JP2007322286A - Dispenser - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect the liquid surface contact of the probe actually brought into contact with a liquid sample without erroneously detecting the liquid surface contact of the probe when the liquid sample is dispensed using a plurality of probes. <P>SOLUTION: This dispenser includes a plurality of the probes 2a-2d for sucking and discharging the liquid sample, an AC generating part 7 for generating the AC voltage applied to each of a plurality of the probes 2a-2d, a switching part 8 for switching the application of AC voltage to the respective probes 2a-2d, liquid surface detection parts 9a-9d and a control part 12. The control part 12 performs not only control for successively switching the application of AC voltage to the respective probes in a time sharing manner with respect to the switching part 8 but also control for detecting the liquid surface contact of the probe to which AC voltage is applied and the liquid sample in synchronous relation to the control with respect to the liquid surface detection parts 9a-9d. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a dispensing apparatus that dispenses a liquid sample such as blood or body fluid using a plurality of probes, and in particular, detects a liquid surface contact between a probe and a liquid sample based on a change in capacitance of the probe. The present invention relates to a dispensing device having a liquid level detection function.

  2. Description of the Related Art Conventionally, an automatic analyzer for analyzing a specimen such as blood or body fluid biochemically or immunologically using a reagent has been proposed. Such an automatic analyzer includes a dispensing device that accurately collects a liquid sample such as a specimen or a reagent and dispenses it into a container in order to obtain an accurate analysis result. When dispensing a liquid sample, this dispensing apparatus detects contact between the probe that sucks or discharges the liquid sample and the liquid sample in the container, and controls the amount of probe penetration from the sample liquid surface to be constant. . By controlling the amount of probe penetration, the dispensing device can prevent the probe from leaving the liquid sample before aspirating the required amount of liquid sample, and can reliably dispense the required amount of liquid sample. . As such a dispensing apparatus, there is an apparatus having a capacitance type liquid level detection function for detecting a liquid level contact between a probe and a liquid sample based on a change in capacitance of the probe (for example, Patent Document 1). reference.).

JP 2003-57096 A

  By the way, if the conventional dispensing apparatus described above has a function of collecting a liquid sample from a plurality of containers using a plurality of probes, the liquid sample can be dispensed to a plurality of containers by a single dispensing operation. . In this case, the conventional dispensing device detects the change in the capacitance described above based on the detection signal output by the probe that has contacted the liquid sample among the plurality of probes, and the change in the capacitance. Based on this, the liquid level contact of this probe is detected.

  However, in the conventional dispensing device, when the liquid level contact of the plurality of probes is detected, the above-described detection signal interferes between a probe actually in liquid level contact and a nearby probe not in liquid level contact. Since there are many cases, there is a problem in that there is a possibility that a nearby probe that is not in liquid surface contact may be erroneously recognized as being in liquid surface contact (that is, erroneously detected).

  The present invention has been made in view of the above circumstances, and when dispensing a liquid sample using a plurality of probes, the liquid surface contact of the probe was actually contacted without erroneous detection. It aims at providing the dispensing apparatus which can detect the liquid level contact of a probe.

  In order to solve the above-described problems and achieve the object, a dispensing apparatus according to claim 1 applies an AC voltage to each probe of a plurality of probes that suck or discharge a liquid sample, and In a dispensing apparatus that detects liquid surface contact between each probe and the liquid sample based on a change in volume and dispenses the liquid sample using the plurality of probes, each probe of the plurality of probes Switching means for switching the application of the AC voltage to the switch, and control for sequentially switching the application of the AC voltage in a time-sharing manner, and detecting the liquid surface contact of the probe to which the AC voltage is applied in synchronization with the control. Control means for performing control.

  The dispensing apparatus according to claim 2 is characterized in that, in the above-mentioned invention, the probe for applying the AC voltage is any one of the plurality of probes.

  The dispensing apparatus according to claim 3 is characterized in that, in the above-mentioned invention, the probes to which the AC voltage is applied are a group of probes separated from each other by a predetermined distance or more among the plurality of probes.

  According to a fourth aspect of the present invention, in the above dispensing device, the control means enables a liquid level detection process for detecting a liquid level contact of the probe to which the AC voltage is applied and applies the AC voltage. Control for invalidating the liquid level detection process for detecting the liquid level contact of the remaining probes other than the probe is performed.

