the vibrator 34 is determined by a signal outputted from the sweep generator 91 via the voltage control oscillator 92, so that the vibrator 34 operates within a predetermined frequency range (for example, 0 to 1KH2). It vibrates while changing the frequency in a sweeping motion. In other words, the sweep generator 91 generates voltage control! The radiator 92 and the vibrator 34 constitute a frequency control circuit as shown in the figure. The vibration of the vibrator 34 is transmitted to the nozzle body 33 and the spotting tip 35 via the vibration transmission plate 32, and these also vibrate. Note that since the hose 36 is flexible, the hose 36 is connected to the arm body 31.
There is almost no vibration transmission to. In this way, the vibrator 3
4 power < 4Ji, the voltage (V) across the fixed resistor 93 arranged in series with the vibrator 34 in the frequency control circuit or the current (1) flowing through this resistor is measured, and this is measured by the amplifier 94. is amplified by the extreme value detection means 95
sent to. This extreme value detection means 95 detects the voltage (V) or current (1) that becomes the output voltage or current of the vibrator 34 in accordance with the swept frequency, and the relationship between the two is shown in FIG. 6, for example. (The figure shows the relationship between voltage (V) and frequency, but since voltage and current have a proportional relationship, current may be used instead of voltage.) That is, from the relationship with the natural frequencies of the vibration transmission plate 32, the nozzle body 33, and the spotting tip 35, a relationship is obtained in which the voltage (V) has a local maximum value Q and a local minimum value P for a certain frequency.

When the lower end of the spotting tip 35 is away from the sample liquid surface of the sample container 52, the positions of these extreme values P and Q remain constant regardless of the vertical movement of the spotting arm 30; 35
When the lower end of the contact points contact the surface of the sample liquid, the resistance of the sample liquid changes and the voltage (V) value changes with respect to the frequency, as shown by the broken line in Figure 6, for example. P,
Q moves to the position of P' and Q'. Therefore, the extreme value detection means 95 stores the extreme values P and Q when the lower end of the spotting tip 35 is away from the liquid surface, and the spotting arm 30 is moved downward by the tip vertical position control means 60. The detected extreme value and the stored extreme value are compared in the comparison circuit 96, and the difference between the lower end of the dotting tip 35 and the liquid level is determined based on the presence or absence of a change in this extreme value. It is designed to detect the presence or absence of contact with the liquid and detect the liquid level position.

In response to the detection of the presence or absence of contact with the liquid surface, an operation control signal is sent from the motor operation control circuits 97 and 98 to the pulse motor 61 of the vertical position control means 60 and the piston drive motor 81 of the suction/discharge means 80, and the The vertical movement a of the landing arm 30 and the suction and discharge of the sample liquid to the spotting tip 35 are controlled.

The chip vertical position control means 60 is connected to a pulse motor 61 attached to the main body 10 and a rotating shaft of the pulse motor 61 via a coupling 62. ! ! It consists of a squared drive body 63 and a driven body 64 having a male thread 64b that engages with a female thread 638 formed on the drive body 63. Subject 6
4 is a recess 6 that loosely fits into the protrusion 10a of the main body 10, as shown in FIG.
4a, and is movable up and down relative to the main body 10, but rotation is prevented. Roughly speaking, the rotating shaft 31b of the spotting arm 30 is connected to the upper part of the driven body 64 so as to be able to rotate relative to each other. Therefore, when the driving body 63 is rotated by the pulse motor 61, the driven body 64 is prevented from rotating, so the screw engagement opening with the driving body changes, the driven body 64 is moved up and down, and at this time, the driven body 64 is prevented from rotating. The rotation t@31b of the spotting arm 30 connected to the body 64 is also moved up and down.

The chip moving means 70 includes a rotary motor 71 attached to the main body 10, a drive gear 73 connected to the rotating shaft of the rotary motor 71 via a coupling 72, and meshes with the drive gear 73 and is driven. It consists of a driven gear 74 that is movable up and down with respect to the gear 73, and the driven gear 74 is coaxially fixed to the rotating shaft 31b of the spotting arm 30. The rotation shaft 31b of the spotting arm 30 is rotatably supported by the main body 10. Therefore, when the rotation motor 71 is driven to rotate, this rotation is transmitted through the coupling 72, the drive gear 73, and the driven gear 74. The rotation 111131b is transmitted. As a result, the spotting arm 30 is rotated around the rotating shaft 31b, and the spotting tip 35 attached to the tip of the spotting arm 30 can be moved between the suction position and the spotting position. There is.

