JP6448259B2 - Thermostatic bath device - Google Patents

Description

  The present invention relates to a thermostatic chamber device that is preferably implemented in, for example, a low-temperature thermostatic chamber device.

  As a conventional example of this type of low-temperature thermostatic chamber device, an external refrigerator or the like as a cooling device is provided, a temperature sensor is provided in the thermostatic chamber, and the refrigerator is driven and controlled according to the detection result of the temperature sensor. In general, the inside of the low-temperature thermostatic chamber is configured to be maintained at a set temperature (see Patent Document 1 below).

JP-A-6-277530

  However, in the conventional thermostat apparatus as described above, the efficiency of maintaining the set temperature is not yet sufficient, and a thermostat capable of achieving more efficient set temperature maintenance has been desired.

  The present invention has been conceived in view of the above problems, and an object of the present invention is to provide a thermostatic chamber device that can achieve more efficient set temperature maintenance.

The invention of claim 1, wherein in order to achieve the above object, has a constant temperature bath, a constant temperature bath apparatus for cooling a set temperature by the refrigerant to reservoir fluid stored in該恒warm bath, a constant temperature the reservoir fluid A circulation pipe that is drawn out to the outside of the tank and returned to the constant temperature tank, circulation drive means that is connected to the circulation pipe and drives the stored fluid to circulate, and a supply for supplying a refrigerant that cools the stored fluid into the constant temperature tank A heat exchanger in which heat is exchanged between a pipe, a discharge pipe that discharges the refrigerant that cools the stored fluid to the outside of the thermostatic chamber, a stored fluid that passes through the circulation pipe, and a refrigerant that passes through the discharge pipe , wherein the at least one or more blowing nozzles are provided in a thermostat, the blowout nozzle is characterized by being configured to out can blow the gas toward the reservoir fluid in the thermostatic chamber.

Here, the “constant temperature tank” corresponds to the cooling tank 3 in the embodiment, the “reserved fluid” corresponds to the antifreeze liquid 2 in the embodiment, the “refrigerant” corresponds to the liquid nitrogen in the embodiment, and the “constant temperature” The “tank device” corresponds to the actual temperature test device 1 of the cast steel butterfly valve in the embodiment.
According to the above arrangement, the gas is issued can blown toward the blowout nozzle reservoir fluid in the thermostatic chamber, the reservoir fluid is to be 撹拌. As a result, the temperature of the stored fluid is made uniform, so that the entire stored fluid is maintained at a temperature closer to the constant temperature.
In addition to being cooled by the refrigerant in the thermostatic chamber, the stored fluid is cooled by exchanging heat with the refrigerant in an external heat exchanger, and an extremely efficient cooling process is performed.

Further, the invention according to claim 2 is the thermostatic chamber device according to claim 1, wherein the discharge pipe is connected to the blowing nozzle, and the refrigerant passing through the discharge pipe is stored in the heat exchanger and heat. It is configured to be exchanged so that at least a part thereof is gasified and blown out from the blowing nozzle .

According to the said structure, the gas which blows off from a blowing nozzle is gasified because a refrigerant | coolant is heat-exchanged with the stored fluid with a heat exchanger. As described above, the refrigerant is reused, and it is not necessary to separately prepare the gas blown from the blowing nozzle, and the cost can be reduced .

According to the present invention, the gas is issued can blown toward the blowout nozzle reservoir fluid in the thermostatic chamber, the reservoir fluid is to be 撹拌. As a result, the temperature of the stored fluid is made uniform, so that the entire stored fluid is maintained at a temperature closer to the constant temperature.

The block diagram of the actual temperature test apparatus of the cast steel butterfly valve which concerns on embodiment. The top view of the cooling tank with which the actual temperature test apparatus shown in FIG. 1 is equipped. The enlarged view of a cooling tank side wall. The block diagram which shows the electrical structure of a real temperature test apparatus. The flowchart which shows the cooling process operation | movement in a real temperature test apparatus. The flowchart which shows the cooling process operation | movement in a real temperature test apparatus. The flowchart which shows the cooling process operation | movement in a real temperature test apparatus.

