Temperature adjustment device and sample processing device

Abstract

Provided is a temperature adjustment device capable of appropriately detecting equipment abnormalities such as abnormalities of a Peltier element and an element temperature sensor, and the service life of the Peltier element. The temperature adjustment device comprises: a temperature adjustment mechanism that comprises a Peltier element and can change the temperature of an object; an element temperature sensor that detects the temperature of the Peltier element; and a control unit that controls the temperature adjustment mechanism. The control unit comprises: a resistance value calculation unit that periodically acquires resistance values of the Peltier element in a state where an AC current is superimposed on a DC current for driving the Peltier element; and an abnormality determination unit that determines an equipment abnormality on the basis of a first resistance value acquired in the present instance by the resistance value calculation unit and a second resistance value acquired before the present instance.

Description

Temperature control device and sample processing device

[0001] The present disclosure relates to a temperature adjustment device including a Peltier element and an element temperature sensor that detects the temperature of the Peltier element, and to a sample processing device including the temperature adjustment device.

[0002] Conventionally, temperature control devices (temperature control systems) that feed back the temperature measured by a temperature sensor and control a Peltier element or other heat source to match this with a target temperature have been used in many fields. Some of these temperature control devices have a function to detect abnormalities or malfunctions in the device.

[0003] Patent Document 1 describes a method for measuring the AC resistance of a thermoelectric device to provide early indication of device failure. Patent Document 2 describes a method for determining whether the relationship between the actual temperature of an object and the detected temperature value is appropriate based on whether the variation in the detected temperature value is greater than an allowable temperature deviation in a temperature adjustment device. Patent Document 3 describes detecting abnormalities or performance degradation in a temperature adjustment unit by determining an initial value for a control signal input to a temperature adjustment element and comparing the current control signal value with an abnormality determination threshold determined from this initial value.

[0004] Japanese Patent No. 5996613 Japanese Patent Application Laid-Open No. 2023-45819 Japanese Patent No. 6286539

[0005] However, Patent Document 1 does not disclose a means for detecting an abnormality in the temperature sensor of the thermoelectric device. Furthermore, the techniques disclosed in Patent Documents 2 and 3 require that the environmental temperature in which the temperature control device is used be constant, and there is a risk that the advantage of the temperature control device, which feedback controls the value of the element temperature sensor that detects the temperature of the Peltier element, may not be fully utilized.

[0006] Furthermore, in a temperature control device, if the element temperature sensor that detects the temperature of the Peltier element malfunctions or peels off, or if the temperature measured by the element temperature sensor deviates from the actual temperature due to condensation, this may not be detected and abnormal temperature control may continue.

[0007] For example, in pathology testing, biological samples such as tissues and blood are placed on a glass slide and heated and cooled in combination with a reagent to stain specific tissues. In recent years, sample processing devices that automate this process have been developed. Consideration is being given to using Peltier elements, which can heat and cool by switching the polarity of the applied voltage, as a heat source for these sample processing devices.

[0008] In a temperature control device mounted on such a sample device, if an abnormality in the element temperature sensor that detects the temperature of the Peltier element cannot be properly detected, there is a risk that the staining process for each slide glass cannot be properly performed.

[0009] Furthermore, Peltier elements are known to deteriorate during the temperature control cycle, and unless the lifespan of the Peltier element can be determined in advance, there is a risk of temperature control errors occurring at unexpected times.

[0010] One object of the present disclosure is to provide a temperature control technology that can appropriately detect equipment abnormalities such as abnormalities in a Peltier element and an element temperature sensor, and the end of the life of a Peltier element.

[0011] The temperature control device of the present disclosure that solves the above problem is a temperature control device that includes a temperature control mechanism that has a Peltier element and an element temperature sensor that detects the temperature of the Peltier element and can change the temperature of an object, and a control unit that controls the temperature control mechanism, wherein the control unit includes a resistance value calculation unit that periodically obtains the resistance value of the Peltier element while an AC current is superimposed on a DC current for driving the Peltier element, and an abnormality determination unit that determines whether or not there is an equipment abnormality based on a first resistance value currently obtained by the resistance value calculation unit and a second resistance value obtained previously.

[0012] According to the present disclosure, it is possible to provide a temperature control technology that can appropriately detect equipment abnormalities such as abnormalities in Peltier elements and element temperature sensors, and the end of the life of a Peltier element.

[0013] 1 is a plan view showing an overview of a sample processing apparatus including a temperature adjustment device of an embodiment; FIG. 2 is a front view showing an overview of a sample processing apparatus including a temperature adjustment device of an embodiment; FIG. 3 is a cross-sectional view showing an example of the configuration of a disk of a sample processing apparatus according to an embodiment; FIG. 4 is a schematic diagram showing a system of a sample processing apparatus including a temperature adjustment device of an embodiment; FIG. 5 is a block diagram showing the configuration of a temperature adjustment device of an embodiment; FIG. 6 is a diagram showing an example of a resistance temperature characteristic table of a Peltier element; FIG. 7 is a flowchart showing an example of a method for detecting an equipment abnormality using a temperature adjustment device of an embodiment; FIG. 8 is a graph showing an example of a change in the resistance value of a Peltier element depending on the number of temperature adjustment cycles; FIG. 9 is a graph showing an example of a change in the resistance value of a Peltier element depending on the number of temperature adjustment cycles;

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In all drawings for explaining the embodiments, components having the same functions are designated by the same reference numerals, and repeated explanations thereof will be omitted. In the following embodiments, explanations of identical or similar parts will not be repeated unless particularly necessary.

