JP3326629B2 - Micro temperature control device and method - 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 apparatus for keeping the environment of an apparatus having a strict temperature control such as an exposure apparatus constant.

[0002]

2. Description of the Related Art A conventional temperature control device has a configuration shown in FIG. That is, a cooling coil (also referred to as an evaporator or an evaporator in a refrigeration cycle) for cooling the temperature control medium 1, a refrigerator 2 including a compressor and a condenser, an expansion valve 3, and a connection between each member. Are connected to each other to form a refrigeration cycle from refrigerant pipes 4a, 4b, and 4c that serve as refrigerant passages. Cooling coil 1 close to cooling coil 1
A variable-capacity heater 5 having the above capacity (temperature-raising capacity)
Is provided. The temperature control medium 6 flowing in a certain direction by a fan (not shown) undergoes heat exchange via the cooling coil 1 and the heater 5 and is sent into a chamber (not shown).
A temperature sensor 7 for detecting the temperature of the temperature control medium 6 from the heater 5 is provided for detecting the temperature of the temperature control medium 6 passing through the heater 5. The detected temperature information of the temperature sensor 7 enters a temperature controller 8, and the temperature controller 8 controls the heater 5 based on the detected temperature information so that the detected temperature of the temperature sensor 7 becomes a set temperature from an input device (not shown). (The temperature of the heater 5 is controlled).

[0003]

In the prior art as described above, the temperature control is performed by variably controlling a large-capacity heater, so that the resolution is increased. There was a problem that the variation became large. The present invention has been made in view of such conventional problems,
An object of the present invention is to reduce temperature variations when performing minute temperature control.

[0004]

In order to solve the above problems,
The temperature control device according to the present invention includes a cooling coil for a refrigeration cycle.
(1) Cooling the temperature control medium (6) through the temperature control
Temperature control to adjust to a predetermined temperature through a controllable heater
Control device, wherein the heater is a first heater (5
0) and a second heater having a smaller capacity than the first heater.
(51), and of the two heaters
By adjusting at least the capacity of the second heater (51),
Temperature control means (8) for controlling the temperature of the medium
It is characterized by the following. Further, the temperature control method of the present invention
Is the temperature cooled through the cooling coil of the refrigeration cycle
Pass the control medium through a temperature-controllable heater
Temperature control method, wherein the heater is
1 heater and less power than its 1st heater
A second heater, and of the two heaters
At least adjust the capacity of the second heater to reduce the medium
It is characterized by controlling the temperature.

[0005]

According to the present invention, at least the capacity of the small capacity heater
, The resolution of the heater capacity to be controlled is improved, and the temperature variation during minute temperature control can be reduced.

[0006]

FIG. 1 is a block diagram showing an embodiment of the present invention.
The configuration of the embodiment of FIG. 1 differs from the conventional example of FIG. 2 only in the configuration of the heaters 50 and 51, and the other components are the same as those of the conventional example. The primary heater 50 is a large-capacity heater having a larger capacity than the secondary heater 51,
The secondary heater 51 is a small capacity heater having a smaller capacity than the primary heater 50. The primary heater 50 has a fixed capacity, while the secondary heater 51 has a variable capacity so that the capacity can be controlled by the temperature controller 8. The temperature controller 8 taking in the information from the temperature sensor 7 performs a difference calculation with a set temperature from an input device (not shown) to determine the capability of the variable-capacity secondary heater 51 and controls the secondary heater 51. I do. The temperature control medium 6 is controlled by the cooling coil 1 of the refrigeration cycle including the refrigerant pipe 2a, the refrigerator 2, the refrigerant pipe 4b, the expansion valve 3, the refrigerant pipe 4c, and the cooling coil 1.
After the cooling, the primary heater 50 having a fixed capacity is heated to a temperature slightly lower than the set temperature. The temperature control medium 6 is further heated by a secondary heater 51 whose capacity is adjusted by the temperature controller 8, and is corrected to a set temperature.

[0007] The temperature control medium (for example, air) 6 corrected to the set temperature in this manner is introduced into a chamber room in which an exposure apparatus or the like is installed. In the embodiment of FIG.
Since the small-capacity secondary heater 51 is variable and the large-capacity primary heater 50 is fixed, fine temperature control of the temperature control medium 6 (for example, in 0.01 ° C. units) can be performed.
When the primary heater 50 has a variable capacity, and the temperature controller 8 determines that the difference between the temperature information from the temperature sensor 7 and the set temperature is larger than a predetermined temperature range, the primary heater 50 is controlled to control the primary heater 50 to a predetermined temperature range. After driving inside, secondary heater 5
1 may be controlled to match the set temperature.

