JPH06249862A - Detection of anomaly of dispensing device and device therefor - Google Patents

Abstract

PURPOSE:To suppress the generation of the bridge phenomenon of the dispensing objective liquid inside a dispensing nozzle and the adhesion of dirt due to proteins by detecting the resisdnace between electrodes installed in the axial direction of the dispensing nozzle when liquid is poured. CONSTITUTION:A dispensing nozzle 1 made of the electric conductive material such as stainless steel is half divided in the axial direction, and an insulative member 1c is interposed between the divided parts 1a and 1b, and used as a pair of electrodes. The position df the insulative member 1c is set so that both the divided parts 1a and 1b contact a dispensing objective liquid in the state where a prescribed quantity of dispensing objective liquid is poured. At the time point when the prescribed pouring operation is carried out in order to pour a prescribed quantity of dispensing objective liquid, the electric resistance between both the divided parts 1a and 1b is measured. An anomaly indication signal output part 10 judges if the dispensing objective liquid is actually poured or not, i.e., clogging is generated in the dispensing nozzle 1 or not by judging if the resistance value between both the divided parts 1 and 1b is larger than a prescribed threshold value or not.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting abnormality in a dispensing device, and more specifically, a dispensing device for accurately setting the amount of liquid to be dispensed in various inspections. In the above, the present invention relates to a method for detecting the occurrence of an abnormal state that hinders the accurate setting of the amount of liquid to be dispensed.

[0002]

2. Description of the Related Art Conventionally, there has been proposed a device for detecting clogging of a dispensing nozzle among abnormal states which may occur in the dispensing device (Actual Kaihei 2-135865).
(See Japanese Patent Publication). The above device is equipped with a sensor for discriminating between gas and liquid on the inner surface at a predetermined position near the tip of the dispensing nozzle, and when the dispensing nozzle system is operated to suck a predetermined amount of liquid. First, it is determined whether gas or liquid is present at the position corresponding to the sensor. Specifically, if the dispensing nozzle is clogged,
Even if the above operation is performed, the liquid is not sucked, and the sensor determines that gas is present. On the contrary, if the dispensing nozzle is not clogged, the liquid is sucked in with the above operation,
The sensor determines that liquid is present. Therefore, it is sufficient to determine that the dispensing nozzle is clogged only when the sensor determines that gas is present while the dispensing nozzle system is operating.

[0003]

Since the above dispensing nozzle is used to accurately set a minute injection amount of liquid (usually about several μl to several hundred μl), the inner diameter of the dispensing nozzle is Inevitably, the diameter must be remarkably small (when dealing with the above-mentioned dispensing amount, the inner diameter must be set to about 1 mm). Therefore, providing a sensor made of an electrode or the like on the inner surface of a dispensing nozzle having such a small diameter as disclosed in the above publication requires, for example, that an insulator be interposed between the dispensing nozzle and the sensor. It is extremely difficult due to the restriction of. Further, even when the sensor can be provided on the inner surface of the dispensing nozzle by overcoming this difficulty, since the inner diameter of only the portion corresponding to the sensor is significantly reduced, the bridge phenomenon of the liquid to be dispensed may occur. In addition to easy occurrence, a step is generated due to the provision of the sensor, and since the material of the dispensing nozzle and the material of the sensor are generally completely different, stains caused by proteins contained in the liquid to be dispensed However, there are inconveniences such as easy adhesion.

That is, if the bridge phenomenon of the liquid to be dispensed occurs, the presence of the liquid is detected by the sensor, and the clogging of the dispensing nozzle cannot be detected.
Further, if stains caused by proteins or the like are attached, it is necessary to sufficiently clean the dispensing nozzle system, so that the time required for the dispensing process for measurement or the like is shortened by the time required for cleaning. . In particular, when an inspection or the like is performed, generally, a plurality of types of liquids must be sequentially dispensed, so that the time required for the inspection or the like becomes long as a whole as the above time is shortened.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is possible to enhance the workability for mounting a sensor and to generate a bridge phenomenon of a liquid to be dispensed inside a dispensing nozzle. It is an object of the present invention to provide a method for detecting an abnormality in a dispensing device which can significantly reduce the adhesion of stains caused by proteins and the like and can reliably detect an abnormality in the dispensing nozzle system.

[0006]

According to a first aspect of the present invention, there is provided a method for detecting an abnormality in a dispensing apparatus, wherein a predetermined position of a dispensing nozzle corresponding to a dispensing amount is an electrode gap. A pair of electrodes is provided in the axial direction of the dispensing nozzle to output an abnormality indicating signal indicating that normal liquid suction is not possible in response to a large interelectrode resistance during liquid suction for dispensing. Is the way.

