JP2002023861A - Two position controller and temperature controller and fluid supplying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly precisely control the supply temperature of fluid to be supplied to a load circuit, and to miniaturize a buffer tank. SOLUTION: A fluid supplying device 10 is provided with a present temperature sensor 31 arranged on the upstream side than a buffer tank 14 for detecting present temperature PV of cooled fluid and a controller 30 for outputting a on/off signal to a cooler 12. The controller 30 integrates temperature deviation between set temperature SV and present temperature PV of fluid to be supplied to the load circuit 20, and outputs the on/off signal to the cooler so that the integrated value of the deviation while the on-signal is outputted to the cooler and the integrated value of the deviation while the off-signal is outputted can be made fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a two-position control device,
The present invention relates to a temperature control device and a fluid supply device.

[0002]

2. Description of the Related Art There is a fluid supply device to which a two-position control device or a temperature control device is applied. A general fluid supply device includes a cooler that cools circulating brine, a circuit that circulates brine through a load circuit in which a work is arranged, and a buffer tank that is arranged in the circuit and compresses temperature fluctuations of the brine. . In the fluid supply device, the temperature of the workpiece is controlled to the set temperature by adjusting the supply temperature of the brine supplied to the load circuit to a predetermined temperature.

By the way, P.P.
ID calculation control is generally used. However, the PID calculation control has a disadvantage that it takes a relatively long time to reach the set temperature in the case of high-precision temperature control, that is, when controlling the fluid temperature with a small temperature range.

On the other hand, two-position control (also referred to as on-off control) is used as a temperature control method for reaching a set temperature in a short time. However, two-position control
Since the temperature control range is relatively large, it is not suitable for high-precision temperature control.

In the two-position control, as shown in FIG. 6, when the supply temperature of the brine reaches the fluid set temperature SV, a manipulated variable of 0% (off) is output to the cooler, and the operation of the cooler is turned off. I do. When the supply temperature of the brine rises above the fluid set temperature SV by the preset adjustment sensitivity, an operation amount of 100% (ON) is output to the cooler, and the operation of the cooler is turned on again. Thus, on / off switching is
This is performed at two points: a point at which the brine supply temperature becomes the fluid set temperature SV, and a point obtained by subtracting the adjustment sensitivity from the fluid set temperature SV.

As shown in FIG. 7, in a conventional buffer tank 50 disposed on the outlet side of the cooler, the inside of the tank 50 is agitated by the flow velocity of the circulating brine so as to compress fluctuations in temperature.

[0007]

In the two-position control, since the on-off operation is repeated at the two temperatures, if the temperature fluctuation between the two temperatures is compressed by using a buffer tank, it is relatively large. There is a problem that a buffer tank having a large capacity is required. Further, even if the brine temperature can be relatively stabilized by using a large-capacity buffer tank, the temperature deviation from the fluid set temperature SV cannot be made zero, and a steady deviation remains.

Further, in a system in which the inside of the tank 50 is agitated by the flow velocity of the circulating brine to compress the temperature fluctuation as in the conventional buffer tank 50, the tank 50
The position and size of the vortex generated inside changes over time,
There is a problem that the outlet temperature of the brine derived from the buffer tank 50 is not stable. Further, in order to accurately control the temperature of the brine supplied to the load circuit, a large-capacity buffer tank is required, which hinders the miniaturization of the fluid temperature control device.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems associated with the conventional technique, and has as its object to provide a two-position control device capable of controlling a state to be adjusted by a controlled object with high accuracy. .

It is another object of the present invention to provide a temperature control device capable of controlling a temperature in a state to be adjusted by a heat source unit with high accuracy.

It is another object of the present invention to provide a fluid supply device capable of controlling the temperature of the fluid supplied to the load circuit with high accuracy and reducing the size of the buffer tank.

It is still another object of the present invention to provide a fluid supply device which stabilizes the outlet temperature of the fluid led out of the buffer tank and reduces the size of the buffer tank.

[0013]

The present invention for achieving the above object is constituted as follows for each claim.

(1) A control target part whose operation is on-off controlled, a current value detection part for detecting a current value in a state adjusted by the control target part, and a set value of a state to be adjusted by the control target part And an integrated value of the deviation while outputting an ON signal to the control target unit, and an integral of the deviation while outputting an OFF signal to the control target unit. A control unit that outputs an on-off signal to the control target unit so that the value becomes constant.

