JP3407215B2 - Temperature control method of temperature control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature control method for a temperature control device suitable for use in a temperature control device such as a cooling device for cooling a heat generating portion of a machine tool or the like.

[0002]

2. Description of the Related Art Conventionally, a temperature control method for a cooling device which sets an upper limit control temperature and a lower limit control temperature with respect to a target temperature and performs differential control with respect to a detected temperature is disclosed in Japanese Patent Laid-Open No.
It is known from Japanese Patent Laid-Open No. 3-161357.

FIG. 9 shows the temperature characteristic of the cooling liquid (detection temperature To) when the temperature is controlled by the conventional temperature control method when the heat generating portion of the machine tool is cooled by the cooling device.
In the figure, Ts indicates the target temperature, and Tsu and Tsd indicate the upper limit control temperature and the lower limit control temperature in the differential control set for the target temperature Ts, respectively.
With such a setting, the cooling device can detect the temperature T of the coolant.
When o reaches the upper limit control temperature Tsu, the cooling mode is entered, and the detected temperature To is lower limit control temperature Tsd.
When the temperature reaches, the heating mode is entered. Note that Tru and Trd respectively indicate an upper limit specified temperature and a lower limit specified temperature that define the allowable range of temperature fluctuation required for the cooling liquid.

[0004]

In the conventional temperature control method described above, however, the detected temperature To reaches the upper limit control temperature Tsu because of the control and structural response delays in the cooling liquid and the cooling device. Even after shifting to the cooling mode, the detected temperature To exceeds the upper limit control temperature Tsu and overshoots. This means that the detected temperature To is lower limit control temperature Tsd.
The same is true when the temperature is reached to the heating mode, and the detection temperature To exceeds the lower limit control temperature Tsd and undershoots.

Further, the temperature characteristic of the cooling liquid (detection temperature To)
Is greatly affected by the size of the load, and as shown in FIG.
If the load becomes small, it will drift to the low temperature side. As a result,
Since the detected temperature To exceeds the upper limit specified temperature Tru and the lower limit specified temperature Trd that define the allowable range of the temperature fluctuation of the cooling liquid, there is a problem that the accurate and stable temperature control of the cooling liquid cannot be performed.

Therefore, in order to solve this problem, the applicant of the present invention detects the minimum and maximum values of the detected temperature To which are consecutive, and normalizes the average value based on the average value of the minimum and maximum values. Japanese Patent Application Laid-Open No. 9-134220 proposes a temperature control method in which a correction value for matching the target temperature Ts is calculated and the target temperature Ts is corrected by the correction value. According to this temperature control method, the drift of the temperature characteristic (detection temperature To) due to the influence of the load is eliminated, and accurate and stable temperature control can be performed.

However, such a temperature control method has the following points to be improved.

First, in a laser processing machine or the like whose manufacturing quality is directly affected by temperature fluctuations, it is required to reliably suppress temperature fluctuations within an allowable range defined by an upper limit specified temperature and a lower limit specified temperature. The conventional temperature control method cannot sufficiently meet this requirement, and cannot secure a high degree of stability and reliability in temperature control.

Second, in order to prevent the detected temperature from exceeding the upper limit specified temperature (lower limit specified temperature), the difference between the upper limit specified temperature (lower limit specified temperature) and the upper limit control temperature (lower limit control temperature) must be set to a certain degree. Since it cannot be obtained, as shown in FIG. 9, the switching cycle between the cooling mode and the heating mode is shortened, which shortens the service life of the parts and equipment used in the cooling device.

The present invention has solved the problems existing in the prior art as described above, and reliably suppresses temperature fluctuations within an allowable range, ensures a high degree of stability and reliability for temperature control, and uses parts. It is an object of the present invention to provide a temperature control method for a temperature control device that can prolong the life of devices and equipment.