According to a second aspect of the method for detecting an abnormality in a dispensing apparatus, a sensor for detecting the liquid level of a liquid to be dispensed is provided at a predetermined position and responds to an output signal from the sensor when inhaling the liquid for dispensing. Then, an abnormality instruction signal indicating whether or not the normal liquid suction is not performed is output. The abnormality detecting method in the dispensing apparatus according to claim 3, wherein a sensor for detecting the liquid level of the liquid to be dispensed is provided at a predetermined position corresponding to a liquid amount larger than the maximum dispensing amount of the dispensing nozzle system. Is.

According to a fourth aspect of the present invention, there is provided an abnormality detecting method for a dispensing device, wherein a sensor for discriminating between a gas and a liquid is provided at a predetermined position of a dispensing nozzle system, and a suction operation and a discharge are performed so as to interpose an air layer for liquid separation. In this method, an operation is performed, and in response to the detection of two or more air layers by the sensor during these operations, an abnormality instruction signal indicating the dirt inside the dispensing nozzle system is output.

According to a fifth aspect of the present invention, there is provided a method of detecting an abnormality in a dispensing apparatus, wherein a sensor for discriminating between a gas and a liquid is provided at a predetermined position of a dispensing nozzle system to prevent an air layer for liquid separation from intervening. This is a method of performing a suction operation and / or a discharge operation, and outputting an abnormality instruction signal indicating liquid leakage of the dispensing nozzle system in response to the air layer being detected by the sensor during these operations.

In the abnormality detecting device in the dispensing device according to the sixth aspect, a pair of electrodes is provided in the axial direction of the dispensing nozzle so that a predetermined position corresponding to the dispensing amount of the dispensing nozzle is an electrode gap. At the same time, a pair of electrodes is formed so that the inner surface of the electrode is flush with the inner surface of the dispensing nozzle, and normal liquid is produced in response to the large interelectrode resistance during liquid intake for dispensing. An abnormality signal output means for outputting an abnormality instruction signal indicating that the inhalation is not possible is provided.

[0011]

According to the method of detecting an abnormality in the dispensing device according to claim 1, a pair of electrodes having a predetermined position corresponding to the dispensing amount of the dispensing nozzle as an electrode gap is provided in the axial direction of the dispensing nozzle. Therefore, when the dispensing nozzle is made of a conductive material, the dispensing nozzle is divided at a predetermined position, an insulating member is interposed in the divided portion, and conversely, the dispensing nozzle is made of an insulating material. In the case of (1), the dispensing nozzle is divided into three parts, and the conductive member is interposed in each of the divided parts, whereby the electrode can be attached to the dispensing nozzle. Therefore, the workability can be significantly improved as compared with the conventional example in which the sensor is mounted on the inner surface of the dispensing nozzle. Further, since an abnormality indicating signal indicating that normal liquid suction is not performed is output in response to a large interelectrode resistance during liquid suction for dispensing, there has been a problem in the conventional example. It is possible to prevent the influence of the bridging phenomenon and achieve accurate abnormality detection. Further, since the inner surfaces of the electrically conductive portion and the electrically insulating portion can be made flush with each other, the adhesion of dirt caused by proteins and the like can be significantly reduced, and the cleaning of the dispensing nozzle can be minimized. As a result, the time required for inspection and the like can be shortened as compared with the conventional example.

According to the abnormality detecting method in the dispensing apparatus of the second aspect, since the sensor for detecting the liquid surface of the liquid to be dispensed is provided at the predetermined position, the sensor is provided at the predetermined position on the outer surface of the dispensing nozzle, and the dispensing is performed. It only needs to be provided in the target solution storage portion or the like, and the workability can be significantly improved as compared with the conventional example in which the sensor is provided on the inner surface of the dispensing nozzle. In addition, since it outputs an abnormality instruction signal indicating whether or not normal liquid suction is not possible in response to the output signal from the sensor during liquid suction for dispensing, it is a problem in the conventional example. It is possible to prevent the influence of the conventional bridging phenomenon and to achieve accurate abnormality detection. Furthermore, since the inner surface of the dispensing nozzle can be kept flush, it is possible to significantly reduce the adhesion of dirt caused by proteins and the like, and to clean the dispensing nozzle to the minimum necessary. As a result, the time required for inspection and the like can be shortened as compared with the conventional example.

According to the abnormality detecting method in the dispenser of the third aspect, the sensor for detecting the liquid level of the liquid to be dispensed is provided at a predetermined position corresponding to a liquid amount larger than the maximum dispensing amount of the dispensing nozzle system. Therefore, if the liquid level is not detected by the sensor in this state, the dispensing nozzle system is operated to suck the liquid, and then the dispensing nozzle system is operated to suck the gas. It is possible to detect that the nozzle is clogged. Also, even if the amount of liquid inhaled changes,
Since the liquid level detection position can be kept constant by complementarily changing the gas suction amount, it is possible to easily deal with various dispensing amounts and to reliably detect clogging of the dispensing nozzle.