[0015] The X, Y, and Z directions described in the embodiments intersect and are orthogonal to each other. In the embodiments, the Z1 direction is described as the upward direction of a structure. The terms "plan view" and "plan view" used in the description of the embodiments refer to a plane defined by the X1 or X2 direction and the Y1 or Y2 direction, and the plane is viewed from the Z1 or Z2 direction.

[0016] <Configuration of Sample Processing Apparatus> First, the configuration of a sample processing apparatus 100 equipped with a temperature control apparatus (which may also be referred to as a temperature control system) according to one embodiment will be described using Figures 1 to 4. It is assumed that a sample to be processed is placed on a glass slide 1 used in the sample processing apparatus 100 described below. This sample is, for example, a biological sample such as tissue used in a pathological examination. In the following description, expressions such as "performing a staining process on the glass slide 1" mean "performing a staining process on the sample on the glass slide 1."

[0017] As shown in FIGS. 1 and 2, the sample processing apparatus 100 includes a supply unit 10, a storage unit 11, a transport unit 20, a staining unit 30, a memory unit 50, and an operation unit 51.

[0018] The supply unit 10 is provided for storing the slide glasses 1 before staining, i.e., the slide glasses 1 to be supplied to the staining unit 30. A tray 12 is provided inside the supply unit 10. A plurality of slide glasses 1 can be loaded on the tray 12. When a new staining process is to be performed, the tray 12 is moved in the Y1 direction from a predetermined standby position, and after a new slide glass 1 is loaded on the tray 12 at the destination, the tray 12 is moved in the Y2 direction to the original standby position.

[0019] The storage unit 11 is provided to store the slide glasses 1 after staining, i.e., the slide glasses 1 carried out from the staining unit 30. A tray 13 is provided inside the storage unit 11. The tray 13 can hold a plurality of slide glasses 1. When collecting the slide glasses 1 after staining, the tray 13 is moved in the Y1 direction to a predetermined collection position, the stained slide glasses 1 are stored in the tray 13, and then the tray 13 is moved in the Y2 direction to its original position.

[0020] The transport unit 20 is provided to transport the slide glass 1 between the supply unit 10 and the storage unit 11 and the staining unit 30. The transport unit 20 includes a grip portion 21 that can grip the slide glass 1. The transport unit 20 grips the slide glass 1 stored in the supply unit 10 with the grip portion 21 and transports the gripped slide glass 1 to the staining unit 30. After the sample has been stained in the staining unit 30, the transport unit 20 grips the slide glass 1 on which the sample is placed with the grip portion 21 and transports the gripped slide glass 1 from the staining unit 30 to the storage unit 11.

[0021] After the slide glass 1 is carried in from the supply unit 10, the staining unit 30 performs a staining process on the sample on the slide glass 1. The staining method used in the staining unit 30 is, for example, IHC staining or ISH staining.

[0022] A rotatable disk 31 is provided inside the staining unit 30. A plurality of stages 32 are installed on the disk 31. One slide glass 1 can be placed on each stage 32. A temperature adjustment mechanism 36 is provided on each stage 32. The temperature adjustment mechanism 36, which will be described in detail later, constitutes part of the temperature adjustment device 200 of this embodiment and can change the temperature of the stage 32. The temperature adjustment device 200, including the temperature adjustment mechanism 36, heats or cools the stage 32. When the temperature of the stage 32 is changed by the temperature adjustment mechanism 36, the temperature of the slide glass 1 placed on the stage 32 also changes, and accordingly, the temperature of the sample on the slide glass also changes.

[0023] A temperature sensor 40 and a humidity sensor 41 are provided inside the staining unit 30. The temperature sensor 40 is provided around the stage 32 and detects the temperature around the stage 32 (hereinafter referred to as the ambient temperature). The humidity sensor 41 is provided around the stage 32 and detects the humidity around the stage 32 (hereinafter referred to as the ambient humidity). The temperature sensor 40 and humidity sensor 41 may be provided as needed and are not essential components.

[0024] Although not shown, nozzles for supplying chemical solutions such as buffer solution, reagent, and cleaning solution required for the staining process are provided around the periphery of the disk 31. The required chemical solutions are supplied onto the slide glass 1 from the nozzles according to a preset protocol.

[0025] An example of the configuration of the disk 31 will be described below with reference to Fig. 3. Fig. 3 is a cross-sectional view showing a portion of the disk 31. As shown in Fig. 3, the disk 31 has, for example, a plurality of stages (holders) 32, a heat spreader 34, a fixing base 35, a temperature adjustment mechanism 36, a heat conduction plate 37, and a heat sink 38.

[0026] The stage 32 is a member that holds the slide glass 1 and the heat spreader 34. The fixing base 35 is a member that holds the stage 32. The stage 32 and the fixing base 35 are made of, for example, plastic or a resin material such as polycarbonate resin.

[0027] The slide glass 1 is placed on a heat spreader 34. The heat spreader 34 is provided to uniformly distribute the temperature across the surface of the slide glass 1. The area of ​​the heat spreader 34 is preferably equal to or larger than the area of ​​the slide glass 1. The heat spreader 34 is formed of, for example, copper or a metal material containing copper or aluminum as its main component.