(2) A heat source section whose operation is on / off controlled, a current temperature detecting section for detecting a current temperature in a state adjusted by the heat source section, a set temperature in a state to be adjusted by the heat source section, and the current temperature. The temperature deviation from the temperature is integrated, and the integral value of the deviation while outputting the ON signal to the heat source unit and the integral value of the deviation while outputting the OFF signal to the heat source unit are constant. And a control unit that outputs an on-off signal to the heat source unit.

(3) A heat source section that cools or heats the circulating fluid and is controlled to be on and off, a buffer tank into which the fluid cooled or heated by the heat source section is introduced, and a fluid derived from the buffer tank. And a circuit for circulating the load (W) to a load circuit in which the load (W) is circulated. A current temperature detection device for detecting a current temperature of a cooled or heated fluid, which is disposed upstream of the buffer tank. Unit, integrates the temperature deviation between the set temperature of the fluid supplied to the load circuit and the current temperature, the integrated value of the deviation while outputting an ON signal to the heat source unit, and the heat source unit And a control unit that outputs an on-off signal to the heat source unit so that an integral value of the deviation during output of the off signal is constant. It is the location.

(4) A heat source section which cools or heats the circulating fluid and is controlled to be on / off, a buffer tank into which the fluid cooled or heated by the heat source section is introduced, and a fluid drawn out of the buffer tank. A circuit that circulates a load circuit in which a load is disposed, in the fluid supply device, a current temperature detection unit that is disposed upstream of the buffer tank and detects a current temperature of the cooled or heated fluid, A flow rate detector that detects the circulating flow rate of the fluid, integrates a value obtained by integrating the circulating flow rate with a temperature deviation between a set temperature of the fluid supplied to the load circuit and the current temperature, and outputs an ON signal to the heat source unit. The on-off signal to the heat source unit so that the integral value while outputting the signal and the integral value while outputting the off signal to the heat source unit are constant. A control unit for force, a fluid supply apparatus characterized by having a.

(5) A heat source section that cools or heats the circulating fluid and is controlled to be turned on and off, a buffer tank into which the fluid cooled or heated by the heat source section is introduced, and a fluid drawn from the buffer tank. And a circuit for circulating a load through a load circuit, wherein the buffer tank has a rectifier having an inlet for introducing the fluid, an outlet for extracting the fluid, and a plurality of through holes. And a fluid flowing out of each of the through-holes of the flow straightening means in a laminar flow state toward the outlet.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a fluid supply device to which a two-position control device and a temperature control device according to the present invention are applied will be described below with reference to the drawings.

[First Embodiment] FIG. 1 is a configuration diagram showing a fluid supply device according to a first embodiment.

The fluid supply device 10 is connected to a load circuit 20 in which a work W as a constant temperature object is arranged.
The brine flows in a closed circuit. That is, the brine is supplied from the fluid supply device 10 to the load circuit 20,
After adjusting the temperature of the work W, the work W is returned to the fluid supply device 10 again. The operation of the fluid supply device 10 is controlled by a controller 30 as a control unit.

As the brine, for example, ethylene glycol, a refrigerant, pure water, water or the like is used, and a brine according to the work W is selected. The heat source for cooling or heating the brine is appropriately selected according to the set temperature of the work W. For example, when the set temperature of the work W is relatively low, a cooler is used as a heat source and the brine is cooled by a refrigerant. When the set temperature of the work W is relatively high, a heater such as an electric heater is used as a heat source, and the brine is heated by Joule heat. In the case of a cooler, the controller 30 controls the operation of the compressor that discharges the refrigerant on and off. In the case of an electric heater, the controller 30 performs on-off control of a switching element such as an SSR (solid state relay). An embodiment having a cooler as a heat source will be described.

More specifically, the illustrated fluid supply apparatus 10 exchanges heat between a refrigerant and brine by a cooler 12 (corresponding to a heat source) having a compressor 11 driven by a motor to discharge the refrigerant. A heat exchanger 13 for cooling the brine, a buffer tank 14 for temporarily storing the brine, and a pump 15 for circulating the brine.
And a supply port 16 for supplying brine to the load circuit 20
And a return port 17 for returning the brine that has passed through the load circuit 20, and a plurality of pipes 19 for connecting these components.
a to 19d (corresponding to a circuit).