According to the abnormality detecting method in the dispensing device of the fourth aspect, a sensor for discriminating between gas and liquid is provided at a predetermined position of the dispensing nozzle system, and a suction operation is performed so as to interpose an air layer for liquid separation. And the discharge operation is performed, and in response to the detection of two or more air layers by the sensor during these operations, the abnormality instruction signal indicating the dirt inside the dispensing nozzle system is output. It is not necessary to provide a sensor for directly detecting the dirt inside the system, and it is only necessary to detect whether or not two or more air layers are detected while performing the suction operation and the discharge operation by simply interposing an air layer for liquid separation. Based on that, the detection of dirt can be achieved.

According to the abnormality detecting method in the dispensing device of the fifth aspect, a sensor for discriminating between gas and liquid is provided at a predetermined position of the dispensing nozzle system to prevent the air layer for liquid separation from intervening. In order to perform the suction operation and / or the discharge operation in order to do so, in response to the detection of the air layer by the sensor during these operations, the abnormality instruction signal indicating the liquid leakage of the dispensing nozzle system is output. If the air layer is detected while performing the suction operation and / or the discharge operation without interposing the air layer in order to clean the dispensing nozzle system, it can be determined that liquid leakage has occurred. . Therefore, it is not necessary to separately provide a liquid leakage sensor at a location where liquid leakage may occur, and the configuration can be greatly simplified.

In the abnormality detecting device in the dispensing device according to the sixth aspect, a pair of electrodes are provided in the axial direction of the dispensing nozzle so that a predetermined position of the dispensing nozzle corresponding to the dispensing amount is set as an electrode gap. In addition, a pair of electrodes is formed so that the inner surface of the electrode is flush with the inner surface of the dispensing nozzle. Since the abnormal signal output means for outputting the abnormal instruction signal indicating that the liquid has not been sucked in is provided,
When the dispensing nozzle is made of a conductive material, the dispensing nozzle is divided at a predetermined position, an insulating member is interposed in the divided portion, and conversely, the dispensing nozzle is made of an insulating material. In this case, the dispensing nozzle is divided into three parts, and the conductive member is interposed in each divided part, whereby the electrode can be attached to the dispensing nozzle. Therefore, the workability can be significantly improved as compared with the conventional example in which the sensor is mounted on the inner surface of the dispensing nozzle. Also,
Since the abnormal indicator signal indicating that normal liquid suction is not performed is output in response to the large interelectrode resistance during liquid suction for dispensing, the bridging phenomenon which has been a problem in the conventional example. It is possible to prevent the influence of and to accurately detect the abnormality. Further, since the inner surfaces of the electrically conductive portion and the electrically insulating portion can be made flush with each other, the adhesion of dirt caused by proteins and the like can be significantly reduced, and the cleaning of the dispensing nozzle can be minimized. As a result, the time required for inspection and the like can be shortened as compared with the conventional example.

[0017]

Embodiments will be described in detail below with reference to the accompanying drawings showing embodiments. FIG. 2 is a central vertical cross-sectional view showing an example of the configuration of a dispensing nozzle in which the abnormality detecting method in the dispensing device of the present invention is carried out. The dispensing nozzle 1 made of a conductive material such as stainless steel is arranged in the axial direction 2 In addition to the division, the insulating member 1c is interposed between the divided portions 1a and 1b of the dispensing nozzle 1. The divided portions 1a and 1b are used as a pair of electrodes. Further, it is determined whether or not the electric resistance between the pair of divided portions 1a and 1b is larger than a predetermined threshold value, and in response to the electric resistance being larger than the predetermined threshold value, the dispensing nozzle 1 is clogged. It has an abnormality instruction signal output unit 10 that outputs a signal indicating that it is occurring. The insulating member 1
The intervening position of c is set to a predetermined position that is determined based on the inner diameter of the dispensing nozzle 1 and the dispensing amount, and the electrode interval defined by the insulating member 1c is the thickness of the air layer to be formed for liquid separation. It is defined in accordance with. of course,
The inner surface of each of the divided portions 1a and 1b and the inner surface of the insulating member 1c are formed flush with each other. The insulating member 1c preferably has water repellency, and examples thereof include a fluorine-based resin and a synthetic resin having a surface coated with fluorine.

FIG. 1 is a flow chart for explaining an embodiment of a method for detecting an abnormality in the dispensing apparatus of the present invention. In step SP1, a first suction operation is performed to form an air layer, and in step SP2 a predetermined amount is reached. The second suction operation is performed to suck the liquid in step SP3.
At, the electric resistance value between the electrodes 1a and 1b is measured, and at step SP4, it is determined whether or not the electric resistance value is larger than a predetermined threshold value. When it is determined that the electric resistance value is larger than the predetermined threshold value, step SP5
Indicates that the dispensing nozzle 1 is clogged. After the processing of step SP5 is performed, or when it is determined in step SP4 that the electric resistance value is equal to or lower than the predetermined threshold value, the series of processing is ended as it is.