[0028] A temperature adjustment mechanism 36 functioning as a temperature control device 200 is provided below the heat spreader 34. The temperature adjustment mechanism 36 adjusts the temperature of one slide glass 1 placed on each stage 32 to a desired temperature. In the example of FIG. 3 , the disk 31 has multiple stages 32, multiple heat spreaders 34, and multiple temperature adjustment mechanisms 36, and is capable of placing multiple slide glasses 1 on it. In the configuration of this embodiment, the temperature of each slide glass 1 can be adjusted individually by each temperature adjustment mechanism 36.

[0029] A heat conduction plate 37 is provided below the fixed base 35 and the temperature adjustment mechanism 36. The heat conduction plate 37 connects the temperature adjustment mechanism 36 to the heat sink 38 and is provided to facilitate the dissipation of heat from the temperature adjustment mechanism 36 to the heat sink 38. The heat conduction plate 37 is made of a material with excellent thermal conductivity, for example, a metal material containing aluminum or copper as its main component.

[0030] A heat sink 38 is provided below the thermal conduction plate 37 as a heat radiator. The heat sink 38 has, for example, a flat fin shape. The shape of the heat sink 38 may be any shape that can promote heat dissipation from the temperature adjustment mechanism 36 and has a large surface area. The heat sink 38 is made of a material with excellent thermal conductivity, for example, a metal material whose main component is aluminum or copper.

[0031] The heat sink 38 may be provided with a fan capable of blowing cooling air to further promote heat dissipation. Furthermore, the directionality of the air from the fan may be improved by placing a duct between the fan and the heat sink 38. The duct allows the air from the fan to pass efficiently over the surface of the heat sink 38.

[0032] The configuration (system) of the sample processing device 100 will be described in more detail below with reference to FIG.

[0033] The sample processing device 100 includes a control unit 110. As shown in Figure 4, the control unit 110 is electrically connected to and controls the transport unit 20, disk 31, temperature adjustment mechanism 36 of each stage 32, temperature sensor 40, humidity sensor 41, memory unit 50, and operation unit 51. The control unit 110 can also be considered a computer system including various semiconductor devices such as a CPU.

[0034] The control unit 110 controls each transport operation performed by the transport unit 20. Examples of transport operations controlled by the control unit 110 include an operation of gripping or releasing the slide glass 1 by the gripper 21, an operation of transporting the slide glass 1 from the supply unit 10 to the staining unit 30 by the transport unit 20, and an operation of transporting the slide glass 1 from the staining unit 30 to the storage unit 11 by the transport unit 20.

[0035] The control unit 110 also controls each operation performed by the disk 31. For example, the control unit 110 controls the rotation operation of the disk 31. Note that the control unit 110 also controls a nozzle (not shown) for supplying a chemical solution to the slide glass 1.

[0036] Furthermore, the control unit 110 controls the temperature of each stage 32. That is, the control unit 110 controls the temperature adjustment mechanism 36 provided on each stage 32 to adjust the temperature of the stage 32 to a desired temperature. In other words, the portion of the configuration of the sample processing device 100 that includes the temperature adjustment mechanism 36 and the control unit 110 that controls the temperature adjustment mechanism 36 functions as the temperature adjustment device 200.

[0037] More specifically, the temperature adjustment mechanism 36 includes a Peltier element 361 and an element temperature sensor 362 that detects the temperature of the Peltier element 361. A power supply circuit 39 for supplying power to the Peltier element 361 is connected to the Peltier element 361. The element temperature sensor 362 measures the temperature of the Peltier element 361 and inputs the measured temperature to the control unit 110. The control unit 110 controls the power supply circuit 39 in accordance with a set temperature adjustment protocol so that the temperature of the Peltier element 361 becomes a target temperature.

[0038] In this embodiment, the control unit 110 performs PID control based on the difference between the temperature acquired by the element temperature sensor 362 and the target temperature. The manipulated variable for PID control is the DC voltage value applied to the Peltier element 361. The power supply circuit 39 applies the DC voltage value determined by the control unit 110 to the Peltier element 361. Note that each temperature adjustment mechanism 36 can be operated with an independent temperature control protocol depending on the type of sample processing.

[0039] Furthermore, as will be described in more detail later, when the staining process is performed by the sample processing device 100, that is, when the temperature of the slide glass 1 is adjusted by the temperature adjustment mechanism 36, the temperature adjustment device 200 detects abnormalities in the equipment (hereinafter also referred to as equipment abnormalities) including the Peltier element 361 and element temperature sensor 362 provided in the temperature adjustment mechanism 36.

[0040] The environmental temperature detected by the temperature sensor 40 and the environmental humidity detected by the humidity sensor 41 are transmitted to the control unit 110. The control unit 110 controls the temperature of each stage 32 using the temperature adjustment mechanism 36, taking into account the environmental temperature and humidity detected by the temperature sensor 40 and the humidity sensor 41.

[0041] The storage unit 50 stores various data used in the sample processing device 100, such as protocols used in staining processes and detailed data for each slide glass 1. Each piece of data can be rewritten, erased, or read out as needed by the control unit 110. The storage unit 50 is configured to include, for example, a flash memory or a hard disk.

[0042] The operation unit 51 is a device that allows an operator to give commands to the control unit 110. The operation unit 51 includes an input device that allows the operator to input instructions and the like, and a display device that is configured with a monitor or the like. The input device is, for example, a keyboard or a mouse. The operation unit 51 may also be a touch panel or the like that has the functions of an input device and a display device.

[0043] Here, an example of a staining process performed using the sample processing device 100 will be briefly described.