The fluid supply device 10 is configured so as not to change the flow rate of brine during its operation.
For this reason, a pump capable of sending out a brine with a constant flow rate is used as the pump 15. However,
In order to meet various specifications required for the fluid supply device 10, a pump 15 capable of changing the set value of the brine flow rate may be used.

The load circuit 20 is incorporated in a manufacturing device, an inspection device, a constant temperature device, or the like. The load circuit 20 has an inlet pipe 21 connected to the supply port 16, a chamber 22 in which the work W is stored, and an outlet pipe 23 connected to the return port 17. The work temperature is adjusted to the set temperature by the brine supplied to the chamber 22.

The pipe 19a is provided with a current temperature sensor 31 (corresponding to a current temperature detector) for detecting the current temperature PV of the brine cooled while flowing through the heat exchanger 13. A supply temperature sensor 32 for detecting a supply temperature Pt of the brine supplied to the load circuit 20 is provided in the pipe 19c.
Is provided. Each of the sensors 31 and 32 includes a resistance temperature detector, a thermocouple, and the like.

FIG. 2 is a block diagram showing the configuration of the controller 30 for controlling the operation of the fluid supply device 10.

A current temperature sensor 31 and a supply temperature sensor 32 are connected to the CPU 33, and the brine current temperature P
Each of the V detection signal and the brine supply temperature Pt detection signal is input. Further, a setting unit 34, a ROM 35, a RAM 36, a timer 37, and the like are connected to the CPU 33. The setting unit 34 includes an input device such as a numeric keypad, and sets the supply setting temperature SV of the brine. The ROM 35 stores various parameters and programs necessary for controlling the operation of the fluid supply device 10.

Then, the CPU 33 outputs to the compressor 11 a two-position signal, that is, an operation amount of 100% (on) or 0% (off), based on the current brine temperature PV and the set supply temperature SV. Chiller 12
Turn on or off the operation of.

Next, referring to FIG.
A description will be given of the control of the temperature of brine by 0.

FIG. 3A is a diagram showing a change in the temperature of the brine when the on / off control is performed, FIG. 3B is a diagram showing a change in the on / off output, and FIG. 3C is a diagram showing the supply temperature sensor. FIG. 7 is a diagram showing a change in the brine supply temperature Pt detected by the method shown in FIG.

When the operation of the fluid supply device 10 is started, since the brine current temperature PV is higher than the set supply temperature SV, the controller 30 outputs an operation amount of 100% (ON) to the compressor 11 and Turn on the operation.

When the brine current temperature PV decreases with the operation of the cooler 12 and reaches the supply set temperature SV (time t).
0), the integration of the temperature deviation between the brine supply set temperature SV and the current temperature PV is started. The time when the integrated value becomes S is defined as t1 (formula (1) below). Where S is
It is a parameter that can be changed, and the user can set an arbitrary value.

[0034]

(Equation 1)

When the integral value becomes S in the above equation (1) (time t1), the controller 30 sets 0% (off).
Is output to the compressor 11 and the operation of the cooler 12 is turned off. Further, the integration of the temperature deviation is started again.
The time when the integrated value becomes S is defined as t2 (formula (2) below).

[0036]

(Equation 2)

The controller 30 outputs an operation amount of 100% (ON) to the compressor 11 at the same time when the integral value becomes S in the above equation (2) (time t2), and the controller 12
Turn on the operation of. Further, the integration of the temperature deviation is started again. The time when the integrated value becomes S is defined as t3 (formula (3) below).

[0038]

(Equation 3)

Similarly, the controller 30 sets 0 at the same time when the integral value becomes S in the above equation (3) (time t3).
The operation amount of% (off) is output to the compressor 11, and the operation of the cooler 12 is turned off. Further, the integration of the temperature deviation is started again. The time when the integral value becomes S is defined as t4 (formula (4) below).

[0040]

(Equation 4)

The controller 30 repeatedly executes the above-described calculation, outputs an on-off operation amount, and controls the temperature of the brine. In other words, the controller 30 integrates the temperature deviation between the supply set temperature SV of the brine and the current temperature PV, and outputs an integrated value of the deviation during the output of the ON signal to the cooler 12 and the OFF signal. An on-off signal is output to the cooler 12 so that the integral value of the deviation between the two becomes constant.