Hereinafter, the present invention will be described in detail based on embodiments. In the following embodiments, an actual temperature test device for a cast steel butterfly valve will be described as an example of a thermostatic chamber device according to the present invention.
FIG. 1 is a configuration diagram of an actual temperature test apparatus for a cast steel butterfly valve according to an embodiment, and FIG. 2 is a plan view of a cooling tank provided in the actual temperature test apparatus for a cast steel butterfly valve. Here, in the following embodiments, an actual temperature test device for a cast steel butterfly valve for LPG will be described as an example of an actual temperature test device for a low temperature valve. The actual temperature test of the LPG butterfly valve is to cool the butterfly valve to around -46 ° C where the LPG cast steel butterfly valve is actually used. In this cooled state, the sealing performance of the cast steel butterfly valve A test that is performed to confirm the quality of a product.

  A butterfly valve actual temperature test apparatus (hereinafter abbreviated as an actual temperature test apparatus) 1 includes a cooling tank 3 that stores an antifreeze liquid 2 that functions as a refrigerant, and an antifreeze liquid 2 in a state where the butterfly valve 4 is immersed in the antifreeze liquid 2. Cooling means 5 for cooling. In the cooling tank 3, the butterfly valve 4 is fixed by a pair of surface plates (not shown) which are fixing tools.

  Here, the antifreeze solution used is a commercially available antifreeze solution, and it is possible to use an antifreeze solution that contains glycerin and ethanol as main components and does not freeze up to −55 ° C., for example. As a specific example of the antifreeze, a trade name: Frozen (Koo) Run Blue (manufactured by Furukawa Pharmaceutical Co., Ltd.) can be exemplified. The antifreeze liquid preferably contains a rust inhibitor. Cast steel butterfly valves are prone to rust, and rusting may occur if an extremely long-term actual temperature test is performed. However, the problem of rusting is solved with an antifreeze containing a rust inhibitor.

  The cooling means 5 includes a storage tank 6 that stores liquid nitrogen, an electromagnetic on-off valve 7 that supplies and stops liquid nitrogen from the storage tank 6, a circulation pump 8, a heat exchanger 9, and a liquid nitrogen piping system. And an antifreeze piping system. The liquid nitrogen piping system is connected to the piping L1 that is drawn out from the lower portion of the storage tank 6 and provided with the electromagnetic on-off valve 7 and the butterfly valve 4 in the cooling tank 3 connected to the piping L1 so as not to contact the cooling tank 3. A pipe L2 fixed to the bottom surface and the side surface and drawn out of the cooling tank 3, a pipe L3 connected to the pipe L2 and passing through the heat exchanger 9, and a pipe L3 connected to the pipe L3 and led to the blowing nozzle 11 via the manual valve 10. The pipe L4 is connected to the pipe L3, and the pipe L5 is connected to the pipe L3 and guided to the nozzle through the manual valve 12. Here, at least the pipe L2 among the pipes L1 to L5 functions as a cooling pipe for cooling the antifreeze liquid, and specifically, is constituted by a stainless steel flexible tube.

  Further, as shown in FIG. 2, the blowing nozzles 11 and 11 are respectively arranged at diagonal positions in the cooling tank 3 and function to blow out nitrogen gas into the cooling tank 3. By providing such two blowing nozzles 11 and 11 at diagonal positions, the antifreezing liquid can be rotated and efficiently stirred by blowing nitrogen gas, and the liquid temperature can be made uniform. In addition, since it is sufficient if the blowout nozzle can stir the antifreeze liquid, the number of blowout nozzles is not limited to two, and may be one, or may be three or more.