[0044] In the supply unit 10, the slide glass 1 with the sample placed thereon is placed on the tray 12. The slide glass 1 is gripped by the grip portion 21 of the transport unit 20, and is carried from the supply unit 10 to the staining unit 30 by the transport unit 20, where it is placed on the stage 32 on the disk 31.

[0045] The stage 32 and the slide glass 1 move between the nozzles arranged around the disk 31 as the disk 31 rotates. The slide glass 1 is subjected to a staining process according to a preset protocol. The protocol specifies the temperature, time, and chemical solution to be supplied required for each process, such as deparaffinization, antigen activation, and staining.

[0046] When the staining process is completed, the slide glass 1 on the stage 32 is transported from the staining unit 30 to the storage unit 11 by the transport unit 20 and placed on the tray 13. The slide glass 1 collected on the tray 13 is removed by the operator at an appropriate time.

[0047] <Temperature Control Device> The temperature control device (temperature adjustment device) 200 installed in the sample processing device 100 will be described in detail below with reference to FIG. 5 and subsequent figures.

[0048] Fig. 5 is a block diagram showing the configuration of a temperature control device according to an embodiment. Fig. 6 is a diagram showing an example of a resistance-temperature characteristic table of a Peltier element. Fig. 7 is a flowchart illustrating an example of a method for detecting an equipment abnormality by a temperature control device according to an embodiment.

[0049] 5, the temperature adjustment device 200 includes a temperature adjustment mechanism 36 provided for each slide glass 1, which is a temperature adjustment target (object), a power supply circuit 39, and a control unit 110. The temperature adjustment mechanism 36 includes a Peltier element 361 and an element temperature sensor 362 provided on each stage 32 as described above.

[0050] The temperature control device 200 may include a heat spreader (heat transfer block) 34 in addition to the above-described components such as the temperature adjustment mechanism 36. However, the heat spreader 34 is a component for uniformly transferring heat from the Peltier element 361 to the slide glass 1, which is the temperature control target, and is not an essential component of the temperature control device 200.

[0051] The power supply circuit 39 has a Peltier element driver 391, an AC signal generator 392, a low-pass filter 393, and a high-pass filter 394. The Peltier element driver 391 applies a DC voltage to the Peltier element 361 to heat or cool the Peltier element 361. The AC signal generator 392 superimposes an AC voltage on the DC voltage output by the Peltier element driver 391 and applies the superimposed voltage to the Peltier element 361. The amplitude and frequency of this AC voltage are set within ranges that do not affect the temperature control of the Peltier element 361.

[0052] The low-pass filter 393 is provided to pass only the DC voltage output from the Peltier element driver 391 and not pass the AC voltage output from the AC signal generator 392. On the other hand, the high-pass filter 394 is provided to pass only the AC voltage output from the AC signal generator 392 and not pass the DC voltage output from the Peltier element driver 391.

[0053] In the temperature adjustment device 200 of this embodiment, when the temperature of the slide glass 1 is adjusted by the temperature adjustment mechanism 36 as described above, an abnormality in the temperature adjustment mechanism 36 is detected. As an example, the control unit 110, which also functions as the temperature adjustment device 200, has an abnormality detection unit 120, which detects an abnormality in the temperature adjustment mechanism 36.

[0054] The device abnormality detection unit 120 includes a temperature acquisition unit 121 , a current / voltage waveform acquisition unit 122 , a resistance value calculation unit 123 , a memory unit 124 , a resistance value conversion unit 125 , a comparison unit 126 , and an abnormality determination unit 127 .

[0055] The temperature acquisition unit 121 converts the output of the element temperature sensor 362 into a temperature. The current / voltage waveform acquisition unit 122 acquires the AC voltage waveform across both ends of the Peltier element 361 and the AC current waveform flowing through the Peltier element 361.

[0056] The resistance value calculation unit 123 periodically acquires the resistance value of the Peltier element 361 while superimposing an AC current on a DC current for driving the Peltier element 361. More specifically, the resistance value calculation unit 123 periodically calculates the actual resistance value of the Peltier element 361 based on the results acquired by the current / voltage waveform acquisition unit 122. As an example, the resistance value calculation unit 123 calculates the resistance value by dividing the effective values ​​of the current and voltage waveforms acquired by the current / voltage waveform acquisition unit 122. At this time, the resistance value calculation unit 123 may perform moving average processing or add and average multiple waveforms extracted for the purpose of denoising, i.e., removing noise.

[0057] The memory unit 124 stores a resistance-temperature characteristic table of the Peltier element 361. Here, for example, when staining a slide glass 1, multiple target temperatures are set. That is, in one staining process, the temperature of the slide glass 1 is sequentially adjusted to multiple target temperatures. In other words, in one staining process, a temperature control cycle in which multiple target temperatures are set is executed. The resistance characteristic table records the initial resistance value (value at the time of shipment of the device) and the actual resistance value of the Peltier element 361 each time the staining process is performed repeatedly over a long period of time.

[0058] The resistance-temperature characteristic table shown in Figure 6 is an example in which five target temperatures Ta to Te are set for a single dyeing process, and the actual resistance values ​​of the Peltier element 361 corresponding to each target temperature Ta to Te are all recorded, from the initial value to the previous value. When the next dyeing process is performed, the resistance value of the Peltier element 361 at that time is acquired as the current value, and the previous value in the resistance-temperature characteristic table is updated to the current value. In this example, the resistance value of the Peltier element 361 is recorded for each of the multiple target temperatures Ta to Te in the resistance-temperature characteristic table, but it may also be recorded for just one of the target temperatures Ta to Te.