According to the integral operation type two-position control described above, there is an essential advantage of the two-position control that the current temperature PV of the brine introduced into the buffer tank 14 reaches the set temperature at high speed. Needless to say, the current temperature PV changes regularly with a small temperature control width. When the brine flow rate is constant, the integral value S corresponds to a constant value of heat. Therefore, by completely agitating the brine in the buffer tank 14, FIG.
As shown in (C), the supply temperature Pt of the brine supplied to the load circuit 20 is controlled to the set temperature SV without causing overshoot or undershoot. In particular, even when the load fluctuates from 0 to 100%, the accuracy of the temperature control can be kept high.

When ethylene glycol as a brine was circulated at a fixed flow rate of 10 liters / minute, the supply set temperature SV was 5 irrespective of the load-side conditions.
The current temperature P which is the control temperature in the range of
V could be stabilized within the “supply setting temperature SV ± 0.1 ° C.”.

Further, since the current temperature PV of the brine introduced into the buffer tank 14 has a small temperature control width and changes regularly, even if the buffer tank 14 has a relatively small capacity, Tank 14
Can reduce the fluctuation of the brine outlet temperature derived from
The temperature deviation from the fluid set temperature SV can be made substantially zero. Since the buffer tank 14 can be made smaller,
The overall size of the fluid supply device 10 can be reduced.

Furthermore, parameter setting is easier than in PID control, and adjustment time for temperature control is unnecessary or reduced, so that user's labor and load can be reduced.

[Second Embodiment] FIG. 4 is a configuration diagram showing a fluid supply device according to a second embodiment. Members common to those shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be partially omitted.

The fluid supply device 10a according to the second embodiment
Is based on the assumption that the circulating flow rate of the brine fluctuates. In addition to the configuration of the fluid supply device 10 of the first embodiment,
A flow sensor 38 (corresponding to a flow detection unit) for detecting the circulating flow rate F of the brine is provided in the return pipe 19d. The flow sensor 38 includes a general flow meter using an orifice, and a controller 30 that converts a measured value into an electric signal and
and a converter for outputting to a. A detection signal of the brine circulation flow rate F is input to the CPU 33.

In the second embodiment, the controller 3
0a is a value obtained by integrating a value obtained by integrating the circulating flow rate (F) into the temperature deviation between the supply setting temperature SV of the brine and the current temperature PV, and outputting an ON signal to the cooler 12, and an OFF signal. So that the integral value during the output of
An on-off signal is output to the cooler 12.

When the controller 30a outputs the operation amount of 100% (ON) to the compressor 11 at the time t _n , the controller 30a calculates an integral value while outputting the ON signal.
The time when the integrated value becomes S is defined as t _{n + 1} (formula (5) below).

[0050]

(Equation 5)

When the controller 30 outputs an operation amount of 0% (off) to the compressor 11 at time t _{n + 1} , the controller 30 calculates an integral value while the off signal is being output. The time when the integrated value becomes S is defined as t _{n + 2} (formula (6) below).

[0052]

(Equation 6)

If the brine circulating flow rate F becomes zero during the calculation of the integral value, an operation amount of 0% (off) is output to the compressor 11.

Even in the above-described two-position control of the heat capacity integration operation type, the supply temperature Pt of the brine supplied to the load circuit 20 is set without causing overshoot or undershoot, as in the first embodiment. Even when the load is controlled at the temperature SV and the load fluctuates from 0 to 100%, the accuracy of the temperature control can be maintained at a high level.

Further, the buffer tank 1 having a relatively small capacity is used.
Even with 4, the fluctuation of the outlet temperature of the brine derived from the buffer tank 14 can be compressed, and the temperature deviation from the fluid set temperature SV can be made almost zero. Through the miniaturization of the buffer tank 14, the fluid supply device 1
0a can be downsized. Further, the user's labor and load can be reduced.

[Third Embodiment] FIG. 5 is a configuration diagram showing a buffer tank of a fluid supply device according to a third embodiment. Note that the overall configuration of the fluid supply device is the same as in the first and second embodiments, and is not illustrated.

The illustrated buffer tank 40 can be used in combination with the fluid supply devices 10 and 10a of the respective embodiments that execute the above-described integral operation type two-position control, and can be used in general for executing the conventional two-position control. It can be used in combination with a fluid supply device.