Moreover, as shown in FIG. 3, you may comprise so that several (for example, three) blowing nozzle 11a, 11b, 11c may be arrange | positioned at each diagonal position at intervals up and down. In this case, the diameters of the blowing nozzles 11a, 11b, and 11c may all be the same, and the diameter is different in the vertical direction. For example, the blowing nozzle 11a at the upper position is the largest, and the blowing nozzle at the lower position. You may make it the structure which 11c sets to the smallest.
The blowing nozzles 11 and 11 and the blowing nozzles 11a, 11b, and 11c may be configured to be embedded in the side wall of the cooling tank 3, and a branched pipe (a branched portion corresponds to the blowing nozzle) is provided in the cooling tank 3. The structure which is sunk in and fixed.

  The piping system of the antifreeze liquid 2 includes a pipe M1 that pumps up the antifreeze liquid 2 in the cooling tank 3, a pipe M2 that is connected to the pipe M1 and supplies the antifreeze liquid 2 to the circulation pump 8 via the manual valve 15, and a circulation pump 8 A pipe M3 as a return pipe that supplies the antifreeze liquid 2 to the heat exchanger 9 by driving and leads to the cooling tank 3; a pipe M4 that is connected to the pipe M3 and supplies the antifreeze liquid into the cooling tank 3; and supplied from the heat exchanger 9 A pipe M5 for extracting the antifreeze liquid into an antifreeze liquid storage tank (not shown) and a pipe M6 for sucking the antifreeze liquid from the antifreeze liquid storage tank (not shown) and leading it to the circulation pump 8 are provided. The pipes M4, M5, and M6 are provided with manual valves 16, 17, and 18, respectively. Here, the pipe M6 is a preparation pipe for storing the antifreeze liquid 2 in the cooling tank 3 from the antifreeze liquid storage tank (not shown), and the pipe M5 is the antifreeze liquid 2 stored in the cooling tank 3 after the actual temperature test. Is a pipe for returning to the antifreeze storage tank (not shown).

Further, the antifreeze liquid 2 in the cooling tank 3 is configured to pass through a circulation path that is once guided to the outside, cooled by the heat exchanger 9 provided outside, and returned to the cooling tank 3 again. A specific circulation path is a circulation path of the antifreeze liquid passing through the pipe M1, the pipe M2, the circulation pump 8, the heat exchanger 9, the pipe M3, and the pipe M4. That is, the antifreeze liquid 2 stored in the cooling tank 3 is once led out, cooled by liquid heat exchange with the liquid nitrogen by the heat exchanger 9, and returned to the cooling tank 3 again. On the other hand, the antifreeze liquid 2 in the cooling tank 3 is cooled by liquid nitrogen passing through the pipe L2.
Thus, in the present embodiment, the antifreeze liquid 2 is cooled by liquid nitrogen in the cooling tank 3 and cooled by liquid heat exchange with the external heat exchanger 9. An extremely efficient cooling process is performed.

  In the cooling tank 3, temperature sensors K1 and K2 are provided. The temperature sensor K <b> 1 is a temperature sensor that detects the surface temperature of the pipe L <b> 2 in the cooling tank 3, and is disposed in the vicinity of the pipe L <b> 2 in the cooling tank 3. The temperature sensor K <b> 2 is a temperature sensor that detects the temperature of the antifreeze liquid 2 stored in the cooling tank 3, and is disposed near the upper surface of the antifreeze liquid 2.

  FIG. 4 is a block diagram showing the electrical configuration of the actual temperature test apparatus. In the actual temperature test apparatus 1, the antifreeze liquid 2 is cooled by two types of cooling control methods, timer control and temperature control. More specifically, the cooling is gradually performed by timer control over time at night, and then fine cooling control is performed for a short time by temperature control. By performing the cooling control by the timer control before such temperature control, there is an advantage that the antifreeze liquid can be prevented from freezing.

  Hereinafter, the electrical configuration of the actual temperature test apparatus 1 for performing such control will be described. The actual temperature test apparatus 1 includes a timer control unit 20, a temperature control unit 21, and a main control unit 30. The timer control unit 20 includes a first timer A, a second timer B, a third timer C, an operation input unit 22, and a controller 23. In the cooling control of the timer control unit 20, first, liquid nitrogen is injected for a long time in an initial stage, and then liquid nitrogen is injected for a predetermined time every predetermined injection cycle. In order to perform such control, the first timer A, the second timer B, and the third timer C are used. The third timer C is an initial liquid nitrogen injection time setting timer, and the first timer A is an injection cycle time setting timer for notifying a predetermined injection cycle time after the initial liquid nitrogen injection time has elapsed. The second timer B is an injection time setting timer for injecting liquid nitrogen at every injection period notified by the first timer A.