[0059] The resistance value conversion unit 125 obtains the resistance value of the Peltier element 361 at the obtained temperature Tx from the obtained temperature Tx obtained by the temperature acquisition unit 121. More specifically, the resistance value conversion unit 125 obtains the resistance value of the Peltier element 361 at the obtained temperature Tx. Specifically, the resistance value conversion unit 125 obtains the initial value and the previous value of the resistance value of the Peltier element 361 from the obtained temperature Tx by referring to the resistance-temperature characteristic table stored in the storage unit 124.

[0060] As an example, when the acquired temperature Tx acquired by the temperature acquisition unit 121 is the target temperature Tb, the resistance value conversion unit 125 acquires the initial value Rb(0) and the previous value Rb(n-1) of the resistance value of the Peltier element 361 at the target temperature Tb by referring to the resistance-temperature characteristics table shown in Fig. 6. Of course, the resistance value conversion unit 125 may also determine the initial value and the previous value of the resistance value of the Peltier element 361 when the acquired temperature Tx is one of the target temperatures Ta, Tc to Te.

[0061] The comparison unit 126 compares the resistance value of the Peltier element 361 (hereinafter also referred to as the converted resistance value) calculated by the resistance value conversion unit 125 from the acquired temperature Tx with the actual resistance value of the Peltier element 361 (hereinafter also referred to as the actual resistance value) calculated by the resistance value calculation unit 123. That is, the comparison unit 126 compares the first resistance value calculated this time by the resistance value calculation unit 123 with the second resistance value calculated previously. Note that this comparison by the comparison unit 126 will be described in detail later.

[0062] The abnormality determination unit 127 determines an equipment abnormality in the temperature adjustment mechanism 36 based on the comparison result by the comparison unit 126. In this example, the abnormality determination unit 127 determines, as the equipment abnormality, whether or not there is an abnormality in the Peltier element 361 and the element temperature sensor 362 that constitute the temperature adjustment mechanism 36. More specifically, the abnormality determination unit 127 determines whether or not there is a malfunction or the like in the Peltier element 361 and the element temperature sensor 362, and also determines whether or not the Peltier element 361 has reached the end of its life.

[0063] If the abnormality determination unit 127 determines that there is an abnormality in the element temperature sensor 362, the sample processing apparatus 100 equipped with the temperature adjustment device 200 preferably stops the staining process. The sample processing apparatus 100 preferably stops the transport of the slide glass 1 by the transport unit 20 for at least the stage 32 corresponding to the temperature adjustment mechanism 36 including the element temperature sensor 362 for which an abnormality has been detected. Furthermore, if the abnormality determination unit 127 determines that the Peltier element 361 has reached the end of its life, the sample processing apparatus 100 or the temperature adjustment device 200 preferably notifies the operator of this fact.

[0064] 7 is a flowchart illustrating a procedure for detecting an abnormality in the Peltier element and the element temperature sensor in a temperature adjustment device according to an embodiment. Hereinafter, an example of a procedure for detecting an abnormality in the temperature adjustment mechanism 36 in the temperature adjustment device 200 will be described with reference to FIG. 7 .

[0065] As a preliminary process for detecting equipment abnormalities, the resistance value of the Peltier element 361 at each target temperature (for example, target temperatures Ta to Te in FIG. 6) is measured at the time of shipment or installation of the sample processing device 100 in which the temperature adjustment device 200 is mounted, and the measured values ​​are stored as initial values ​​Ra(0) to Re(0) in the memory unit 124. At this point, the initial values ​​Ra(0) to Re(0) also correspond to the previous values. This preliminary process is performed under the assumption that there are no abnormalities in the element temperature sensor 362 and the Peltier element 361.

[0066] 7, when detecting an equipment abnormality, first, in step S01, the output of the element temperature sensor 362 is acquired, and it is determined whether or not there is an abnormality in the acquired output of the element temperature sensor 362 (step S02). An output abnormality here refers to an obvious abnormality, such as when the output of the element temperature sensor 362 is stuck at L level (low level) or H level (high level) due to a disconnection or short circuit, or when an unexpected temperature (for example, a temperature above a preset upper threshold or below a preset lower threshold) is acquired, and can be easily determined from the acquisition result of the temperature acquisition unit 121. In this example, the determination in step S02 is made by the temperature acquisition unit 121.

[0067] If it is determined that there is an output abnormality in the element temperature sensor 362 (step S02: Yes), the process proceeds to step S03. In step S03, the element temperature sensor 362 is detected as having a malfunction, and the abnormality detection process is then terminated. The sample processing device 100 also stops operation as appropriate based on this detection result. As an example, the sample processing device 100 stops operation of the temperature adjustment mechanism 36 that includes the element temperature sensor 362 for which an abnormality has been detected. The sample processing device 100 also controls the transport unit 20 based on the detection result to stop transport of the slide glass 1 to the stage 32 on which the element temperature sensor 362 for which an abnormality has been detected is installed.

[0068] On the other hand, if it is determined that the output of the element temperature sensor 362 is normal, that is, if it is determined that the output of the element temperature sensor 362 is not abnormal (step S02: No), proceed to step S04, and, for example, start a normal temperature control cycle for the dyeing process and appropriately control each Peltier element 361 to reach the target temperature Ta to Te, while continuing to detect equipment abnormalities.