A more detailed description will be given. When dispensing an accurate amount of liquid using a dispensing nozzle system including the dispensing nozzle 1, it is preferable to fill the dispensing nozzle system with an incompressible liquid, for example, water. Since it is necessary to prevent the concentration change due to the liquid to be dispensed being mixed with water, first, a small amount of air is inhaled to prevent the mixture of water and the liquid to be dispensed. . Then, a predetermined amount of the liquid to be dispensed is inhaled. Then, the liquid to be dispensed and the air can be discharged to achieve accurate dispensing of the liquid to be dispensed. Therefore, if the position of the insulating member 1c is set so that the divided portions 1a and 1b come into contact with the liquid to be dispensed when a predetermined amount of the liquid to be dispensed is inhaled, The liquid to be dispensed is measured by measuring the electric resistance value between the divided portions 1a and 1b at the time when a predetermined suction operation is performed to suck the liquid and determining whether or not it is larger than a predetermined threshold value. It is possible to determine whether or not is actually inhaled, that is, whether or not the dispensing nozzle 1 is clogged.

When the dispensing nozzle 1 is clogged, the intended inspection cannot be achieved. Therefore, the dispensing nozzle 1 is displayed with a message indicating that the nozzle is clogged. Ends the process. On the contrary, when the dispensing nozzle 1 is not clogged, the necessary processing is performed as it is to perform the desired inspection. As is clear from the above description, in this embodiment, the electrode is not provided on the inner surface of the dispensing nozzle 1, but the dispensing nozzle 1 made of a conductive material is divided into two parts, and both divided parts 1a are formed. , 1b
Since the insulating member 1c is interposed between the two, the workability can be significantly improved. Further, since the inner surface of the dispensing nozzle 1 can be made flush over the entire range, it is possible to prevent the occurrence of the bridging phenomenon and the attachment of stains due to proteins and the like.

FIG. 3 is a vertical cross-sectional view showing another example of the structure of the dispensing nozzle. The dispensing nozzle 2 made of an insulating material such as synthetic resin is axially divided into three parts, and the divided parts 2a,
2b and between the divided portions 2b and 2c.
d and 2e are interposed. Then, the conductive member 2d,
2e is a pair of electrodes. Further, it is determined whether the electric resistance between the pair of conductive members 2d and 2e is larger than a predetermined threshold value, and the dispensing nozzle 2 is clogged in response to the electric resistance being larger than the predetermined threshold value. The abnormality instruction signal output unit 10 that outputs a signal indicating that the occurrence of is generated. The intervening positions of the conductive members 2d and 2e are set to predetermined positions determined based on the inner diameter of the dispensing nozzle 1 and the dispensing amount, and the electrode interval defined by the dividing portion 2b is formed for liquid separation. It is defined according to the thickness of the air layer to be formed. Of course, the inner surfaces of the divided portions 2a, 2b, 2c and the inner surfaces of the conductive members 2d, 2e are formed flush with each other. In addition, as the above-mentioned division parts 2a, 2b, 2c,
It preferably has water repellency, and examples thereof include a fluorine-based resin and a synthetic resin having a fluorine-coated surface.

Therefore, also in this case, it is possible to surely determine whether or not the dispensing nozzle 2 is clogged by performing the processing of the flowchart of FIG.

[0023]

[Embodiment 2] FIG. 5 is a central vertical cross-sectional view showing an example of the configuration of a dispensing nozzle and a liquid storage portion for dispensing to which the abnormality detecting method in the dispensing device of the present invention is applied. A pair of electrodes 3a and 3b are provided on the outer surface at predetermined positions on a plane perpendicular to the central axis. In this case, the dispensing nozzle 3 may be made of a conductive material or an insulating material. However, when the dispensing nozzle 3 is made of a conductive material, the electrodes 3a and 3b are interposed with an insulating layer (not shown) interposed.
Will be provided. In addition, 3c is a liquid storage part for dispensing.

FIG. 4 is a flow chart for explaining another embodiment of the abnormality detecting method in the dispensing device of the present invention.
In step SP1, the dispensing nozzle 3 is moved so that the pair of electrodes 3a and 3b both come into contact with the liquid to be dispensed,
In step SP2, the electric resistance value between the pair of electrodes 3a and 3b is measured, and in step SP3, it is determined whether or not the electric resistance value is less than or equal to a predetermined threshold value. Step SP
When it is determined in 3 that the electric resistance value is larger than the predetermined threshold value, the processing of step SP1 is repeated again.

When it is determined in step SP3 that the electric resistance value is less than or equal to the predetermined threshold value, the suction operation is performed to suck a predetermined amount of liquid in step SP4, and both electrodes 3a, 3b are operated in step SP5. The electric resistance value between them is measured, and it is determined in step SP6 whether or not the electric resistance value is larger than a predetermined threshold value. When it is determined that the electric resistance value is equal to or less than the predetermined threshold value, it is displayed in step SP7 that the dispensing nozzle 1 is clogged. After the processing of step SP7 is performed, or when it is determined in step SP6 that the electric resistance value is larger than the predetermined threshold value, the series of processing is ended as it is.