The suction/discharge means 80 includes a piston drive motor 81 having a cam plate 82 on the rotating shaft, and a link 8 between the cam plate 82 and the piston drive motor 81 .
3, and a piston 84a attached to the tip of this piston rod 84.
A flexible cylinder 85 in which the cylinder 85 is fitted, and a passage 31a formed in the spotting arm 30 and communicating with the space 35a in the spotting tip 35 via the hose 36 and the nozzle body 33, communicate with the space 86 in the cylinder 85. hose 87
It consists of. The rotational movement of the piston drive motor 81 is converted into a reciprocating movement of the piston rod 84 by the link 83, and the resulting reciprocating movement of the piston 85 changes the volume of the cylinder interior space 86, which causes the flexible hose 87 and the spotting arm 30 to change. The liquid is transmitted to the spotting tip internal space 35a through the passage 31a etc. in the spotting tip, and the sample )]'i is inhaled or discharged into the spotting tip internal space 35a.

Regarding the operation of the automatic spotting device configured as above (
I will clarify. First, the sample container 52 containing the sample liquid is placed, and the vibrator 34 is activated by a signal from the frequency control circuit of the controller 90. Next, the chip vertical position control hand 1
60, the spotting arm 30 is in the suction position and the spotting tip 3 attached to the tip of this arm 30 is activated.
When the C spotting tip 35 is moved down a predetermined distance and comes into contact with the lower end of the spotting tip 35 or the surface of the sample liquid in the sample container 52, as shown in FIG. The extreme values P and Q of the output voltage (V) change to P' and Q'.

Therefore, by detecting this change, the spotting tip 3
The contact between the spotting tip 35 and the sample liquid can be reliably detected. Depending on the insertion depth of the lower end of the spotting tip 35 into the liquid, the extreme values P', Q Since the amount of change in ' is different, it is also possible to detect the insertion depth based on the amount of change. In this way, even when it is difficult to see the liquid level position due to bubbles on the liquid surface, the dotting tip 35 can be easily adjusted. Contact between the lower end and the sample liquid can be detected reliably.

Next, the spotting tip 35 is moved down by a predetermined distance of 1 h from the position where it came into contact with the surface of the sample liquid in this way, and the lower end of the spotting tip 35 is inserted into the sample liquid by a predetermined depth h. Note that this predetermined depth h is desirably as shallow as possible in order to reduce the amount of sample liquid adhering to the outer periphery of the lower end of the spotting tip 35. Thereafter, the suction/discharge means 80 is actuated to move the piston 84a, and a predetermined amount of the sample liquid is sucked into the space 35a of the spotting tip 35.

When a specified amount of sample liquid is sucked into the space 35a in the spotting tip 35 as described above, the tip vertical position control means 60
The spotting arm 30 is moved upward and the spotting tip 35 is lifted. Thereafter, the spotting arm 30 is rotated about the rotating shaft 31b by the tip moving means 70, and the spotting tip 35 is moved from the suction position to the spotting position. Next, the spotting tip 35 is moved down by the tip vertical position control means 60, and when its tip is located near the upper part of the reagent layer of the slide 1, the sample liquid in the spotting tip 35 is removed by the action of the suction/discharge means 80. is slowly discharged, and a liquid is formed at the lower end of the spotting tip 35. Then, the spotting tip 35 continues to descend and the liquid is spotted and supplied onto the reagent layer portion of the slide 1. If the spotting tip 35 is moved upward, the spotting of the sample liquid is completed.

In the above, the automatic spotting device that automatically spots and supplies a sample liquid onto the reagent layer of a chemical analysis slide detects the contact between the spotting tip 35 and the sample liquid and determines the liquid surface position of the sample liquid. Although the liquid level detecting device for detection has been described, the liquid level detecting device of the present invention is not limited to the above example, and it goes without saying that it can be used to detect the liquid level position of various liquids.

Further, in the above embodiment, the vibrator 3 is attached to the vibration transmission plate 32.
4 is attached, but as shown in FIG. 7, the vibrator 34 is attached on the nozzle body 33',
Alternatively, the vibration may be applied directly to the nozzle body 33' held by the nozzle body 33'. Roughly speaking, as shown in FIG. 8, a piezoelectric actuator 3 that integrates a vibration transmission plate and a vibrator
8 to support the nozzle body 33'' and vibrate the piezoelectric actuator 38 itself.