[0069] Next, the presence or absence of an abnormality in the Peltier element 361 is determined based on the temperature (acquired temperature Tx) of the Peltier element 361 obtained from the output of the element temperature sensor 362. As an example, in step S05, it is determined whether the acquired temperature Tx acquired by the temperature acquisition unit 121 has reached a target temperature (for example, the target temperature Tb in FIG. 6 ) within a preset time period. That is, in step S05, it is determined whether the temperature of the Peltier element 361 has reached the target temperature Tb within a certain fixed time period.

[0070] If the temperature of the Peltier element 361 (acquired temperature Tx) does not reach the target temperature Tb within the set time (step S05: No), the process proceeds to step S06, where a failure of the Peltier element 361 is detected and the abnormality detection process ends. On the other hand, if the temperature of the Peltier element 361 reaches the target temperature Tb within the set time (step S05: Yes), the AC signal generator 392 is activated to superimpose an AC current on the DC current used to drive the Peltier element 361. Then, the current / voltage waveform acquisition unit 122 and the resistance value calculation unit 123 calculate a current value Rb(n), which is the actual resistance value (first resistance value) of the Peltier element 361 at the target temperature Tb (step S07).

[0071] Next, in step S08, the comparison unit 126 compares this current value Rb(n) with the previous value Rb(n-1) of the resistance of the Peltier element 361, which is calculated from the obtained temperature Tx by the resistance value conversion unit 125 as described above, and checks the degree of agreement between the current value Rb(n) and the previous value Rb(n-1). As an example, it determines whether the difference Rv1 between the current value Rb(n) and the previous value Rb(n-1) is equal to or less than a predetermined first threshold value Rth1, and if the difference is equal to or less than the first threshold value Rth1, it determines that the current value Rb(n) and the previous value R22 agree.

[0072] If it is determined that Rth1<Rv1 and the current value Rb(n) does not match the previous value Ra(n-1) (step S08: No), the process proceeds to step S09, where a failure of the element temperature sensor 362 is detected, and the process ends. In step S09, for example, a failure or peeling of the element temperature sensor 362, or a temporary defect of the element temperature sensor 362 due to the adhesion of condensation, can be detected.

[0073] Furthermore, since it is determined in step S05 that the Peltier element 361 is normal as described above, it is possible to detect in step S09 that the failure is not in the Peltier element 361 but in the element temperature sensor 362.

[0074] 8A is a diagram showing a typical change over time in the resistance value (resistance value at target temperature Tb) of the Peltier element in a normal state. Note that the normal state here refers to a state in which there is no abnormality in the Peltier element 361 and the element temperature sensor 362.

[0075] It is generally known that Peltier elements deteriorate with repeated temperature control cycles. Therefore, for example, as shown in Figure 8A, the resistance value of the Peltier element gradually increases with repeated temperature control cycles. However, the change in the resistance value of the Peltier element during a single temperature control cycle in a sample processing device is negligible.

[0076] Therefore, in the temperature adjustment device 200, when the Peltier element 361 and the element temperature sensor 362 are normal, the current value Rb(n) and the previous value Rb(n-1) at the target temperature Tb generally match.

[0077] On the other hand, if the error in the output of the element temperature sensor 362 increases due to, for example, a malfunction of the element temperature sensor 362, peeling, or the adhesion of condensation, the acquired temperature Tx acquired by the temperature acquisition unit 121 may be lower than the actual temperature of the Peltier element 361. For example, when the acquired temperature Tx acquired by the temperature acquisition unit 121 is T1°C, the actual temperature of the Peltier element 361 may be T1+α°C. For example, while the resistance value of the Peltier element 361 at the target temperature Tb°C may be intended to be measured, the resistance value of the Peltier element 361 at the target temperature Tb+α°C may actually be measured.

[0078] 8B is a diagram showing a typical change over time in the resistance value (resistance value at the target temperature Tb) of the Peltier element when an abnormality occurs. Note that the abnormality here refers to a state in which there is no abnormality in the Peltier element, but an abnormality has occurred in the element temperature sensor.

[0079] 8B, when the Peltier element 361 is normal but an abnormality occurs in the element temperature sensor 362, the difference Rv1 between the current value Rb(n) and the previous value Rb(n-1) at the target temperature Tb becomes larger than when the Peltier element 361 is normal. In other words, the current value Rb(n) measured at the target temperature Tb+α°C becomes larger than the previous value Rb(n-1) measured at the target temperature Tb before the failure of the element temperature sensor 362.

[0080] Therefore, when the Peltier element 361 is in a normal state, by comparing the current resistance value Rb(n) of the Peltier element 361 with the previous resistance value Rb(n-1), it is possible to properly detect an abnormality in the element temperature sensor 362. In practice, it is preferable to determine whether the current resistance value and the previous resistance value match by providing an appropriate margin, taking into account the measurement accuracy of the resistance value and temperature of the Peltier element 361.

[0081] Furthermore, in this example, if an abnormality is detected in the element temperature sensor 362 or the Peltier element 361, the sample processing device 100 is stopped. As an example, the transport unit 20 stops transporting the slide glass 1 to the stage 32 corresponding to the element temperature sensor 362 or Peltier element 361 for which an abnormality has been detected. This makes it possible to prevent an abnormal temperature control cycle from being performed on the slide glass 1.