[0011]

Means and Embodiments for Solving the Problems The present invention sets an upper limit specified temperature Tru and a lower limit specified temperature Trd which define an allowable range of temperature fluctuations with respect to a target temperature Ts, and uses the upper limit specified temperature Tru. Lower upper limit control temperature Tsu and lower limit control temperature T higher than the lower limit specified temperature Trd
sd is set, and when the detected temperature To reaches the upper limit control temperature Tsu, the cooling mode is entered, and when the detected temperature To reaches the lower limit control temperature Tsd, the heating mode is entered and the differential control for the detected temperature To is performed. In the temperature control method of the temperature control device 1, an optimum upper limit control temperature Tsu corresponding to an arbitrary rising gradient using a time tu or the like when rising by a constant temperature difference ΔTo in the detected temperature in advance.
... and the optimum lower limit control temperature Tsd corresponding to an arbitrary descending gradient using the time td etc. when descending by a constant temperature difference ΔTo in the detected temperature, the database D is set and detected during temperature control. Detected temperature T
By obtaining the upper limit control temperature Tsua corresponding to the rising gradient of o from the database D and changing the setting of the upper limit control temperature Tsu, and obtaining the lower limit control temperature Tsda corresponding to the falling slope of the detected temperature To detected from the database D. It is characterized in that the lower limit control temperature Tsd is changed.

In this case, according to the preferred embodiment, the setting change of the upper limit control temperature Tsu and the lower limit control temperature Tsd is
The detection temperature To is performed at least once every cycle of rising and falling, and the upper limit control temperature Tsuua is calculated from the database D.
It is desirable to perform immediately after obtaining the lower limit control temperature Tsda and the lower limit control temperature Tsda, and to perform only when the upper limit control temperature Tsua and the lower limit control temperature Tsda obtained from the database D satisfy a preset change permission condition. On the other hand, during temperature control, the upper limit peak temperature Tpu of the detected temperature To is detected to obtain the upper limit correction temperature Xu from the deviation Eu between the upper limit peak temperature Tpu and the upper limit specified temperature Tru.
Based on this upper limit side correction temperature Xu, the upper limit control temperature Tsu
By correcting the lower limit peak temperature Tpd of the detected temperature To and detecting the lower limit peak temperature Tpd of the lower limit peak temperature Tpd.
The lower limit correction temperature Xd is obtained from the deviation Ed between the pd and the lower limit specified temperature Trd, and the lower limit control temperature Tsd is corrected based on this lower limit correction temperature Xd. At this time, the upper limit control temperature Ts
The correction of u is performed every time the upper limit peak temperature Tpu is detected, and after the upper limit peak temperature Tpu is detected until the next upper limit peak temperature Tpu is detected, and the coefficient is Ku. It is possible to obtain the upper limit side correction temperature Xu by (Tru−Tpu) × Ku and add the upper limit side correction temperature Xu to the upper limit control temperature Tsu. The lower limit control temperature Tsd is corrected by the lower limit peak temperature Tpd ...
For each detection, and after detecting the lower limit side peak temperature Tpd and before detecting the next lower limit side peak temperature Tpd, if the coefficient is Kd, then (Trd-Tpd) ×
The lower limit side correction temperature Xd can be obtained from Kd, and the lower limit side correction temperature Xd can be added to the lower limit control temperature Tsd. The temperature control method according to the present invention can be applied to the cooling device 1c that cools the heat generating portion 2.

The principle of the temperature control method according to the present invention is as follows. Normally, when the load is large, the rising gradient of the detected temperature increases, and the rising gradient and the falling gradient of the detected temperature change in accordance with the magnitude of the load. Therefore, in advance, the optimum upper limit control temperature Tsu ... And lower limit control temperature T corresponding to an arbitrary rising slope and an arbitrary falling slope of the detected temperature are set.
Database sd is obtained by calculation or experiment
By constructing as above, at the time of temperature control, the upper limit control temperature Tsua and the lower limit control temperature Tsda corresponding to the actually detected rising gradient and falling gradient of the detected temperature To can be directly obtained from the database D. Therefore, if the setting is changed to the obtained upper limit control temperature Tsua and lower limit control temperature Tsda, the differential control based on the optimum upper limit control temperature Tsua and lower limit control temperature Tsda is always performed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments according to the present invention will be described in detail with reference to the drawings.

First, the cooling device 1c used in the temperature control method according to this embodiment will be described with reference to FIG.

In the figure, M is a machine tool such as a laser processing machine installed in a factory having a heat generating part 2. On the other hand, 1c
Is a cooling device and constitutes the temperature control device 1. This cooling device 1c is provided with a cooling liquid tank 3, and the cooling liquid W contained in this cooling liquid tank 3 is cooled by the circulation pump 4 by the cooling device 1c.
It is supplied to the cooler 5 incorporated in the cooling tank 5, cooled (heat exchanged), and then returned to the cooling liquid tank 3. The cooling device 1c incorporates the cooler 5, the compressor 6, the condenser 7, and the expansion valve (capillary tube) 8 therein to configure a known refrigeration cycle. An on-off valve (CCV) 9 has a function of bypassing the refrigerant gas when the circulation pump 4 is stopped. Further, the cooling liquid W contained in the cooling liquid tank 3 is supplied to the heat generating portion 2 by the pressure feed pump 10 to cool (heat exchange) the heat generating portion 2 and then returned to the cooling liquid tank 3.