In the case of a large cooling tank having a required liquid nitrogen amount of 2000 m ³ , the third timer C sets the initial liquid nitrogen injection time from 17:00 to 1 o'clock the next day. The first timer A sets an injection period of 1 hour at 2 o'clock, 3 o'clock, 4 o'clock, 5 o'clock, 6 o'clock, 7 o'clock, and 8 o'clock and 8:30. The second timer B sets the nitrogen injection time to 30 minutes. When the first timer A reaches the injection cycle time (3 o'clock, 4 o'clock, 5 o'clock, 6 o'clock, 7 o'clock, 8 o'clock, 8:30), the first timer A outputs a notification signal to notify that. When the controller 23 receives this notification signal, the second timer B is activated.

  The operation input unit 22 includes operation input keys for setting the first timer A, the second timer B, and the third timer C.

  The temperature control unit 21 includes an operation input unit 24, a temperature control switch 25, a controller 26, a first set temperature storage unit 27 that stores a first set temperature Tm1, and a second setting that stores a second set temperature Tm2. And a temperature storage unit 28. Here, the first set temperature Tm1 is a set value of the surface temperature of the pipe L2 in the cooling tank 3, and the second set temperature Tm2 is a set value of the liquid temperature of the antifreeze liquid 2 stored in the cooling tank 3. In the present embodiment, the first set temperature Tm1 is -120 ° C, and the second set temperature Tm2 is -46 ° C. In the temperature control, the detected temperature T1 of the temperature sensor K1 and the first set temperature Tm1 are compared, the detected temperature T2 of the temperature sensor K2 and the first set temperature Tm2 are compared, and based on this comparison result, the electromagnetic The opening and closing of the on-off valve 7 is controlled, and the cooling is controlled so that the antifreeze liquid 2 reaches the second set temperature Tm2.

  The temperature control switch 25 is a temperature control execution switch. When the temperature control switch 25 is ON, the temperature control is executed. When the temperature control switch 25 is OFF, the temperature control is not executed and the timer control can be executed. It has become. In addition, the opening / closing signal of the electromagnetic opening / closing valve 7 from the controllers 23 and 26 is given to the main control unit 30, and the main control unit 30 performs opening / closing control of the electromagnetic opening / closing valve 7.

  5 to 7 are flowcharts showing the cooling processing operation in the actual temperature test apparatus. In the cooling process in the present embodiment, cooling by timer control (step S1) is performed, and then cooling by temperature control (step S2) is performed.

  A specific process of cooling by the timer control is shown in FIG. First, in step p1, timers A, B, and C are set. Specifically, the operation input unit 22 is operated to set an initial liquid nitrogen injection time (from 17:00 to 1 o'clock on the next day) in the third timer C, and an injection cycle time (2 o'clock, 2 o'clock). 3 o'clock, 4 o'clock, 5 o'clock, 6 o'clock, 7 o'clock, 8 o'clock, 8:30), and the second timer B is set with a nitrogen injection time (30 minutes).

Next, at step p2, it is determined whether or not the operation start time of the third timer C has been reached. That is, it is determined whether or not 17:00 has been reached. If 17:00 is reached, the process proceeds to step p3, and the electromagnetic on-off valve 7 is set to the “open” state. Thereby, the liquid nitrogen stored in the storage tank 6 is supplied to the cooling tank 3. In step p4, it is determined whether or not the operation end time of the third timer C (1 o'clock of the next day) has been reached. If the operation end time of the third timer C has not been reached, the process returns to step p3. When the operation end time of the third timer C is reached, the process proceeds to step p5, and the electromagnetic on-off valve 7 is set to the “closed” state. Thereby, supply to the cooling tank 3 of liquid nitrogen stops.
In this way, the antifreeze liquid 2 is cooled from room temperature to a predetermined cooling temperature (for example, −30 ° C.).