  The dispensing apparatus according to claim 5 is characterized in that, in the above-mentioned invention, the AC voltage is a sine wave voltage having a constant frequency band between the plurality of probes.

  According to the present invention, when a liquid sample is dispensed using a plurality of probes, a probe that is actually in contact with the liquid sample is not erroneously detected as a non-contact probe in liquid contact with the liquid sample. There exists an effect that the dispensing device which can detect a liquid level contact reliably is realizable.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a preferred embodiment of a dispensing device according to the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments.

  FIG. 1 is a block diagram schematically showing a configuration example of a dispensing apparatus according to an embodiment of the present invention. As shown in FIG. 1, the dispensing device 1 is configured to ascend or descend a plurality of probes 2a to 2d for aspirating / discharging a sample such as blood or body fluid or a liquid sample such as a reagent, and probes 2a to 2d, respectively. Drive units 4a to 4d, and a dispensing control unit 6 that controls the driving of the probes 2a to 2d and the drive units 4a to 4d in order to dispense a liquid sample into a container. In addition, the dispensing device 1 includes an AC generator 7 that outputs a predetermined AC voltage, a switching unit 8 that applies the AC voltage to a probe to be processed among the probes 2a to 2d, and probes 2a to 2d. A liquid level detection unit 9a for detecting liquid level contact between the liquid sample and the liquid sample, an input unit 10, a storage unit 11, and a control unit 12 for controlling the driving of each component of the dispensing apparatus 1; Have. Furthermore, the dispensing apparatus 1 has an electrode plate 114 in the vicinity of a rack 113 that houses sample containers 101a to 101d, for example.

  The probes 2a to 2d are conductor probes in which pipe lines for sucking or discharging a liquid sample are formed, and are held by the drive units 4a to 4d, respectively. The probes 2a to 2d are arranged in the vicinity of each other, for example, and each sample in the sample containers 101a to 101d densely stored in the rack 113 as shown in FIG.

  The drive units 4a to 4d hold the probes 2a to 2d, respectively, and drive the probes 2a to 2d to move up or down when dispensing a liquid sample. Specifically, for example, when collecting each sample in the sample containers 101a to 101d, the drive units 4a to 4d perform driving to lower the probes 2a to 2d toward the sample containers 101a to 101d, respectively. After the collection, the probe 2a to 2d that has aspirated the specimen is driven to rise.

  The dispensing control unit 6 controls the driving of the probes 2a to 2d and the driving units 4a to 4d in order to dispense the liquid sample into the container. Specifically, the dispensing control unit 6 controls the liquid sample suction operation and the discharge operation by the probes 2a to 2d and the ascending and descending driving of the probes 2a to 2d by the driving units 4a to 4d, and the liquid sample Into a container. In this case, the dispensing controller 6 individually controls the ascending drive and the descending drive of the probes 2a to 2d with respect to the drive units 4a to 4d. Thereby, the dispensing control unit 6 can raise or lower each of the probes 2a to 2d individually or simultaneously. The dispensing control unit 6 includes pipes 5a to 5d communicating with the probes 2a to 2d, respectively, and adjusts the pressures in the probes 2a to 2d via the pipes 5a to 5d. The suction operation and the discharge operation of the liquid sample by 2d are controlled. The dispensing control unit 6 collects each sample in the sample containers 101a to 101d, for example, by performing the suction / discharge control of the probes 2a to 2d and the drive control of the drive units 4a to 4d. Dispense into other test containers.

  The AC generator 7 generates an AC voltage, for example, a sine wave voltage in a predetermined frequency band. In this case, the AC generation unit 7 outputs the voltage signal S1 to the switching unit 8 as such an AC voltage. Note that the AC generator 7 may output a pulse voltage having a predetermined pulse waveform as the voltage signal S1.

  The switching unit 8 is for switching the application of the AC voltage to each probe of the probes 2a to 2d. Specifically, the switching unit 8 sequentially switches the electrical connection between the probes 2a to 2d and the AC generation unit 7, and switches on / off the AC voltage for the probes 2a to 2d. The switching unit 8 performs the AC voltage on / off switching operation in this way, and inputs, for example, the voltage signal S1 output from the AC generation unit 7 to any of the probes 2a to 2d.