On the other hand, a temperature sensor 11 for detecting the temperature of the cooling liquid W is attached inside the cooling liquid tank 3, and the temperature sensor 11 is connected to the control unit 12. The control unit 12 includes a data memory 13 that stores a database D described later. Further, the circulation pump 4 is connected to the control unit 12. As a result, the circulation pump 4 is on / off controlled by the controller 12.

Next, a temperature control method according to this embodiment using such a cooling device 1c will be described with reference to the flow chart shown in FIG. 1 and FIGS.

First, a target temperature Ts (for example, 20 ° C.) is set in the control unit 12, and an upper limit specified temperature Tr for defining an allowable range of temperature variation with respect to the target temperature Ts is set.
u (for example, 21 ° C.) and the lower limit specified temperature Trd (for example,
19 ° C.) and the upper limit control temperature Tsu in the differential control with respect to the target temperature Ts.
(For example, 20.25 ° C.) and the lower limit control temperature Tsd (for example, 19.75 ° C.) are set.

Further, the database D is constructed by obtaining the optimum upper limit control temperatures Tsu ... Corresponding to different rising gradients of the detected temperature and the optimum lower limit control temperatures Tsd ... Corresponding to the falling gradients of different detected temperatures. The database D is stored in the data memory 13. In this case, the ascending slope and the descending slope have a constant temperature difference ΔTo (for example,
Time tu and t when increasing and decreasing by 0.2 ° C.)
d is used. Normally, when the load increases, the rising gradient of the detected temperature increases, so the time tu decreases. On the other hand, when the load becomes large, the upper limit control temperature T is set so that the detected temperature does not exceed the upper limit specified temperature Tru and rises.
It is necessary to set su low, and it is necessary to set the upper limit peak temperature of the detected temperature as close as possible to the upper limit specified temperature Tru so that the switching cycle between the cooling mode and the heating mode becomes longer. That is, since the optimum upper limit control temperature Tsu corresponding to the time tu exists, the optimum upper limit control temperature Tsu corresponding to the time tu is obtained in advance by calculation or experiment. In this case, it is preferable to tentatively correct the tentative data obtained by calculation through experiments. The time td corresponding to the descending gradient and the lower limit control temperature Tsd
The relationship is also similar to the relationship between the time tu and the upper limit control temperature Tsu.

FIG. 3 shows the relationship between the time tu ... And the upper limit control temperature Tsu ... and the time td ... And the lower limit control temperature Tsd.
It is a correlation characteristic indicating the relationship of ... And this correlation characteristic is the content of the database D. Therefore, database D
May be set as a data table, and the corresponding upper limit control temperature Tsua and lower limit control temperature Tsda may be read by inputting the times tu and td, or an arithmetic expression for obtaining the upper limit control temperature Tsua and the lower limit control temperature Tsda may be set. The upper limit control temperature Tsu is stored according to the times tu and td.
It may be possible to calculate a and the lower limit control temperature Tsda.

On the other hand, when the cooling device 1c starts to operate and the detected temperature To of the cooling liquid W detected by the temperature sensor 11 is higher than the target temperature Ts, the cooling mode is set and the control unit 12 controls the circulation. Pump 4 is on, ie
When the detected temperature To is lower than the target temperature Ts while the cooling liquid W is cooled in the operating state, the heating mode is set, the circulation pump 4 is turned off, that is, the operation is stopped, and the cooling liquid W is cooled. Not done.

Now, in FIG. 4, it is assumed that the cooling device 1c is operated in the heating mode. Since the temperature of the coolant W is detected by the temperature sensor 11, the controller 12 monitors the detected temperature To detected by the temperature sensor 11 (step S1). When the detected temperature To rises and reaches the time measurement start temperature, the control unit 12 measures the time tu when it rises by a constant temperature difference ΔTo (steps S2, S).
3). In this case, if ΔTo is set to 0.2 ° C. and the center thereof is set to the target temperature Ts (20 ° C.), the time measurement start temperature becomes 19.9 ° C. Therefore, when the detected temperature To reaches 19.9 ° C., the time measurement is started, and 2
If the time measurement is terminated when the temperature reaches 0.1 ° C., this time measurement time is obtained as time tu.