  Next, the process proceeds to step p6, where it is determined whether or not the first timer A has output a signal for informing the injection cycle time. If the notification signal is output, the process proceeds to step p7 to activate the second timer B, In step p8, the electromagnetic on-off valve 7 is set to the “open” state. Thereby, liquid nitrogen is supplied to the cooling bath 3. In step p9, it is determined whether or not the operation time of the second timer B has elapsed (30 minutes, which is the injection time). If the operation time has not elapsed, the process returns to step p8. If the operating time of the second timer B has elapsed in step p9, the electromagnetic on-off valve 7 is set to the “closed” state in step p10. Thereby, supply to the cooling tank 3 of liquid nitrogen stops.

Next, the process proceeds to step p11, where it is determined whether or not the first timer A has notified all the injection cycle times. That is, it is determined whether or not the injection cycle time of 8:00 has already been notified. If not notified, the process returns to step p6, and a series of processing from step p6 to step p11 is repeated. If the injection cycle time of 8:00 has already been notified, the process proceeds to step S2 where temperature control is performed.
Thus, the antifreeze liquid 2 is cooled to a predetermined first cooling temperature range (for example, −30 ° C. to −45 ° C.) by the timer control. Then, as will be described later, cooling is performed with fine control by temperature control from the first cooling temperature range to a set temperature (for example, −46 ° C.).

  The injection cycle times of 2, 3, 4, 5, 6, 6, 7 and 8 are included in the timer control period, and the injection cycle time of 8:30 is included in the temperature control period. That is, in this embodiment, in the temperature control, when the injection cycle time is 8:30, the electromagnetic on-off valve 7 is preferentially opened for 30 minutes.

  Next, a specific process of cooling by temperature control is shown in FIG. In cooling by temperature control, the first set temperature Tm1 and the detected temperature T1 of the temperature sensor K1 are compared at every predetermined timing, and the second set temperature Tm2 and the detected temperature T2 of the temperature sensor K2 are compared and detected. The following processing is performed based on the result.

  First, in step q1, the first set temperature Tm1 and the detected temperature T1 of the temperature sensor K1 are compared, the second set temperature Tm2 and the detected temperature T2 of the temperature sensor K2 are compared, and Tm1 <T1 and Tm2 <T2 In this case, the process proceeds to step q2, the electromagnetic on-off valve 7 is set to the “open” state, and the process returns to step q1. In step q1, if Tm1 <T1 and Tm2 <T2, the process proceeds to step q3, and it is determined whether Tm1 ≧ T1. If so, the process proceeds to step q4, and the electromagnetic on-off valve 7 is set to the “closed” state. Return to step q1.

  In step q3, if Tm1 ≧ T1, the process proceeds to step q5 to determine whether Tm2 ≧ T2, and if so, the process proceeds to step q4. If Tm2 ≧ T2 is not satisfied in step q5, the process returns to step q1.

  In this way, when either one of the detected temperatures T1 and T2 is equal to the set temperature Tm1 or Tm2 or lower than the set temperature Tm1 or Tm2, the electromagnetic on-off valve 7 is set to the “closed” state, and both are set to the set temperature. When it becomes higher, the electromagnetic on-off valve 7 is set to the “open” state. As a result, the antifreeze liquid 2 is cooled to a temperature close to the set temperature (−46 ° C.).

Thus, according to the cooling method according to the present embodiment, the cast steel butterfly valve to be subjected to the actual temperature test is cooled to the vicinity of the actual temperature (−46 ° C.) at which the valve is used, and the temperature is extremely lower than the actual temperature. It can be cooled so as not to cool too much.
In the above embodiment, the switching from the timer control to the temperature control is automatically performed, but it may be configured to be switched manually.

(Other matters)
(1) In the above embodiment, the butterfly valve is exemplified as the low temperature valve. However, a gate valve, a ball valve, a check valve, a ball valve, or other low temperature valves may be used.