  The liquid level detection units 9a to 9d are for performing a liquid level detection process for detecting a liquid level contact between the probe and the liquid sample by a capacitance method for the probe to be processed among the probes 2a to 2d. . The probe to be processed is a probe to which the voltage signal S1 is input in order to perform the liquid level detection process. For example, when the probes 2a to 2d are located in the vicinity of each other, One of them.

  The liquid level detector 9a detects a change in the capacitance of the probe 2a, and detects a liquid level contact between the probe 2a and the liquid sample based on the change in the capacitance. Similarly, the liquid level detectors 9b to 9d detect the liquid level contact between the probes 2b to 2d and the liquid sample, respectively, based on changes in the capacitances of the probes 2b to 2d. In this case, the liquid level detectors 9a to 9d have a constant frequency band of the AC voltage applied to any of the probes 2a to 2d between the probes. It is almost constant. This can suppress variations in the results of the liquid level detection processes performed by the liquid level detection units 9a to 9d.

  Here, the electrode plate 114 is connected to, for example, ground, and when the probes 2a to 2d are located at the origins of ascending and descending, the electrode plate 114 is disposed at a distance d0 from the probes 2a to 2d. The electrode plate 114 and the probes 2a to 2d form capacitors having capacitances C1 to C4, respectively. Further, the probes 2a to 2d are lowered toward the sample containers 101a to 101d so as to reduce the distance d0, for example, as shown in FIG. Ascending from the sample containers 101a to 101d so as to return to the position of d0. In this case, the capacitances C1 to C4 of the probes 2a to 2d change as the probes 2a to 2d move (that is, change in the distance d0). Specifically, the capacitances C1 to C4 increase as the probes 2a to 2d are lowered (that is, the distance d0 is decreased), respectively. In particular, the probes 2a to 2d are liquid samples such as the specimen containers 101a to 101d. When the liquid level comes into contact with each of the specimens, it rapidly increases.

  The liquid level detectors 9a to 9d detect each liquid level contact of the probes 2a to 2d based on such changes in capacitance of the probes 2a to 2d. Specifically, when the voltage signal S1 described above is input, the probes 2a to 2d output detection signals Sa to Sd corresponding to the capacitances C1 to C4, respectively. The liquid level detection units 9a to 9d receive the detection signals Sa to Sd, respectively, and detect changes in the capacitances C1 to C4 based on the received detection signals Sa to Sd, respectively. The liquid level detection units 9a to 9d detect the liquid level contact of the probes 2a to 2d based on the changes in the capacitances C1 to C4 using the threshold value of the liquid level detection process set in advance by the control unit 12, respectively. . In this case, the liquid level detection unit 9a detects the liquid level contact between the probe 2a and the liquid sample, for example, when the voltage value based on the detection signal Sa exceeds the threshold value of the liquid level detection process. Similarly, the liquid level detectors 9b to 9d detect the liquid level contact of the probes 2b to 2d based on the detection signals Sb to Sd and the threshold value of the liquid level detection process, respectively. The liquid level detection units 9 a to 9 d output the result of the liquid level detection process to the control unit 12.

  The input unit 10 is realized by using a keyboard or a mouse, information to be instructed to the control unit 12, processing conditions for liquid level detection processing by the liquid level detection units 9a to 9d, operating conditions for on / off switching operation by the switching unit 8, and the like Is input to the control unit 12. In this case, the input unit 10 inputs, for example, the above-described threshold value of the liquid level detection process as the processing condition of the liquid level detection process. In addition, the input unit 10 inputs switching time information that determines a time interval for sequentially switching the input of the voltage signal S1 to the probes 2a to 2d (that is, the application of the AC voltage described above) as the operating condition of the on / off switching operation. .

  The storage unit 11 accumulates information instructed to be written by the control unit 12, and outputs accumulated information instructed to be read out by the control unit 12 to the control unit 15. In this case, the storage unit 11 stores information input by the input unit 10, such as processing conditions for liquid level detection processing and operating conditions for on / off switching operation. In addition, the storage unit 11 stores the results of the liquid level detection processing performed by the liquid level detection units 9a to 9d.