(Effects of the Invention) As explained above, according to the present invention, the nozzle member held on the suction body via the disturbance transmission plate is swept with vibrations of a predetermined frequency by the vibration imparting means (vibrator). The device detects the extreme value of the output voltage (current) of the vibration applying means that corresponds to the applied and swept frequency, so if a change in this extreme value is detected, the lower end of the nozzle means will be connected to the sample liquid. It is possible to detect whether or not the liquid has come into contact with the liquid, and the liquid level can be reliably detected. In particular, in this case, there is no need to detect the initial position of the lower end of the nozzle means or the initial position of the liquid level, so there are no restrictions on the size or shape of the sample container or the amount of liquid to be put into this container. When a spotting tip is used as a means, there is an advantage that there are no restrictions on the shape and size of this spotting tip.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a chemical analyzer having a liquid level detection device according to the present invention, Fig. 2 is a plan view showing the above chemical analyzer with the cover plate removed, and Fig. 3 is a configuration of the above chemical analyzer. Automatic spotting device 1
A schematic cross-sectional view showing an example; FIG. 4 is a cross-sectional view along arrow IV-IV in FIG. 3; FIG. 5 is a block diagram showing the operation of the controller used in the liquid level detection device of the present invention; Graphs showing the relationship between frequency and voltage detected in the liquid level detecting device of the present invention, and FIGS. 7 and 8 are cross-sectional views showing other embodiments of the liquid level detecting device according to the present invention. 10... Main body 11... Car 1 to Azalea 16... Cover plate 20... Incubator 30... Spotting arm 32... Vibration transmission plate 33... Nozzle body 34... Vibrator 35
... Spotting tip 40 ... Conveyance/insertion means 5
0... Automatic point @ device 60... Chip upper and lower neck control means Fig. 1 Fig. 3 @ Fig. 4 March 9, 1988 1. Case description 1985 Patent Application No. 246.146
No. 2. Name of the invention Liquid level detection device 3. Relationship with the person making the amendment Case Name of the patent applicant Address 210 Nakanuma, Minamiashigara City, Kanagawa Prefecture Name (
520) Fuji Photo Film Co., Ltd. Representative Minoru Onishi 4, Agent address: 6, 7th floor, Hauraiya Building, 5-2-1 Roppongi, Minato-ku, Tokyo, "Detailed description of the invention" column of the specification subject to amendment 7. Contents of amendment 1) Correct “Reference white board J” on page 15, lines 18-19 of the specification to “Reference monochrome density plate” 2) Change “chain line X” on page 14, lines 3 and 5 to “ ``Double-dashed line X'' is corrected.

Claims (1)

[Claims] 1) a sample container containing a sample liquid; a suction body located above the sample container and having a suction nozzle member at the lower end;
Vertical position control means for vertically moving the suction body communicates with the nozzle member, and the suction body is moved downward by the vertical position control means so that the nozzle member at the lower end of the suction body is in the sample liquid. a suction means for aspirating the sample liquid through the nozzle member when the sample liquid is inserted into the sample liquid suction device; vibration applying means for applying vibrations at a predetermined frequency to the nozzle member held by the vibration transmission plate;
a frequency control circuit that changes the frequency of vibration applied to the nozzle member by the vibration applying means; and a frequency control circuit that detects the output voltage or current value of the vibration applying means, and detects the output voltage or current value corresponding to the change in the frequency. an extreme value detection means for detecting an extreme value, and detects contact between the nozzle member and the sample liquid based on a change in the extreme value detected by the extreme value detection means, and detects the liquid level position of the sample liquid. A liquid level detection device characterized in that: 2) The sample liquid is a sample liquid containing a substance to be measured that is spot-supplied onto a reagent layer of a chemical analysis slide, and the suction nozzle member is connected to a nozzle body connected to the suction means and the nozzle body. It consists of a dotting tip attached to the tip,
2. The liquid level detection device according to claim 1, wherein contact between the lower end of the spotting tip and the sample liquid is detected based on a change in the extreme value. 3) The vibration applying means is attached to the vibration transmission plate, and applies vibration to the nozzle member via the vibration transmission plate. The liquid level detection device according to item 2. 4) The liquid level detection device according to claim 1 or 2, wherein the vibration imparting means is attached to the nozzle member. 5) The liquid level detection device according to claim 1 or 2, wherein the vibration imparting means and the vibration transmission plate are integrally constructed.