When the time tu is obtained, the control unit 12 reads the upper limit control temperature Tsua corresponding to the time tu from the database D (step S4). Then, the setting is changed according to the read upper limit control temperature Tsua, that is, the already set upper limit control temperature Tsu is changed to the new upper limit control temperature Tsu.
Change to sua (step S5). Such setting change is performed immediately after obtaining the upper limit control temperature Tsuua from the database D. As a result, even if the upper limit peak temperature Tpu of the detected temperature To that occurs after the setting change is originally much lower than the upper limit specified temperature Tru, the upper limit control temperature Tsu is increased to Tsua, so the upper limit peak temperature Tsu is increased. The temperature Tpu is equal to or lower than the upper limit specified temperature Tru and can approach the upper limit specified temperature Tru.

Further, the detected temperature To is the upper limit control temperature Tsu.
When the temperature reaches a, the cooling mode is entered and the circulation pump 4 starts (turns on) its operation. At this time, the temperature of the cooling liquid W (detection temperature To) rises for a while due to the response delay, and then starts to fall at the peak of the upper limit side peak temperature Tpu. Then, the detected temperature To decreases, and the time measurement start temperature, that is, 20.
When the temperature reaches 1 ° C., the control unit 12 causes the constant temperature difference ΔTo.
The time td when falling by (0.2 ° C.) is measured in the same manner as the case of the time Tu described above (steps S6 and S).
7, S8).

When the time td is obtained, the controller 12 reads the lower limit control temperature Tsda corresponding to the time td from the database D (step S9). Then, the setting is changed according to the read lower limit control temperature Tsda, that is, the already set lower limit control temperature Tsd is changed to the new lower limit control temperature T.
Change to sda (step S10). Such a setting change can be made by changing the lower limit control temperature Tsda from the database D.
Immediately after obtaining. As a result, even if the lower limit peak temperature Tpd of the detected temperature To that occurs after the setting is changed originally falls below the lower limit prescribed temperature Trd, the lower limit control temperature Tsd is increased to Tsda, so that the lower limit side is reached. The peak temperature Tpd is equal to or higher than the lower limit specified temperature Trd and can approach the lower limit specified temperature Trd. When the detected temperature To reaches the lower limit control temperature Tsda, the heating mode is entered, and the circulation pump 4 is stopped (turned off).

The setting change of the upper limit control temperature Tsu is as follows.
It is performed at least once in each cycle in which the detected temperature To rises.
By changing the settings like this, even in a laser processing machine whose manufacturing quality is directly affected by temperature fluctuations, temperature fluctuations are reliably suppressed within an allowable range, and a high degree of stability and reliability for temperature control are secured. It

On the other hand, FIGS. 5 and 6 show different control modes. In FIG. 4, the upper limit side peak temperature Tpu is much lower than the upper limit specified temperature Tru, and the lower limit side peak temperature Tpd falls below the lower limit specified temperature Trd, so that the upper limit control temperature Tsu and the lower limit control temperature Tsd are respectively increased. As shown in FIG.
Is set so that the upper limit side peak temperature Tpu rises above the upper limit prescribed temperature Tru and the lower limit side peak temperature Tpd exceeds the lower limit prescribed temperature Trd, so that the upper limit control temperature Tsu and the lower limit control temperature Tsd are respectively lowered. The case of changing is shown. Also in this case, the temperature fluctuation is surely suppressed within the allowable range as in FIG. 4, and a high degree of stability and reliability for temperature control are secured.

Further, in FIG. 6, since the upper limit side peak temperature Tpu is much lower than the upper limit specified temperature Tru and the lower limit side peak temperature Tpd is also much higher than the lower limit specified temperature Trd, the upper limit control temperature Tsu is changed so as to be higher. In addition, the case where the lower limit control temperature Tsd is changed to a lower setting will be described. In the case of FIG. 6, since the switching cycle between the cooling mode and the heating mode becomes long, it is possible to prolong the service life of the parts and equipment used.

Next, a modified embodiment of the temperature control method according to the present invention will be described with reference to the flow charts shown in FIGS.