  The control unit 12 controls each operation of the components of the dispensing device 1, such as the dispensing control unit 6, the switching unit 8, the liquid level detection units 9 a to 9 d, the input unit 10, and the storage unit 11, and information input / output. . In this case, for example, the control unit 12 determines the time interval of the on / off switching operation of the switching unit 8 based on the switching time information, and controls the switching unit 8 to sequentially execute the on / off switching operation with delay for each time. Against. By controlling the on / off switching operation in this way, the control unit 12 can control the operation of the switching unit 8 so as to sequentially switch the application of the AC voltage to the probes 2a to 2d in a time division manner.

  In addition, the control unit 12 notifies the liquid level detection processing threshold value input by the input unit 10 to the liquid level detection units 9a to 9d, and then the liquid level detection unit 9a in synchronization with the above-described control of the on / off switching operation. Control the operation of the liquid level detection process by ~ 9d. Specifically, the control unit 12 enables the liquid level detection process of the probe to be processed among the probes 2a to 2d and invalidates the liquid level detection process of the remaining probes other than the probe to be processed. In this manner, the processing operations of the liquid level detection units 9a to 9d are controlled. In this case, the control unit 12 synchronizes with the above-described control of the on / off switching operation so that the probe to be processed in the liquid level detection process and the probe to which the voltage signal S1 is input are surely matched. The liquid level detection processing of the surface detection units 9a to 9d is sequentially switched between valid and invalid.

  Next, the control for sequentially executing the on / off switching operation in a time division manner and the control for sequentially executing the liquid level detection processing of the probe to be processed in synchronism with this will be described in detail. FIG. 2 is a schematic diagram for explaining the control for sequentially executing the on / off switching operation in a time-sharing manner. In FIG. 2, a sine wave voltage having a voltage amplitude V (that is, a voltage value V) is illustrated as the voltage signal S1 described above.

  As shown in FIG. 2, the control unit 12 determines a time interval M when the on / off switching operation is sequentially performed in a time division manner based on the switching time information input by the input unit 10, and this time interval M Control for sequentially executing the on / off switching operation with a delay is performed on the switching unit 8. Specifically, the control unit 12 controls the switching unit 8 to sequentially execute the on / off switching operation at time t0, time t1, time t2, and time t3 with a time interval M, for example.

  By controlling the on / off switching operation, the switching unit 8 establishes an electrical connection between the probes 2a to 2d and the AC generator 7 so that the voltage signal S1 is not simultaneously applied to two or more of the probes 2a to 2d. Switch sequentially in time division. Specifically, the switching unit 8 electrically connects the probe 2a and the AC generator 7 at a time interval M from time t0 to time t1, and connects the probe 2b to the probe 2b at time interval M from time t1 to time t2. The AC generator 7 is electrically connected, the probe 2c and the AC generator 7 are electrically connected at a time interval M from time t2 to time t3, and the probe at a time interval M from time t3 to time t4. 2d and the AC generator 7 are electrically connected. The switching unit 8 inputs the voltage signal S1 to any one of the probes 2a to 2d at time t0 to t4.

  Note that the controller 12 controls the on / off switching operation after the time t4 as in the case of the times t0 to t4 described above. As a result, the switching unit 8 performs the on / off switching operation with a delay for each time interval M even after the time t4, and sequentially switches the input of the voltage signal S1 to the probes 2a to 2d, that is, the application of the AC voltage, in a time division manner.

  On the other hand, as described above, the control unit 12 performs operation control to enable or disable the liquid level detection processing of the liquid level detection units 9a to 9d in synchronization with the control of the on / off switching operation. In this case, the control unit 12 enables the liquid level detection processing by the liquid level detection unit (any one of the liquid level detection units 9a to 9d) for detecting the liquid level contact of the probe to be processed. Control which invalidates the liquid level detection process by another liquid level detection part is performed. In this way, by performing control to enable or disable the liquid level detection process, the control unit 12 performs the liquid level detection process on any of the liquid level detection units 9a to 9d in synchronization with the above-described on / off switching operation. The probe to be processed is switched sequentially. Specifically, when the probe 2a is a probe to be processed, for example, the control unit 12 enables the liquid level detection processing by the liquid level detection unit 9a for detecting the liquid level contact of the probe 2a, and At the same time, control is performed to invalidate the liquid level detection processing by the other liquid level detection units 9b to 9d. Such operation control of the liquid level detection processing is performed in substantially the same manner as in the case of the above-described probe 2a even when any of the other probes 2b to 2d is a probe to be processed.