The cooling coil 1 and the heaters 50 and 51
Is preferably arranged as close as possible in order to reduce the influence of disturbance. Implementation of the present invention as described above
According to the example, the resolution per unit of the temperature controller is improved,
The effect of reducing temperature unevenness when performing small temperature control
There is. For example, the heating of the heater 5 of FIG.
The capacity was set to 3000 Kcal / H, and 1 in FIG.
The heating capacity of the secondary heater 50 is 2400 Kcal / H,
When the heating capacity of the secondary heater 51 is 600 Kcal / H
In addition, the resolution equivalent to 1% of the temperature controller 8 is 5 times as large as the conventional one.
Control can be performed with the appropriate accuracy.

[0009]

As described above, according to the present invention, a minute temperature
Temperature variation during temperature control can be reduced
You.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a block diagram of a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooling coil 2 Refrigerator 3 Expansion valve 4a, 4b, 4c Refrigerant piping 5 Heater 6 Temperature control medium 7 Temperature sensor 8 Temperature controller 50 Primary heater 51 Secondary heater

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G05D 23/00-23/32 F24H 11/00-11/02 F25B 29/00

Claims (12)

(57) [Claims] 1. A temperature control medium cooled through a cooling coil of a refrigeration cycle is passed through a temperature-controllable heater,
In a temperature control device for adjusting to a predetermined temperature, the heater includes a first heater and the first heater
And a second heater smaller capacity than over, at least a second heater of the two heaters
Temperature control means for controlling the temperature of the medium by adjusting the capacity of the medium
Fine temperature control apparatus characterized by having a. 2. The temperature controlled by the second heater.
Detecting means for detecting the temperature information of the medium.
And the temperature control means detects the temperature information detected by the detection means.
The capacity of at least the second heater based on the
The minute temperature control according to claim 1, wherein
apparatus. 3. The temperature control means according to claim 2, wherein
The temperature of the medium whose temperature is controlled by the
So that the temperature of the second heater is at least
3. The micro temperature according to claim 2, wherein the force is adjusted.
Degree control device. 4. The temperature control means according to claim 1 , wherein the difference between the temperature of the medium controlled by the second heater and the predetermined temperature is larger than a predetermined temperature range. 4. The minute temperature control device according to claim 2, wherein the temperature is adjusted to fall within a predetermined temperature range. 5. The micro temperature control device according to claim 1, wherein the micro temperature control device is arranged in a flow path of the refrigerant before introducing the refrigerant into a device to be temperature controlled. 2. The micro temperature control device according to 1. Wherein should said temperature control device, fine temperature control device according to claim 5, characterized in that it comprises an exposure apparatus. 7. A temperature control medium cooled through a cooling coil of a refrigeration cycle is passed through a temperature controllable heater.
In the temperature control method for adjusting the temperature to a predetermined temperature, the heater includes a first heater and a second heater having a smaller capacity than the first heater, and at least a second heater among the two heaters. A minute temperature control method, comprising controlling the temperature of the medium by adjusting the capacity of a heater. 8. The apparatus according to claim 7 , wherein temperature information of the medium whose temperature is controlled by the second heater is detected, and at least the capacity of the second heater is adjusted based on the detection result. 3. The micro temperature control method according to 1. 9. The apparatus according to claim 8, wherein at least the capacity of the second heater is adjusted so that the temperature of the medium whose temperature is controlled by the second heater becomes a predetermined set temperature. Micro temperature control method. 10. When the difference between the temperature and the predetermined set point temperature of the medium is temperature controlled by the second heater is greater than the predetermined temperature range, by adjusting the capacity of the first heater The method according to claim 8, wherein the temperature is controlled within a predetermined temperature range. 11. The microscopic device according to claim 7, wherein the temperature of the refrigerant is controlled in a flow path of the refrigerant before the refrigerant is introduced into a device to be temperature-controlled. Temperature control method. 12. The method according to claim 11, wherein the apparatus to be temperature-controlled includes an exposure apparatus.