The buffer tank 40 has an upper opening 41a.
Are formed, a lid 42 for closing the upper opening 41a, and rectifying means 43 disposed horizontally in the upper part of the body 41. The pipe 19 is provided on the upper surface of the lid 42.
An inlet 44 is provided to which a is connected, and an outlet 45 to which the pipe 19 b is connected is provided on the lower surface of the body 41.

The rectifying means 43 comprises a partition plate 47 in which a number of small through holes 46 are formed. Each through hole 4
The brine that has flowed out of 6 becomes laminar and becomes the outlet portion 45.
The size and number of the through-holes 46 are such that
The flow rate of the brine flowing out of each through hole 46 is 2-3 cm.
/ Sec.

The buffer tank 40 through the inlet 44
As described above, the temperature of the brine at the time of flowing into the inside, that is, the current temperature PV which is the control temperature has a certain degree of deviation from the fluid set temperature SV (in the above-described first and second embodiments, , About ± 0.1 ° C). The brine having a temperature higher than the supply set temperature SV and the brine having a temperature lower than the supply set temperature SV alternately flow out of the through holes 46 and flow toward the outlet 45 in a laminar state.

Then, at the outlet 45, the brine having a temperature higher than the supply set temperature SV and the brine having a temperature lower than the supply set temperature SV are efficiently mixed, and the temperature fluctuation when flowing into the buffer tank 40 is reduced. Is done. As a result, the temperature deviation of the brine derived from the outlet 45 from the fluid set temperature SV becomes substantially zero. This brine is guided to the pump 15 and supplied to the load circuit 20.

Focusing on the fact that the brine having a temperature higher than the supply set temperature SV and the brine having a temperature lower than the supply set temperature SV flow alternately, the capacity of the buffer tank 40 is defined as one cycle of the operation output on-off. If the minimum volume of brine circulating during the average time of
Temperature fluctuations due to on-off control can be completely suppressed. For example, if the brine circulates at 10 liters / minute and the average cycle time of the operation output on-off is 20 seconds, 3.3 liters may be secured as the volume of the buffer tank.

According to the third embodiment, the size of the buffer tank 40 can be reduced to about の of the conventional volume, and the overall size of the fluid supply device can be reduced.

In the above-described embodiment, the cooler 12 is taken as an example of the heat source. However, the present invention can be applied to a case where a heater is used as the heat source according to the temperature of the fluid. In this case, for example, Expression (1) for calculating the integral value while outputting the ON signal to the cooler 12 is an expression for calculating the integral value while outputting the OFF signal to the heater. For example, Expression (2) for calculating an integral value while outputting the OFF signal to the heater 12 is an expression for calculating an integral value while outputting the ON signal to the heater.

Further, the temperature control device of the present invention is not limited to the case where the temperature of a fluid is controlled, but can be applied to the case where the temperature of a substantially fixed object in which no flow occurs is controlled. Can be widely applied to various objects that require.

Further, the two-position control device of the present invention is not limited to the case where the temperature is controlled, but can be applied to a wide range of devices that perform two-position control (on-off control) of the operation of the control target portion.

[0067]

According to the first aspect of the present invention, there is an effect that the state to be adjusted by the control target portion can be controlled with high accuracy.

According to the second aspect of the invention, the temperature of the state to be adjusted by the heat source can be controlled with high accuracy.

According to the third or fourth aspect of the present invention, it is possible to provide a fluid supply device capable of controlling the temperature of the fluid supply to the load circuit with high precision and reducing the size of the buffer tank.

According to the fifth aspect of the present invention, it is possible to provide a fluid supply device which stabilizes the outlet temperature of the fluid led out from the buffer tank and reduces the size of the buffer tank.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a fluid supply device according to a first embodiment to which a two-position control device and a temperature control device are applied.

FIG. 2 is a block diagram illustrating a configuration of a controller that controls the operation of the fluid supply device.

3A is a diagram showing a change in brine temperature when on / off control is performed, FIG. 3B is a diagram showing a change in on / off output, and FIG. 3C is a diagram showing a supply temperature; It is a figure showing change of brine supply temperature detected by a sensor.

FIG. 4 is a configuration diagram illustrating a fluid supply device according to a second embodiment.

FIG. 5 is a configuration diagram illustrating a buffer tank of a fluid supply device according to a third embodiment.

FIG. 6 (A) is a diagram showing a change in brine temperature when conventional on / off control is performed, and FIG. 6 (B) is a diagram showing a change in on / off output.