  In such operation control of the liquid level detection process, as described above, the control unit 12 reliably matches the probe to be processed in the effective liquid level detection process with the probe to which the voltage signal S1 is input. That is, the control unit 12 enables the liquid level detection processing of the liquid level detection unit 9a for detecting the liquid level contact of the probe 2a, for example, at a time interval M from time t0 to time t1 shown in FIG. The liquid level detection unit 9b for detecting the liquid level contact of the probe 2b in the time interval M from time t1 to time t2 by invalidating the liquid level detection processing of the other liquid level detection units 9b to 9d. While enabling the detection process, the liquid level detection processes of the other liquid level detection units 9a, 9c, 9d are disabled. In addition, the control unit 12 enables the liquid level detection processing of the liquid level detection unit 9c for detecting the liquid level contact of the probe 2c in the time interval M from the time t2 to the time t3. The liquid level detection process of the liquid level detection unit 9d for detecting the liquid level contact of the probe 2d at the time interval M from the time t3 to the time t4 is disabled by invalidating the liquid level detection process of the detection units 9a, 9b, and 9d. While enabling it, the liquid level detection process of the other liquid level detection parts 9a-9c is invalidated.

  By the operation control of the liquid level detection process by the control unit 12, the liquid level detection units 9a to 9d do not simultaneously perform the liquid level detection process for two or more of the probes 2a to 2d located in the vicinity of each other. The liquid level detection process is performed on the probe to be processed which is one of the probes 2a to 2d. FIG. 3 is a schematic diagram for explaining the operation of detecting the liquid level contact of the probe to be processed. As shown in FIG. 3, for example, the probes 2a and 2b are lowered toward the sample containers 101a and 101b while increasing the capacitances C1 and C2, respectively, and are located at a distance d1 from the electrode plate 114. At the position of this distance d1, the probe 2a is in liquid surface contact with the sample in the sample container 101a, and the probe 2b is not in contact with the sample in the sample container 101b. In this state, the capacitance C1 of the probe 2a increases rapidly due to the liquid level contact with the specimen.

  Here, when the control unit 12 controls the above-described on / off switching operation and inputs the voltage signal S1 to the probe 2a, the control unit 12 validates the liquid level detection processing of the liquid level detection unit 9a in synchronization with the control of the on / off switching operation. At the same time, the liquid level detection processing of the liquid level detection units 9b to 9d is invalidated. In this case, the probe 2a is the probe to be processed as described above, and outputs a detection signal Sa to the liquid level detection unit 9a in response to the input voltage signal S1. Since the liquid level detection process is enabled by the operation control of the control unit 12, the liquid level detection unit 9a performs the liquid level detection process based on the detection signal Sa and detects the liquid level contact of the probe 2a. To do.

  At the same time, the probes 2a and 2b are located close to each other as shown in FIG. 3, so that a capacitor is formed, and the detection signal Sa is received by the probe 2b. For this reason, the detection signal Sa is also output to the liquid level detector 9b via the probe 2b. However, as described above, since the liquid level detection process is disabled by the control unit 12 in the liquid level detection unit 9b, the liquid level detection process is not performed using the detection signal Sa. The liquid level contact of the probe 2b that has not been detected is not erroneously detected.

  As described above, the control unit 12 performs the on / off switching operation and the control of the liquid level detection process in synchronization, so that the liquid level detection units 9a to 9d erroneously perform the liquid level contact of the probe that is not actually in liquid level contact. Without detection, the liquid level detection processing of the probe to be processed (that is, any of the probes 2a to 2d to which the voltage signal S1 is input) can be reliably performed.

  The control unit 12 can reliably acquire the result of each liquid level detection process for the probes 2a to 2d located in the vicinity of each other, and the operation of the dispensing control unit 6 can be performed using the acquired result of the liquid level detection process. Control. Specifically, when the control unit 12 recognizes that the probe to be processed is in liquid surface contact based on the obtained result of the liquid level detection process, the control unit 12 instructs the dispensing control unit 6 on the processing target. An instruction is given to perform a descending drive or an ascending drive that keeps the amount of penetration of the probe from the liquid level constant. Accordingly, the dispensing control unit 6 can control the ascending drive or descending drive of the probes in contact with the liquid level among the probes 2a to 2d, and can control the amount of the probe that has entered from the liquid level to be constant.