Now, in FIG. 4, it is assumed that the cooling device 1c is operated in the heating mode. Since the temperature of the coolant W is detected by the temperature sensor 11, the controller 12 monitors the detected temperature To detected by the temperature sensor 11 (step S11). When the detected temperature To rises and reaches the time measurement start temperature, the control unit 12 measures the time tu at which the temperature rises by a constant temperature difference ΔTo (step S1).
2, S13). The control unit 12 then obtains the obtained time tu
The upper limit control temperature Tsuua corresponding to is read from the database D (step S14). The above is the same as in the basic embodiment of FIG. 1 described above.

On the other hand, in the modified embodiment, it is judged whether or not the preset upper limit control temperature Tsua read from the database D satisfies the preset allowable change condition (step S1).
5). That is, the obtained upper limit control temperature Tsua is compared with the preset upper limit control temperature Tsu, and the setting is changed only when the temperature difference is equal to or more than the set amount, and the setting is not changed when the temperature difference is less than the set amount. . When changing the setting, the preset upper limit control temperature Tsu is changed to a new upper limit control temperature Tsua (step S16).

Further, when the detected temperature To rises and reaches the upper limit control temperature Tsuua, the cooling mode is entered, and the circulation pump 4 starts (turns on) its operation. The temperature of the cooling liquid W (detected temperature To) rises for a while due to the response delay, and then starts to fall at the upper limit peak temperature Tpu as a peak, so the control unit 12 detects the upper limit peak temperature Tpu (step S17, S18). As a result, the control unit 12 calculates the upper limit side correction temperature Xu (step S1).
9). That is, the upper limit side correction temperature Xu is set to Xu = (Tru−
It is calculated from the arithmetic expression of Tpu) × Ku. In this case, Ku is a coefficient and can be set to, for example, about 0.3 to 0.7. When the upper limit correction temperature Xu is obtained, the upper limit control temperature Tsu is corrected by adding the upper limit correction temperature Xu to the upper limit control temperature Tsu (step S2).
0). Such correction of the upper limit control temperature Tsu is performed each time the upper limit peak temperature Tpu ... Is detected. In the example of FIG. 4, the upper limit peak temperature Tpu is much lower than the upper limit specified temperature Tru, so the upper limit control temperature Tsu is increased to Tsub.

On the other hand, the detected temperature To is the upper limit peak temperature T
The temperature starts from pu, and the time measurement start temperature is 20.1 ° C.
When the temperature reaches ΔT, the control unit 12 causes the constant temperature difference ΔTo (0.2
C)), the time td when falling
Measurement is performed in the same manner as in the case of (steps S21, S22, S
23). When the time td is obtained, the control unit 12
Reads out lower limit control temperature Tsda corresponding to time td from database D (step S24).

On the other hand, with respect to the lower limit control temperature Tsda read from the database D, it is determined whether or not a preset change permission condition is satisfied (step S25). That is, the obtained lower limit control temperature Tsda and the preset lower limit control temperature Ts
d is compared, the setting is changed only when the temperature difference is equal to or more than the set amount, and the setting is not changed when the temperature difference is less than the set amount. When changing the setting, the preset lower limit control temperature Ts
d is changed to the new lower limit control temperature Tsda (step S26).

When the detected temperature To further decreases and reaches the lower limit control temperature Tsda, the heating mode is entered and the circulation pump 4 is stopped (turned off). Since the temperature of the cooling liquid W (detected temperature To) falls for a while due to the response delay, and then rises at the peak of the lower limit side peak temperature Tpd,
The control unit 12 detects the lower limit side peak temperature Tpd (steps S27, S28). As a result, the control unit 12
Determines the lower limit side correction temperature Xd by calculation (step S
29). That is, the lower limit correction temperature Xd is set to Xd = (Trd
-Tpd) x Kd. In this case, Kd
Is a coefficient and can be set to, for example, about 0.6 to 0.9. When the lower limit side correction temperature Xd is obtained, the lower limit side correction temperature Tsd is corrected by adding the lower limit side correction temperature Xd to the lower limit control temperature Tsd (step S3).
0). Such correction of the lower limit control temperature Tsd is performed every time the lower limit peak temperature Tpd ... Occurs. In the example of FIG. 4, since the lower limit side peak temperature Tpd is lower than the lower limit prescribed temperature Trd, the lower limit control temperature Tsd is increased to Tsdb.