FIG. 7 is a configuration diagram showing a buffer tank in a conventional fluid supply device.

[Explanation of symbols]

10, 10a: Fluid supply device to which a two-position control device and a temperature control device are applied 11: Compressor 12: Cooler (control target portion, heat source portion) 13: Heat exchanger 14, 40: Buffer tank 16: Supply port 17: Return ports 19a to 19d Pipe (circuit for circulation) 20 Load circuit 30, 30a Controller (control unit) 31 Current temperature sensor (current temperature detection unit) 32 Supply temperature sensor 38 Flow rate sensor (flow rate detection unit) PV: brine current temperature (current value in the state adjusted by the control target unit, current temperature in the state adjusted by the heat source unit, fluid current temperature) SV: brine supply set temperature (by the control target unit) (Set value of state to be adjusted, set temperature of state to be adjusted by heat source section, set temperature of fluid) Pt: brine supply temperature F: blow Line circulation flow (circulation flow) W: Work as load

Claims (5)

[Claims] An object to be controlled (12) whose operation is on-off controlled, and a current value (P) adjusted by the object to be controlled (12)
V) and a set value (S) of a state to be adjusted by the control target unit (12).
V) and the present value (PV) are integrated, and the integrated value of the difference during the output of the ON signal to the control target unit (12), and the OFF signal to the control target unit (12). So that the integrated value of the deviation during output is constant,
And a control unit (30) for outputting an on-off signal to the control target unit (12). 2. A heat source unit (1) whose operation is on-off controlled.
2) and the current temperature (P) adjusted by the heat source section (12).
V) and a set temperature (S) to be adjusted by the heat source unit (12) and the current temperature detection unit (31).
V) and the temperature difference between the present temperature (PV) and the integral value of the difference while outputting the ON signal to the heat source section (12), and the OFF signal to the heat source section (12). A control unit (30) for outputting an on-off signal to the heat source unit (12) so that the integral value of the deviation during output is constant. . 3. A heat source unit (12) that cools or heats a circulating fluid and is turned on / off and a buffer tank (14) into which a fluid cooled or heated by the heat source unit (12) is introduced. A circuit (19) for circulating a fluid derived from the buffer tank (14) to a load circuit (20) in which a load (W) is disposed, wherein a fluid upstream from the buffer tank (14) is provided. A current temperature detector (31) disposed on the side of the side to detect a current temperature (PV) of the cooled or heated fluid; and a set temperature (S) of the fluid supplied to the load circuit (20).
V) and the temperature difference between the present temperature (PV) and the integral value of the difference while outputting the ON signal to the heat source section (12), and the OFF signal to the heat source section (12). A controller (30) for outputting an on-off signal to the heat source (12) so that the integral value of the deviation during output is constant. . 4. A heat source section (12) for cooling or heating a circulating fluid and on / off controlled, and a buffer tank (14) for introducing a fluid cooled or heated by the heat source section (12). A circuit (19) for circulating a fluid derived from the buffer tank (14) to a load circuit (20) in which a load (W) is disposed, wherein a fluid upstream from the buffer tank (14) is provided. A current temperature detector (31) that is disposed on the side and detects a current temperature (PV) of a cooled or heated fluid; and a flow detector (3) that detects a circulating flow rate (F) of the fluid.
8), and a set temperature (S) of the fluid supplied to the load circuit (20).
V) and a value obtained by integrating the circulating flow rate (F) with a temperature deviation between the current temperature (PV) and the integrated value while outputting an ON signal to the heat source unit (12); A control unit (30a) that outputs an on-off signal to the heat source unit (12) so that the integral value is constant while the off signal is output to the heat source unit (12). A fluid supply device characterized by the above-mentioned. 5. A heat source unit (12) that cools or heats a circulating fluid and is controlled on and off, and a buffer tank (40) into which a fluid cooled or heated by the heat source unit (12) is introduced. A circuit (19) for circulating a fluid derived from the buffer tank (40) to a load circuit (20) provided with a load (W), wherein the buffer tank (40) An inlet portion (44) through which fluid is introduced, an outlet portion (45) through which a fluid is led, and a rectifying means (43) having a plurality of through holes (46). A fluid supply device, wherein the fluid flowing out of the through-hole (46) is in a laminar flow state and flows toward the outlet (45).