  In this way, by making the probe sink amount constant, the dispensing control unit 6 can prevent the probe from separating from the liquid sample before aspirating the required amount of the liquid sample, and ensure that the required amount of the liquid sample is secured. Can be dispensed into. At the same time, since the dispensing control unit 6 can make the contact ranges of the probes 2a to 2d with the liquid sample constant, it is possible to suppress contamination between the liquid samples when the dispensing operation is performed.

  Next, an application example of the dispensing device 1 according to the embodiment of the present invention will be described. Such a dispensing apparatus 1 can reliably perform a dispensing operation of a liquid sample such as a reagent or a specimen as described above, and is suitable for an automatic analyzer that needs to dispense a required amount of a liquid sample accurately. Dispensing device. FIG. 4 is a schematic diagram schematically showing a configuration example of an automatic analyzer to which the dispensing device 1 is applied. The automatic analyzer 100 analyzes a specimen biochemically or immunologically using a reagent. As shown in FIG. 4, the dispensing device 1 109, the transport table 104, the stirring unit 105, the analysis Unit 106, cleaning unit 107, and reagent table 108.

  The dispensing device 1 has an arm 3 in which the above-described driving units 4a to 4d are built. The arm 3 repeatedly rotates between the transfer table 104 and the rack 113. The dispensing apparatus 1 rotates the arm 3 to the rack 113 side, and collects each sample in the sample containers 101a to 101d using the probes 2a to 2d as described above. Thereafter, the dispensing apparatus 1 rotates the arm 3 toward the test containers 102a to 102d on the transport table 104, and dispenses the specimens thus collected using the probes 2a to 2d to the test containers 102a to 102d, respectively. To do. In this case, as described above, the dispensing apparatus 1 can reliably dispense a necessary amount of the sample into the test containers 102a to 102d.

  For example, the test tables 102a to 102d are arranged in four rows along the transport direction, and the transport table 104 rotates and transports the test containers 102a to 102d in each row in a predetermined direction. In this case, for example, the test containers 102a to 102d into which the specimens are dispensed are sequentially transported in the order of the stirring unit 105, the analysis unit 106, and the cleaning unit 107.

  The reagent table 108 and the dispensing device 109 are arranged in the vicinity of the transfer table 104. The reagent table 108 has a plurality of reagent containers 103 in which reagents mixed in the specimen are put, and the reagent containers 103 are rotated and sequentially conveyed to the vicinity of the dispensing device 109. The dispensing device 109 has an arm 110 that holds the same probe 111 as the probes 2a to 2d, and performs a dispensing operation substantially similar to that of the dispensing device 1 described above. The dispensing device 109 collects the reagent in the reagent container 103 using the arm 110 and the probe 111, and dispenses the reagent into the test containers 102a to 102d before being transported to the stirring unit 105. Thus, the test containers 102 a to 102 d in which the sample and the reagent are mixed are conveyed to the stirring unit 105.

  The stirring unit 105 stirs the liquid samples in the test containers 102a to 102d. By such a stirring process, the specimen and the reagent in the test containers 102a to 102d are uniformly mixed. Thereafter, the test containers 102 a to 102 d subjected to the stirring process are transported to the analysis unit 106.

  The analysis unit 106 analyzes, for example, components of the liquid sample in the test containers 102a to 102d using light of a predetermined wavelength band. The analysis unit 106 transmits the analysis result of the liquid sample to a data storage unit (not shown) of the automatic analyzer 1 or a host computer (not shown). This makes it possible to obtain a necessary analysis result for such a liquid sample. Thereafter, the test containers 102 a to 102 d subjected to such analysis processing are transported to the cleaning unit 107.

  The cleaning unit 107 discharges the liquid sample (that is, the mixed solution of the reagent and the specimen) in the test containers 102a to 102d on which the analysis process by the analysis unit 106 described above is performed, and cleans the test containers 102a to 102d. Thereafter, the test containers 102a to 102d subjected to the cleaning process are transported again to the vicinity of the dispensing apparatus 1 and reused. Depending on the examination contents of the specimen, the used test containers 102a to 102d may be discarded after one analysis process is performed.