In other words, if the dispensing nozzle 3 is not clogged, the liquid suction operation is performed to lower the liquid level of the dispensing target liquid in the dispensing target liquid storage portion 3c, so that the electricity between the electrodes 3a and 3b is reduced. The resistance value becomes larger than a predetermined threshold value. On the contrary, if the dispensing nozzle 3 is clogged, even if an operation for sucking the liquid is performed, the dispensing target liquid container 3
Since the liquid level of the liquid to be dispensed in c does not change, the electric resistance value between the electrodes 3a and 3b is maintained at a predetermined threshold value or less.

Therefore, only by comparing the magnitude of the electric resistance value between the electrodes 3a and 3b with a predetermined threshold value, it is possible to reliably determine whether or not the dispensing nozzle 3 is clogged. Of course, the electrode 3 is not on the inside of the dispensing nozzle 3 but on the outside.
Since a and 3b are provided, the workability can be remarkably enhanced, and the occurrence of the bridge phenomenon and the adhesion of dirt can be reliably prevented.

Further, it is preferable to set the cross-sectional area of the liquid container to be dispensed so that a sufficient change in the liquid surface occurs as described above in the state where the liquid is inhaled by the dispensing amount.
When the cross-sectional area is large, the presence or absence of clogging is determined by inhaling the liquid to be dispensed by a predetermined amount that is larger than the dispensing amount, and only when it is determined that there is no clogging, the dispensing amount is dispensed again. The target liquid may be inhaled.

Further, instead of performing the above determination for each dispensing operation, the presence or absence of clogging is determined by inhaling the liquid to be dispensed by a predetermined amount before actually performing the dispensing operation, and the clogging is determined. If the liquid suction for dispensing is performed only when it is determined that the dispensing nozzle is not clogged, it can be reliably determined whether or not the dispensing nozzle is clogged, regardless of the cross-sectional area.

FIG. 6 is a central longitudinal cross-sectional view showing another example of the structure of the dispensing nozzle and the liquid storage part for dispensing. The difference from the example of the structure of FIG. 5 is that the electrodes 3a and 3b are connected to the dispensing nozzle 3. Instead of providing, a liquid level detection sensor 3d including a photo sensor is provided in the dispensing target liquid storage portion 3c.
Therefore, also in the case of this configuration example, whether or not clogging has occurred in the dispensing nozzle 3 based on whether or not the liquid surface has changed when the operation for sucking the liquid to be dispensed is performed. Can be determined. However, in the case of this configuration example, the liquid level of the liquid to be dispensed at the time of starting the operation for inhalation must be accurately set with respect to the liquid level detection sensor 3d. Since it is unnecessary to set the liquid level in the specific example of FIG. 5, it is preferable to adopt the configuration example of FIG.

FIG. 7 is a central longitudinal sectional view showing still another example of the structure of the dispensing nozzle and the dispensing target liquid storage portion.
3 is different from the configuration example in FIG.
It is only that an optical liquid level sensor 3e is provided instead of the above. This optical liquid level sensor 3e utilizes the fact that the intensity of reflected light changes depending on whether it is in contact with gas or in contact with liquid.

Therefore, even in the case of this configuration example, FIG.
It is possible to determine the presence or absence of clogging in the dispensing nozzle 3 as in the configuration example of.

[0033]

[Embodiment 3] FIG. 9 is a schematic view showing an example of the configuration of a dispensing nozzle system in which the abnormality detecting method in the dispensing device of the present invention is carried out. The dispensing nozzle 4, the syringe 5, and the cleaning liquid tank 6 are shown. And a communication conduit 7 communicating between them, a state in which the syringe 5 communicates with the dispensing nozzle 4, and a cleaning liquid tank 6
And a switching valve 8 for selectively controlling a state in which the switching valve 8 is communicated with. Therefore, the syringe 5 and the dispensing nozzle 4 are communicated with each other by the switching valve 8 and the syringe 5 is reciprocated, whereby the liquid to be dispensed can be sucked and discharged. Further, the switching valve 8 connects the syringe 5 and the cleaning liquid tank 6 to operate the syringe 5 in one direction, and then the switching valve 8 connects the syringe 5 and the dispensing nozzle 4 in order to operate the syringe 5 in the opposite direction. As a result, the cleaning liquid can be sucked from the cleaning liquid tank 6 and discharged through the dispensing nozzle 4 to clean the dispensing nozzle system.