[0082] Furthermore, if it is determined in step S08 that the current value Rb(n) and the previous value Rb(n) match (step S08: Yes), the comparison unit 126 then checks the difference between the current value Rb(n) at the target temperature Tb and the initial value Rb(0) of the Peltier element 361 at the target temperature Tb referenced by the resistance value conversion unit 125 (step S010). That is, in step S010, it is determined whether the difference Rv2 between the initial value Rb(0) and the current value Rb(n) of the Peltier element 361 is abnormal. As an example, in step S010, it is determined whether the difference Rv2 between the initial value Rb(0) and the current value Rb(n) is equal to or greater than a predetermined second threshold value Rth2.

[0083] If the difference Rv2 between the initial value Rb(0) and the current value Rb(n) is equal to or greater than the second threshold value Rth2 and is determined to be abnormal (step S10: Yes), the process proceeds to step S011, where the difference Rv2 is detected as the end of the life of the Peltier element 361. When the end of the life of the Peltier element 361 is detected, for example, the detected information is notified to the operator, and then the abnormality determination process ends. This abnormality determination process makes it possible to detect the end of the life of the Peltier element 361 early during the normal temperature control cycle of the dyeing process.

[0084] 9 is a diagram showing a typical change over time in the resistance value (resistance value at the target temperature Tb) of the Peltier element when an abnormality occurs. Note that an abnormality here refers to a state in which the Peltier element or element temperature sensor is not broken, but the Peltier element has reached the end of its life.

[0085] Generally, Peltier elements deteriorate with repeated temperature control cycles and eventually reach the end of their lifespan. Furthermore, the lifespan of a Peltier element varies depending on the usage environment and operating conditions. For example, as shown in FIG. 9 , the resistance value of a Peltier element gradually increases with repeated temperature control cycles. Even if the Peltier element and the element temperature sensor are normal, the difference between the initial value and the current value at each target temperature gradually increases. In the temperature control device 200, for example, the difference Rv2 between the initial value Rb(0) and the current value Rb(n) at the target temperature Tb gradually increases.

[0086] Therefore, in this example, the resistance value of the Peltier element 361 is measured for each temperature control cycle (for example, a cycle between target temperatures Ta and Te), and when the difference between the current measured value and the initial value exceeds a preset second threshold value (for example, initial value + 10%), the end of the life of the Peltier element 361 is detected. For example, when the difference Rv2 between the initial value Rb(0) and the current value Rb(n) at the target temperature Tb exceeds the second threshold value Rth2, the end of the life of the Peltier element 361 is determined.

[0087] Furthermore, when the end of the life of the Peltier element 361 is detected, it is preferable to notify the operator or the like. This can prevent the sample processing device 100 from shutting down due to an unexpected temperature control abnormality while it is in operation. Furthermore, the resistance value of the Peltier element 361 measured by this method is less dependent on the ambient temperature. Therefore, the temperature control device 200 of this embodiment can appropriately measure the resistance value of the Peltier element 361 even during a temperature control cycle.

[0088] On the other hand, if it is determined that the difference Rv2 between the current value Rb(n) and the initial value Rb(0) is less than the second threshold value Rth2 and that the difference Rv2 is normal (step S010: No), that is, if it is determined that there is no abnormality in the Peltier element 361 or the element temperature sensor 362, then in step S012, the previous value Rb(n-1) in the resistance value temperature table is updated to the current value Rb(n).Then, the process returns to step S02, and the temperature control and abnormality determination process according to the set temperature control protocol is continued.

[0089] In the above-described embodiment, the resistance value of the Peltier element 361 is obtained at temperatures corresponding to the target temperatures Ta to Te of the temperature adjustment cycle. Therefore, at target temperatures that are set less frequently and updated less frequently, the resistance value of the Peltier element 361 is updated less frequently. Therefore, the resistance value of the Peltier element 361 may increase due to repeated temperature adjustment cycles between the acquisition of the previous value and the acquisition of the current value. In this case, the previous and current resistance values ​​may be determined to be inconsistent, which could result in an erroneous detection of a malfunction of the element temperature sensor 362.

[0090] Therefore, the temperature adjustment device 200 may be configured to detect equipment abnormalities at times other than during the normal operation of the sample processing device 100, such as during a staining process. For example, the Peltier element 361 may be controlled to a predetermined target temperature during initialization or periodically to detect the above-mentioned equipment abnormalities. This forcibly updates the resistance value of the Peltier element 361 at each target temperature stored in the memory unit 124. This makes it possible to prevent erroneous detection of a malfunction of the element temperature sensor 362 as described above.

[0091] For example, instead of a resistance-temperature characteristic table, a resistance-temperature characteristic equation of a first or second order may be stored, and the resistance value (converted resistance value) of the Peltier element 361 may be calculated each time from the detection result of the element temperature sensor 362. For example, if there are a large number of target temperatures at which the resistance value of the Peltier element 361 is measured for anomaly detection, or if anomaly detection is desired at any controlled temperature, storing a resistance-temperature characteristic table would require a large-capacity memory unit 124. However, by calculating the resistance value using the resistance-temperature characteristic equation, it is possible to save memory capacity equivalent to the memory unit 124.

[0092] Furthermore, when calculating the resistance of the Peltier element 361 using the resistance-temperature characteristic equation, it is also possible to detect abnormalities in the element temperature sensor 362, etc., by acquiring the resistance of the Peltier element 361 at regular intervals or at any timing, regardless of the temperature control temperature (target temperature) in the temperature control cycle. Note that due to the response speed of the element temperature sensor 362 to the temperature of the Peltier element 361, the relationship between the actual temperature of the Peltier element 361 and the temperature acquired by the element temperature sensor 362 may affect the temperature during temperature control. Therefore, this effect must be taken into consideration when using the resistance-temperature characteristic equation.