According to the modified embodiment, more accurate temperature control can be performed. That is, since the database D is fixed data set in advance, it may not always match the actual state depending on the environment or the like. Therefore, more accurate temperature control becomes possible by combining the processes of detecting the respective peak temperatures Tpu and Tpd at the detected temperature To and correcting the upper limit control temperature Tsu and the lower limit control temperature Tsd. Since the processing by such correction is delayed by one cycle, the delay is compensated by the preliminary processing by the setting change using the database D. As described above, in the modified embodiment, the preliminary setting modification process and the highly accurate correction process are combined, so that the synergistic effect of the two makes it possible to perform more accurate and quick temperature control.

The embodiment has been described in detail above.
The present invention is not limited to such an embodiment,
It is possible to arbitrarily change, add, or delete the detailed configuration, numerical values, method, and the like without departing from the scope of the present invention. For example, the rising gradient and the falling gradient have a constant temperature difference ΔT.
Although the case where the times tu and td when rising or falling by o is used is shown, the temperature rising and falling for a certain time may be used, or the rising rate and the falling rate may be used. Further, the setting change is described as being performed once in each cycle in which the detected temperature rises and falls, but may be sequentially performed plural times. Further, the method of changing the setting of the upper limit control temperature Tsu and the lower limit control temperature Tsd only when the preset change permission condition is satisfied may be applied to the basic embodiment of FIG. The correction timing is as follows: after detecting the upper limit peak temperature Tpu (lower limit peak temperature Tpd), the next upper limit peak temperature Tpu (lower limit peak temperature Tpu
It can be performed at any timing until pd) is detected. Further, although the temperature control device 1 is applied to the cooling device 1c for cooling the heat generating portion 2, it can be applied to any other temperature control device 1 such as a heating device.

[0039]

As described above, the temperature control method for the temperature control device according to the present invention is suitable for optimally responding to an arbitrary rising gradient using the time when the temperature rises by a certain temperature difference in advance. The database is set by finding the optimum lower limit control temperature corresponding to an arbitrary descending gradient using the time when the temperature falls by a certain temperature difference between the upper limit control temperature and the detected temperature, and the detected temperature detected during temperature control is set. Change the setting of the upper limit control temperature by obtaining the upper limit control temperature corresponding to the rising gradient of the temperature from the database, and change the setting of the lower limit control temperature by obtaining the lower limit control temperature corresponding to the falling gradient of the detected detected temperature from the database. As a result, the following remarkable effects are achieved.

Even in a laser processing machine or the like whose manufacturing quality is directly affected by temperature fluctuations, temperature fluctuations can be reliably suppressed within an allowable range, and high stability and reliability for temperature control can be secured.

In addition to ensuring the above, the switching cycle between the cooling mode and the heating mode can be lengthened, so that the life of the parts and equipment used can be extended.

According to a preferred embodiment, during temperature control, the upper limit peak temperature of the detected temperature is detected to obtain the upper limit correction temperature from the deviation between the upper limit peak temperature and the upper limit specified temperature, and the upper limit correction temperature is calculated. By correcting the upper limit control temperature based on the temperature and detecting the lower limit peak temperature of the detected temperature, the lower limit correction temperature is calculated from the deviation between the lower limit peak temperature and the lower limit specified temperature. If the lower limit control temperature is corrected based on this, the preliminary setting change process and the highly accurate correction process are combined, so that a more accurate and quick temperature control can be performed by the synergistic effect of both.

[Brief description of drawings]

FIG. 1 is a flowchart showing a processing procedure of a temperature control method according to an embodiment of the present invention,

FIG. 2 is a block configuration diagram of a cooling device capable of implementing the same temperature control method,

FIG. 3 is a correlation characteristic diagram showing the contents of a database used for implementing the temperature control method.

FIG. 4 is a change characteristic diagram of the detected temperature when the temperature is controlled by the same temperature control method,

FIG. 5 is another change characteristic diagram of the detected temperature when the temperature is controlled by the same temperature control method,

FIG. 6 is a diagram showing another change characteristic of the detected temperature when the temperature is controlled by the same temperature control method.