FIG. 10 is an enlarged sectional view showing the dispensing nozzle 4 and the communication pipe line 7. The communication pipe line 7 is made of a light-transmissive material, and the communication pipe line 7 has a predetermined position ( A transmissive photosensor 9 including a light emitting element 9a and a light receiving element 9b is provided at a predetermined position close to the dispensing nozzle 4). FIG. 8 is a flow chart for explaining still another embodiment of the abnormality detecting method in the dispensing apparatus of the present invention, in which the dispensing nozzle 4 and the syringe 5 are communicated with each other in step SP1, and the air layer for liquid separation in step SP2. The syringe 5 is operated so as to form a liquid, and in step SP3 the syringe 5 is operated to suck the liquid to be dispensed. And step SP
In 4, the syringe 5 is further operated to inhale an amount of air corresponding to the difference between the dispensed amount and the amount determined based on the arrangement position of the photosensor 9. After that, step SP
In 5, it is determined whether gas or liquid is present at the corresponding position based on the output signal from the photosensor. When it is determined that gas is present, it is displayed in step SP6 that the dispensing nozzle 4 is clogged. After the process of step SP6 is performed, or when it is determined that the liquid is present in step SP5, the series of processes is ended as it is.

A more detailed description will be given with reference to FIG. 11 showing a liquid suction state. By performing the process of step SP2, an air layer is formed at the tip of the dispensing nozzle 4, as shown in FIG. 11 (A). Next, by performing the processing of step SP3, the liquid to be dispensed is sucked from the tip of the dispensing nozzle 4 as shown in FIG. 11 (B). After that, as the processing of step SP4 is performed, as shown in FIG.
Air is further sucked in from the tip of the liquid, and the liquid level of the liquid to be dispensed faces the photosensor 9 directly. Therefore, based on the output signal of the photo sensor 9, it can be determined that the dispensing nozzle 4 is not clogged. On the contrary, when the dispensing nozzle 4 is clogged, the air layer is expanded by operating the syringe 5, so that the air layer directly faces the photosensor 9. Therefore, it can be determined based on the output signal of the photo sensor 9 that the dispensing nozzle 4 is clogged.

As is clear from the above description, even if the dispensing amount of the liquid to be dispensed changes, clogging in the dispensing nozzle 4 is generated based on the output signal of the photo sensor 9 in the state where air is complementarily sucked. The presence or absence of can be reliably determined.

[0037]

[Embodiment 4] FIG. 12 is a flow chart for explaining still another embodiment of the abnormality detecting method in the dispensing apparatus of the present invention. After dispensing one kind of liquid to be dispensed, in step SP1. The syringe is operated to suck air to prevent the liquids from contacting each other, the counting of the number of detections of the air layer by the photosensor is started in step SP2, and in step SP3, at least the range where the liquid to be dispensed comes into contact is determined. Operate the syringe to inhale the cleaning solution in excess of the amount. Then, step SP4
At step SP5, the syringe is operated in reverse so as to discharge the inhaled cleaning liquid and the air layer, the counting of the number of detections of the air layer is stopped in step SP5, and the number of detections of the air layer is 2 times or 3 times in step SP6. It is determined whether or not the above. When it is determined in step SP6 that the number of detections of the air layer is three times or more, step SP
In step 7, it is displayed that dirt is attached, and the process of step SP1 is performed again. On the other hand, if it is determined in step SP6 that the number of times the air layer has been detected is two, the series of processes is ended.

Note that the method of FIG. 12 is, for example, as shown in FIGS.
It is performed based on a dispensing nozzle system of 0. More specifically, since not only the inner diameter of the dispensing nozzle but also the inner diameter of the communication conduit is set to be considerably small, for example, proteins contained in the liquid to be dispensed adhere to the inner wall of the communication conduit as dirt. there's a possibility that. Then, if dirt is attached, the air and the cleaning liquid will not smoothly flow, so that the one air layer becomes discontinuous despite the fact that there is one air layer in the dispensing nozzle. The present inventor has found that a number of air layers greater than the sum of the number of times of inhalation and the number of times of ejection is detected.
This example is based on the above findings,
By determining whether the number of detections of the air layer during the suction and the discharge of the cleaning liquid is once or twice or more, it is possible to determine whether or not the dirt is attached. Of course, when it is determined that dirt is attached, the dispensing nozzle system may be cleaned using the cleaning liquid in the cleaning liquid tank. Further, the above operation may be performed at the initial stage of power-on.

[0039]

[Embodiment 5] FIG. 13 is a flow chart for explaining still another embodiment of the abnormality detecting method in the dispensing apparatus of the present invention. In step SP1, the syringe and the washing liquid tank are communicated with each other, and in step SP2, the washing liquid is fed by the syringe. Inhale, start counting the number of times the photosensor detects the air layer in step SP3, and
4. Connect the syringe with the dispensing nozzle in step 4,
The cleaning liquid sucked into the syringe at P5 is discharged through the dispensing nozzle. Then, in step SP6, it is determined whether or not it is instructed to repeat the cleaning operation, and when it is instructed to repeat the cleaning operation, the process of step SP1 is performed again. On the contrary, if it is determined in step SP6 that it is instructed that the cleaning operation should not be repeated, the counting of the number of detections of the air layer by the photosensor is stopped in step SP7, and the air layer is detected in step SP8. It is determined whether or not the number of times of detection is 0, and if the number of times of detection is not 0, it is displayed in step SP9 that the liquid leakage has occurred, and the series of processes is ended. Of course, if it is determined in step SP8 that the number of times the air layer has been detected is 0, the series of processes is directly terminated.