[0093] As described above, the temperature adjustment device 200 of the present disclosure periodically acquires the resistance value of the Peltier element while superimposing an AC current on the DC current for driving the Peltier element 361, and detects an equipment abnormality based on the first resistance value acquired currently (e.g., the current value) and the second resistance value acquired previously (e.g., the previous value). Furthermore, the temperature adjustment device 200 detects the lifespan of the Peltier element 361 based on the first resistance value, which is the current value, and an initial value acquired when the device was first shipped. This makes it possible to provide a temperature adjustment device that can appropriately detect equipment abnormalities such as abnormalities in the Peltier element 361 and the element temperature sensor 362, or the lifespan of the Peltier element 361.

[0094] In the above-described embodiment, the previous value is used as the second resistance value obtained before the current one, but the second resistance value does not necessarily have to be the previous value. The second resistance value may be any value that is substantially the same as the current value when the Peltier element 361 is in a normal state, and may be, for example, a value obtained in a temperature control cycle several times before the current one. Similarly, the initial value does not necessarily have to be the value first obtained at the time of shipment, but may be a value obtained at the time the device is first shipped. The initial value may be, for example, a value obtained when several temperature control cycles have been performed after shipment.

[0095] Although the embodiments of the present disclosure have been described above, the technology of the present disclosure is not limited to the above-described embodiments and includes various modifications. For example, the technology of the present disclosure can also be applied to a temperature control system that does not have a temperature control cycle and always controls the temperature to a constant value, and is not necessarily limited to a system that includes all of the configurations described above. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace part of the configuration of each embodiment with other configurations.

[0096] 1: slide glass, 10: supply unit, 11: storage unit, 12, 13: tray, 20: transport unit, 21: grip section, 30: staining unit, 31: disk, 32: stage (holder), 34: heat spreader (heat transfer block), 35: fixing base, 36: temperature adjustment mechanism, 37: heat conduction plate, 38: heat sink, 39: power supply circuit, 40: temperature sensor, 41: humidity sensor, 50: memory section, 51: operation section, 100: sample Processing device, 110: control unit, 120: equipment abnormality detection unit, 121: temperature acquisition unit, 122: current / voltage waveform acquisition unit, 123: resistance value calculation unit, 124: storage unit, 125: resistance value conversion unit, 126: comparison unit, 127: abnormality determination unit, 200: temperature control device (temperature control system), 361: Peltier element, 362: element temperature sensor, 391: Peltier element driver, 392: AC signal generator, 393: low-pass filter, 394: high-pass filter

Claims

1. A temperature control device comprising: a temperature adjustment mechanism having a Peltier element and an element temperature sensor that detects the temperature of the Peltier element and that can change the temperature of an object; and a control unit that controls the temperature adjustment mechanism, wherein the control unit comprises: a resistance value calculation unit that periodically obtains the resistance value of the Peltier element in a state in which an AC current is superimposed on a DC current for driving the Peltier element; and an abnormality determination unit that determines whether or not there is an equipment abnormality based on a first resistance value currently obtained by the resistance value calculation unit and a second resistance value obtained previously.

2. A temperature control device according to claim 1, wherein the abnormality determination unit determines whether or not the device abnormality is the abnormality of the element temperature sensor.

3. A temperature control device according to claim 2, wherein the abnormality determination unit determines that an abnormality has occurred in the device when the difference between the first resistance value and the second resistance value is greater than a preset first threshold value.

4. A temperature control device according to claim 1, wherein the abnormality determination unit determines whether or not there is an abnormality in the Peltier element based on the temperature of the Peltier element that is reached within a preset time period when the Peltier element is driven.

5. A temperature control device according to claim 1, wherein the second resistance value is an initial resistance value of the Peltier element obtained when the device is first shipped, and the abnormality determination unit determines whether the Peltier element has reached the end of its life, as the equipment abnormality, based on the first resistance value and the initial value.

6. A temperature control device according to claim 5, wherein the abnormality determination unit determines that the Peltier element has reached the end of its life when the difference between the first resistance value and the initial value is greater than a preset second threshold value.

7. A sample processing apparatus comprising: a plurality of stages on which slide glasses are respectively placed; a staining unit for staining samples on the slide glasses; and a temperature control unit capable of individually changing the temperature of the slide glasses, wherein the temperature control unit comprises: a temperature adjustment mechanism having a Peltier element provided on each of the stages and an element temperature sensor for detecting the temperature of the Peltier element; and a control unit for controlling the temperature adjustment mechanism, wherein the control unit comprises: a resistance value calculation unit that periodically obtains the resistance value of the Peltier element while an AC current is superimposed on a DC current for driving the Peltier element; and an abnormality determination unit that determines an equipment abnormality based on a first resistance value currently obtained by the resistance value calculation unit and a second resistance value obtained previously.

8. A sample processing apparatus according to claim 7, further comprising a transport unit for transporting the slide glass, wherein the abnormality determination unit determines whether or not there is an abnormality in the element temperature sensor as the equipment abnormality, and when the abnormality determination unit determines that there is an abnormality in the element temperature sensor, the transport unit stops transporting the slide glass to the stage corresponding to the element temperature sensor determined to be abnormal.

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