  (2) Although the cast steel butterfly valve is illustrated in the above embodiment, a stainless steel butterfly valve may be used.

  (3) In the above embodiment, the antifreeze liquid that does not freeze to −55 ° C. is illustrated, but an antifreeze liquid that does not freeze to a lower temperature range may be used.

  (4) In the above embodiment, two temperature sensors K1 and K2 are used for temperature control, but three or more temperature sensors may be used.

  (5) In the above embodiment, the supply / stop of liquid nitrogen to the cooling tank 3 is performed by the open / close control of the electromagnetic open / close valve 7, but instead of the electromagnetic open / close valve, the opening of the electromagnetic control valve The cooling control may be performed by controlling the above.

  (6) In the above embodiment, a configuration in which the on / off control signal of the electromagnetic on / off valve 7 by the timer control unit 20 and the temperature control unit 21 is output to the main control unit 30, and the main control unit 30 directly controls the electromagnetic on / off valve 7. However, the main control unit 30 is omitted, the timer control unit 20 directly controls the electromagnetic on-off valve 7 during the timer control period, and the temperature control unit 21 directly controls the electromagnetic on-off valve 7 during the temperature control period. Such a configuration may be adopted.

(7) In the above embodiment, the injection cycle time of the first timer A (3 o'clock, 4 o'clock, 5 o'clock, 6 o'clock, 7 o'clock, 8 o'clock in the case of a large cooling tank having a liquid nitrogen requirement of 2000 m ³ 8:30), the nitrogen injection time of the second timer B (30 minutes), and the initial liquid nitrogen injection time of the third timer C (from 17:00 to 1 o'clock of the next day), but the liquid nitrogen requirement amount is 1500 m ^In the case of the medium-sized cooling tank of 3, the initial liquid nitrogen injection time of the third timer C is from 17:00 to 21:00, and the injection cycle time of the first timer A is 22:00, 0:00, 2:00, 4:00, Hours, 7 o'clock, 8 o'clock, 8:30, and the nitrogen injection time of the second timer B is preferably 30 minutes. By setting such a timer, it is possible to prevent the antifreeze liquid from freezing even in the case of a medium-sized cooling tank.

  (8) In the above embodiment, the actual temperature test device for a cast steel butterfly valve is exemplified as the constant temperature bath device according to the present invention. However, the present invention is not limited to this, and the constant temperature bath device used in other fields. Moreover, it can implement suitably.

  The present invention can be applied to a low-temperature thermostat apparatus or the like.

1: Actual temperature test apparatus 2: Antifreeze liquid 3: Cooling tank 4: Butterfly valve 5: Cooling means 6: Storage tank 7: Electromagnetic switching valve 8: Circulation pump 9: Heat exchanger 11, 11a. 11b. 11c: blowing nozzle 20: timer control unit 21: temperature control unit A: first timer B: second timer C: third timer L1-L5, M1-M6: piping K1, K2: temperature sensor

Claims (2)

A thermostat apparatus that has a thermostat and cools the stored fluid stored in the thermostat to a set temperature with a refrigerant,
Circulation piping that draws the stored fluid out of the thermostat and returns it back into the thermostat,
A circulation drive means connected to a circulation pipe and circulatingly driving the stored fluid;
A supply pipe for supplying a coolant for cooling the stored fluid into the thermostat;
A discharge pipe for discharging the refrigerant for cooling the stored fluid to the outside of the thermostatic chamber;
A heat exchanger in which heat is exchanged between the stored fluid passing through the circulation pipe and the refrigerant passing through the discharge pipe;
With
The thermostatic chamber device is provided with at least one or more blowing nozzles, and the blowing nozzles are configured to blow gas toward the stored fluid in the thermostatic chamber.   The discharge pipe is connected to the blowout nozzle, and the refrigerant passing through the discharge pipe is configured to exchange heat with the stored fluid in the heat exchanger so that at least a part thereof is gasified and blown out from the blowout nozzle. Item 2. The thermostatic chamber apparatus according to item 1.

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