Incidentally, the method of FIG. 13 is, for example, as shown in FIGS.
It is performed based on a dispensing nozzle system of 0. As is clear from the above description, steps SP1 to SP5
Since there is no process of intentionally introducing an air layer into the dispensing nozzle system in the processes up to, the number of counts of the air layer is 0 unless an abnormality occurs, and the number of counts other than 0 In case of, liquid leakage has occurred. Therefore, it is not necessary to provide a liquid leak sensor at every place where liquid leak may occur, and the liquid leak can be surely determined only by disposing the photosensor at a predetermined position of the communication conduit.

However, in this process, the same determination result is obtained when a liquid leak occurs and when the cleaning liquid tank is empty. Therefore, for example, the cleaning liquid tank should be sufficiently filled with the cleaning liquid in advance. Alternatively, by detecting that the cleaning liquid tank is not empty by using a weight sensor, a liquid level sensor, or the like, it is possible to reliably determine only the liquid leak.

[0042]

As described above, according to the first aspect of the invention, when the dispensing nozzle is made of a conductive material, the dispensing nozzle is divided at a predetermined position, and an insulating member is provided at the divided portion. On the contrary, when the dispensing nozzle is made of an insulating material, the dispensing nozzle is divided into three parts,
By interposing a conductive member in each section,
Since the electrode can be attached to the dispensing nozzle, the workability can be significantly improved as compared with the conventional example in which the sensor is attached to the inner surface of the dispensing nozzle, and the bridge phenomenon which has been a problem in the conventional example can be achieved. Since it is possible to prevent the influence in advance and to achieve accurate abnormality detection, and also to make the inner surfaces of the conductive and insulating parts flush with each other, it is possible to greatly reduce the adhesion of dirt caused by proteins and the like. As a result, it is possible to minimize the cleaning of the dispensing nozzle, and eventually to shorten the time required for inspection and the like as compared with the conventional example.

According to the invention of claim 2, it suffices to provide the sensor at a predetermined position on the outer surface of the dispensing nozzle, a solution containing portion to be dispensed, etc., and the workability is improved as compared with the conventional example in which the sensor is provided on the inner surface of the dispensing nozzle. Since the influence of the bridge phenomenon, which has been a problem in the conventional example, can be prevented in advance, accurate abnormality detection can be achieved, and further, the flushness of the inner surface of the dispensing nozzle can be maintained. Therefore, it is possible to significantly reduce the adhesion of stains caused by proteins, etc., to minimize the cleaning of the dispensing nozzle, and to shorten the time required for inspection, etc. as compared with the conventional example. Produce an effect.

According to the invention of claim 3, in addition to the effect of claim 2, even if the suction amount of the liquid changes, the liquid level detection position can be kept constant by complementarily changing the suction amount of the gas. Therefore, it is possible to easily deal with various dispensing amounts, and it is possible to ensure the detection of clogging of the dispensing nozzle. According to the invention of claim 4, it is not necessary to provide a sensor for directly detecting the dirt inside the dispensing nozzle system, and the suction operation and the discharge operation are performed by simply interposing an air layer for liquid separation, and at least two air There is a unique effect that it is possible to easily and surely detect dirt based only on whether or not a layer is detected.

According to the fifth aspect of the present invention, the air layer is detected while performing the suction operation and / or the discharge operation without interposing the air layer in order to clean the dispensing nozzle system and the like. In response to this, it is possible to determine that liquid leakage has occurred, and it is no longer necessary to separately provide a liquid leakage sensor at the location where liquid leakage may occur, which is a unique effect that the configuration can be greatly simplified. Play.

According to a sixth aspect of the invention, when the dispensing nozzle is made of a conductive material, the dispensing nozzle is sectioned at a predetermined position, and an insulating member is interposed in the section.
On the contrary, when the dispensing nozzle is made of an insulating material, the dispensing nozzle is divided into three parts, and a conductive member is interposed in each of the divided parts so that the electrode of the dispensing nozzle is Since the mounting can be achieved, the workability can be significantly improved as compared with the conventional example in which the sensor is mounted on the inner surface of the dispensing nozzle, and the influence of the bridge phenomenon, which is a problem in the conventional example, can be prevented. As a result, accurate abnormality detection can be achieved, and since the inner surfaces of the conductive and insulating portions can be made flush with each other, the adhesion of dirt caused by proteins etc. can be significantly reduced, and the dispensing nozzle's There is a particular effect that the cleaning can be minimized to the minimum, and that the time required for inspection and the like can be shortened as compared with the conventional example.