  Thus, the automatic analyzer 100 to which the dispensing apparatus 1 is applied can accurately dispense a required amount of liquid sample and acquire an accurate analysis result. Therefore, the automatic analyzer 100 is suitable as an automatic analyzer for analyzing a specimen biochemically or immunologically by applying the dispensing apparatus 1 to a liquid sample dispensing mechanism.

  In the embodiment of the present invention, the probes 2a to 2d are arranged in the vicinity of each other, and the probe to be processed on which the liquid level detection process described above is performed is sequentially switched to any one of the probes 2a to 2d. However, the present invention is not limited to this, and when a plurality of probes provided in the dispensing apparatus 1 are separated from each other by a predetermined distance or more, such a probe group is used as a probe to be processed. In addition to the sequential switching, the liquid level detection processing may be performed in parallel for each switched probe to be processed. In this case, the control unit 12 controls the on / off switching operation of the switching unit 8 so as to simultaneously apply the AC voltage to the probe groups separated from each other by a predetermined distance among the probes 4a to 4d, and in synchronization therewith, In this way, the processing operations of the liquid level detection units 9a to 9d are controlled so that the liquid level detection processing is performed in parallel on the plurality of probes to which the AC voltage is applied. Here, since each probe of this probe group is arrange | positioned mutually more than predetermined distance, when performing the dispensing operation | movement mentioned above, the detection signal mentioned above is not mutually received between each probe.

  FIG. 5 is a schematic diagram for explaining the control of the on / off switching operation when an AC voltage is simultaneously applied to a plurality of probes. For example, if the probes 2a and 2c among the probes 2a to 2d are arranged apart from each other by a predetermined distance and the probes 2b and 2d are arranged apart from each other by a predetermined distance, the control unit 12 is shown in FIG. As described above, the on / off switching operation of the switching unit 8 is controlled so that the AC voltage is simultaneously applied to the probes 2a and 2c or the probes 2b and 2d. In this case, the switching unit 8 sequentially switches the application of the AC voltage to the probes 2a to 2d in a time division manner so that the AC voltage is simultaneously applied to the probes 2a and 2c or the probes 2b and 2d. Specifically, for example, the switching unit 8 performs an on / off switching operation so that the voltage signal S1 is simultaneously input to the probes 2a and 2c at the time interval M from time t0 to t1, and at the time interval M from time t1 to t2. An on / off switching operation is performed so that the voltage signal S1 is simultaneously input to the probes 2b and 2d. Thereafter, after the time t2, the switching unit 8 sequentially repeats the same on / off switching operation as in each time interval M between the times t0 to t2.

  In synchronization with the on / off switching operation, the control unit 12 enables the liquid level detection process for a plurality of probes to which an AC voltage is applied, that is, the probe to be processed, and disables the liquid level detection process for the remaining probes. Is performed on the liquid level detection units 9a to 9d. Specifically, for example, the control unit 12 enables the liquid level detection processing of the liquid level detection units 9a and 9c in the time interval M from time t0 to t1, and the liquid level of the other liquid level detection units 9b and 9d. The detection process is disabled, and the liquid level contact of the probes 2a and 2c to which the AC voltage is applied can be detected in parallel. In addition, the control unit 12 enables the liquid level detection processing of the liquid level detection units 9b and 9d and invalidates the liquid level detection processing of the other liquid level detection units 9a and 9c in the time interval M from time t1 to t2. The liquid level contact of the probes 2b and 2d to which the AC voltage is applied can be detected in parallel. The controller 12 repeats the operation control of the liquid level detectors 9a to 9d after the time t2 as in the case of each time interval M between the times t0 to t2.

  Thus, by controlling the operation of the switching unit 8 and the liquid level detection units 9a to 9d, the control unit 12 can reduce the time spent until the liquid level detection process of all the probes of the dispensing device 1 is repeated. Thereby, even if the dispensing apparatus 1 is provided with a larger number of probes (for example, five or more), the elapsed time until the liquid level detection process for all the probes is repeated is reduced to a small number, for example, 2 to 4 probes. It can be suppressed to the same level as when it is provided, and the above-described dispensing operation can be performed smoothly without causing erroneous detection of liquid level contact.

  In the embodiment of the present invention, the case where four probes for aspirating or discharging a liquid sample are illustrated, but the present invention is not limited to this, and a plurality of such probes are provided. It may be a pouring device.