FIG. 7 is a first half flow chart showing a processing procedure of a temperature control method according to a modified embodiment of the present invention;

FIG. 8 is a latter half flow chart showing a processing procedure of a temperature control method according to the modified embodiment;

FIG. 9 is a change characteristic diagram of the detected temperature when the temperature is controlled by the temperature control method according to the related art,

[Explanation of symbols]

1 Temperature controller 1c Cooling device 2 heating part Ts target temperature To detection temperature Tru upper limit specified temperature Trd lower limit specified temperature Tsu upper limit control temperature Tsd lower limit control temperature Tsuua upper limit control temperature Tsda lower limit control temperature Tpu upper limit peak temperature Tpd lower limit peak temperature Eu Deviation between upper limit peak temperature and upper limit specified temperature Ed Deviation between lower limit peak temperature and lower limit specified temperature Xu Upper limit correction temperature Xd Lower limit correction temperature D database ΔTo constant temperature difference tu time td time

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shinya Maruyama Shinya Maruyama 246 Kodaka, Suzaka City, Nagano Orion Machinery Co., Ltd. (56) Reference JP-A-9-134220 (JP, A) JP-A-4- 335977 (JP, A) JP-A-53-115490 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G05B 23 / 00-23 / 32

Claims (9)

(57) [Claims] 1. An upper limit specified temperature and a lower limit specified temperature that define an allowable range of temperature fluctuations with respect to a target temperature are set, and an upper limit control temperature lower than the upper limit specified temperature and a lower limit control higher than the lower limit specified temperature. Set the temperature, if the detected temperature reaches the upper limit control temperature, shift to the cooling mode,
When the detected temperature reaches the lower limit control temperature, the temperature control method moves to the heating mode and performs a differential control for the detected temperature in the temperature control method of the temperature controller, in advance, the time when the temperature difference increases by a certain temperature difference. By determining the optimum upper limit control temperature corresponding to an arbitrary ascending gradient and the optimum lower limit control temperature corresponding to an arbitrary descending gradient using the time when falling by a certain temperature difference in the detected temperature, etc. A database is set, and during temperature control, the upper limit control temperature corresponding to the rising gradient of the detected temperature detected is obtained from the database to change the setting of the upper limit control temperature, and the lower limit control corresponding to the falling gradient of the detected temperature detected. The temperature of the temperature controller is characterized in that the lower limit control temperature is changed by obtaining the temperature from the database. Control method. 2. The setting change of the upper limit control temperature and the lower limit control temperature is performed at least once in each cycle of rising and falling of the detected temperature, and the upper limit control temperature and the lower limit control temperature are obtained from the database. The temperature control method of the temperature control device according to claim 1, wherein the temperature control method is performed immediately after that. 3. The setting change of the upper limit control temperature and the lower limit control temperature is performed only when the upper limit control temperature and the lower limit control temperature obtained from the database satisfy a preset change permission condition. Item 2. A temperature control method for a temperature controller according to Item 1. 4. An upper limit correction temperature is obtained from a deviation between the upper limit peak temperature and the upper limit specified temperature by detecting an upper limit peak temperature of the detected temperature during temperature control.
By correcting the upper limit control temperature based on the upper limit side correction temperature and detecting the lower limit side peak temperature of the detected temperature, the lower limit side correction temperature is obtained from the deviation between the lower limit side peak temperature and the lower limit specified temperature. The temperature control method of the temperature controller according to claim 1, wherein the lower limit control temperature is corrected based on the lower limit side correction temperature. 5. The correction of the upper limit control temperature is performed every time the upper limit peak temperature is detected and after the upper limit peak temperature is detected until the next upper limit peak temperature is detected. Item 5. A temperature control method for a temperature control device according to Item 4. 6. When the upper limit specified temperature is Tru, the upper limit side peak temperature is Tpu, and the coefficient is Ku, (Tru-
6. The temperature according to claim 4, wherein the upper limit correction temperature is calculated by (Tpu) × Ku, and the upper limit correction temperature is added to the upper limit control temperature to correct the upper limit control temperature. Temperature control method for controller. 7. The lower limit control temperature is corrected every time the lower limit peak temperature is detected, and after the lower limit peak temperature is detected until the next lower limit peak temperature is detected. Item 5. A temperature control method for a temperature control device according to Item 4. 8. If the lower limit specified temperature is Trd, the lower limit side peak temperature is Tpd, and the coefficient is Kd, then (Trd-
8. The temperature according to claim 4, wherein the lower limit side correction temperature is calculated by Tpd) × Kd, and the lower limit side correction temperature is added to the lower limit control temperature to correct the lower limit control temperature. Temperature control method for controller. 9. The temperature control method for a temperature controller according to claim 1, wherein the temperature control method is applied to a cooling device for cooling a heat generating portion.