[Brief description of drawings]

FIG. 1 is a flowchart illustrating an embodiment of a method for detecting an abnormality in a dispensing device of the present invention.

FIG. 2 is a central longitudinal sectional view showing an example of the configuration of a dispensing nozzle in which the abnormality detecting method in the dispensing device of the present invention is carried out.

FIG. 3 is a vertical cross-sectional view showing another configuration example of the dispensing nozzle.

FIG. 4 is a flow chart for explaining another embodiment of the abnormality detecting method in the dispensing device of the present invention.

FIG. 5 is a central vertical cross-sectional view showing an example of the configuration of a dispensing nozzle and a dispensing target liquid storage unit in which the abnormality detecting method in the dispensing device of the present invention is carried out.

FIG. 6 is a central vertical cross-sectional view showing another configuration example of the dispensing nozzle and the dispensing target liquid storage portion.

FIG. 7 is a central vertical cross-sectional view showing still another configuration example of the dispensing nozzle and the dispensing target liquid storage portion.

FIG. 8 is a flow chart for explaining still another embodiment of the abnormality detecting method in the dispensing device of the present invention.

FIG. 9 is a schematic diagram showing an example of the configuration of a dispensing nozzle system in which the abnormality detecting method in the dispensing device of the present invention is carried out.

FIG. 10 is an enlarged cross-sectional view showing a dispensing nozzle and a communication conduit.

FIG. 11 is a diagram illustrating a liquid suction state.

FIG. 12 is a flow chart for explaining still another embodiment of the abnormality detecting method in the dispensing device of the present invention.

FIG. 13 is a flow chart for explaining still another embodiment of the abnormality detecting method in the dispensing device of the present invention.

[Explanation of symbols]

1, 2 dispensing nozzles 1a, 1b division parts 2d, 2e conductive members 3a, 3b electrodes 3d liquid level detection sensor 3e optical liquid level sensor 9 transmissive photosensor 10 abnormal indication signal output part

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshihiro Nishino 1000-2 Otani, Okamoto-cho, Kusatsu-shi, Shiga Daikin Industry Co., Ltd. Shiga Works (72) Inventor Koji Ogami 1000 Otani, Okamoto-cho, Kusatsu-shi, Shiga No. 2 Inside Daikin Industries, Ltd. Shiga Works

Claims (6)

[Claims] 1. A pair of electrodes (1a) having electrode gaps at predetermined positions of the dispensing nozzles (1) (2) corresponding to the dispensing amount.
(1b), (2d), and (2e) are provided in the axial direction of the dispensing nozzle to show that normal liquid suction cannot be performed in response to a large interelectrode resistance during liquid suction for dispensing. An abnormality detection method in a dispensing device, which is characterized by outputting an abnormality instruction signal. 2. A sensor (3a) (3b) (3d) (3e) (9) for detecting the liquid level of a liquid to be dispensed is provided at a predetermined position so that the sensor (3
a) (3b) (3d) (3e) (9) in response to the output signal, the dispensing device characterized by outputting an abnormality instruction signal indicating whether or not normal liquid suction is not possible Abnormality detection method. 3. The sensor (9) for detecting the liquid level of a liquid to be dispensed is provided at a predetermined position corresponding to a liquid amount larger than the maximum dispensing amount of the dispensing nozzle system. Abnormality detection method in dispensing device. 4. A sensor (9) for discriminating between a gas and a liquid is provided at a predetermined position of a dispensing nozzle system, and a suction operation and a discharge operation are performed to interpose an air layer for liquid separation, and these operations are performed. An abnormality detection method in a dispensing device, which outputs an abnormality instruction signal indicating dirt inside the dispensing nozzle system in response to detection of two or more air layers by a sensor (9) therein. 5. A sensor (9) for discriminating between a gas and a liquid is provided at a predetermined position of a dispensing nozzle system, and a suction operation and / or a discharge operation is performed in order to prevent an air layer for liquid separation from intervening. An abnormality detection signal is output in response to the detection of an air layer by the sensor (9) during these operations, and an abnormality detection signal is output to indicate an abnormality in the dispensing nozzle system. Method. 6. A pair of electrodes (1a) for making electrode gaps at predetermined positions of the dispensing nozzles (1) (2) corresponding to the dispensing amount.
(1b) (2d) (2e) are provided in the axial direction of the dispensing nozzle, and the electrodes (1a) (1b) (2d) (2
A pair of electrodes (1a) (1b) (2d) (2e) is formed to make the inner surface of e) flush with the inner surfaces of the dispensing nozzles (1) and (2). Dispensing characterized by including an abnormal signal output means (10) for outputting an abnormal instruction signal indicating that normal liquid suction is not performed in response to a large interelectrode resistance during liquid suction. Abnormality detection method in equipment.