  In the embodiment of the present invention, the liquid level detection unit is provided for each probe. However, the present invention is not limited to this, and each liquid level contact of a plurality of probes is detected for each probe. One or more liquid level detection units may be provided. In this case, the operation of the liquid level detection unit is controlled by the control unit 12 so as to perform only the liquid level detection process of the probe to be processed to which the AC voltage is applied.

  Furthermore, in the embodiment of the present invention, the case where the present invention is applied as a dispensing device for dispensing a sample to an automatic analyzer that analyzes the sample biochemically or immunologically has been exemplified. Is not limited to this, and may be applied to an automatic analyzer as a dispensing device for dispensing a liquid sample such as a reagent.

  Further, in the embodiment of the present invention, the application of the AC voltage is sequentially switched for a plurality of probes in a fixed switching order. However, the present invention is not limited to this, and the AC for the plurality of probes is not limited thereto. The switching order of voltage application may be a desired order. In this case, for example, among the plurality of probes provided in the dispensing device, the application of the alternating voltage to each probe is performed in a time-sharing manner so that the alternating voltage is preferentially applied to the probe that rises or falls during the dispensing operation. You may switch sequentially.

  As described above, in the embodiment of the present invention, the application of the AC voltage to each probe of a plurality of probes that suck or discharge the liquid sample is sequentially switched in a time-sharing manner, and is synchronized with the switching operation of the application of the AC voltage. Thus, the liquid level contact between the probe to which the AC voltage is applied and the liquid sample is sequentially detected. For this reason, when detecting each liquid level contact of a plurality of probes for dispensing a liquid sample, the probe to be processed in the liquid level detection process is sequentially switched in a time-sharing manner, and the detection output by the probe to be processed is detected. Interference between the signal and the detection signal of the remaining probe in the vicinity can be prevented, so that the liquid sample is actually contacted with the liquid sample without erroneously detecting that the non-contact probe is in contact with the liquid surface. It is possible to realize a dispensing device that can reliably detect the liquid surface contact of the probe.

It is a block diagram which shows typically the example of 1 structure of the dispensing apparatus which is embodiment of this invention. It is a schematic diagram for demonstrating the control which performs on-off switching operation | movement sequentially by a time division. It is a schematic diagram for demonstrating the operation | movement which detects the liquid level contact of a probe. It is a schematic diagram which shows typically the example of 1 structure of the automatic analyzer which applied the dispensing apparatus concerning this invention. It is a schematic diagram for demonstrating control of the on-off switching operation | movement in the case of applying an alternating voltage to a some probe simultaneously.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,109 Dispensing apparatus 2a-2d, 111 Probe 3,110 Arm 4a-4d Drive part 5a-5c Pipe line 6 Dispensing control part 7 AC generating part 8 Switching part 9a-9d Liquid level detection part 10 Input part 11 Memory | storage Section 12 Control section 100 Automatic analyzer 101a to 101d Sample container 102a to 102d Test container 103 Reagent container 104 Transport table 105 Stirring section 106 Analyzing section 107 Washing section 108 Reagent table 113 Rack 114 Electrode plate

Claims (5)

An AC voltage is applied to each probe of a plurality of probes that suck or discharge a liquid sample, and each liquid surface contact between each probe and the liquid sample is detected based on a change in capacitance of each probe, In a dispensing apparatus for dispensing the liquid sample using the plurality of probes,
Switching means for switching application of the AC voltage to each of the plurality of probes;
A control means for performing control for sequentially switching the application of the AC voltage in a time-sharing manner, and performing control for detecting the liquid surface contact of the probe to which the AC voltage is applied in synchronization with the control;
A dispensing device characterized by comprising:   The dispensing apparatus according to claim 1, wherein the probe that applies the AC voltage is any one of the plurality of probes.   The dispensing apparatus according to claim 1, wherein the probe that applies the AC voltage is a group of probes that are separated from each other by a predetermined distance or more among the plurality of probes.   The control means enables the liquid level detection process for detecting the liquid level contact of the probe to which the AC voltage is applied and detects the liquid level contact of the remaining probes other than the probe to which the AC voltage is applied. The dispensing apparatus according to claim 1, wherein control for invalidating the detection process is performed.   The dispensing apparatus according to claim 1, wherein the AC voltage is a sine wave voltage having a constant frequency band between the plurality of probes.

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