JP3046761B2 - Environmental test equipment with non-frost operation area switching type dehumidifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an environmental test apparatus equipped with a dehumidifier and capable of non-frost operation, and more particularly to a technique for controlling a non-frost operation range.

[0002]

2. Description of the Related Art In an environmental test apparatus, it is not necessary to operate a refrigerator at a low temperature when the set temperature and humidity during operation are high. Therefore, the refrigerant evaporation pressure in an evaporator is increased to increase the evaporation temperature. Conventionally, a non-frost operation for preventing frost formation on an evaporator has been performed. In this case, whether or not to perform the non-frost operation is determined by the set value of the temperature and the humidity. The non-frost operation is performed when the set value falls within a predetermined temperature and humidity range, and the frost operation is performed at other times. Was like that.

On the other hand, in the environmental test apparatus, there is an apparatus provided with a dehumidifier in addition to an evaporator capable of cooling and dehumidifying in order to effectively perform low humidity operation. Conventionally, even in an environmental test apparatus equipped with such a dehumidifier, non-frost / frost operation is switched only in the above-mentioned constant temperature / humidity setting range regardless of whether the dehumidifier is used or not. For this reason, the conventional non-frost operation | movement corresponding to the operation state of the dehumidifier could not be performed with the conventional environmental test apparatus.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems in the prior art, and performs an appropriate non-frost operation in an environmental test apparatus equipped with a dehumidifier to improve continuous operation. The task is to provide

[0005]

According to a first aspect of the present invention, there is provided a dehumidifier, a temperature / humidity setting unit capable of setting temperature and humidity, a heater, a humidifier, and a heater.
The temperature and humidity setting section in the test chamber by controlling the
Control means for maintaining the set temperature and humidity, a refrigeration circuit including a non-frost operation means for enabling frost-free operation, a non-frost operation control means for controlling the non-frost operation means, Wherein the non-frost operation control means operates the non-frost operation means within a first range of coordinates consisting of temperature and humidity.
Control of the control means when the dehumidifier is turned off
And a second range having a lower humidity than the first range.
When the dehumidifier is turned on, it is controlled by the control means.
A second extent possible maintain Te, during dehumidifier off a determination part for inputting a set value of the temperature and humidity setting unit inputs the said dehumidifier on / off with the first and second ranges A determination portion for determining whether the input set value is within the first range and determining whether the input set value is within the first range or the second range when the dehumidifier is on; The determination unit determines that the input set value is within the first range when the dehumidifier is off or the input set value is either the first range or the second range when the dehumidifier is on. And an output part for outputting the non-frost operation means when it is determined that the non-frost operation means is operated.

According to a second aspect of the present invention, there is provided a dehumidifier capable of on / off control, a temperature / humidity setting unit capable of setting temperature and humidity, a heater, a humidifier,
The heater and humidifier are controlled to set the temperature and humidity in the test chamber.
Control means for maintaining the temperature and humidity set in the constant section and non-frost operation means for enabling frost-free operation
A dehumidifying circuit for controlling the dehumidifier and the non-frost operating means simultaneously.
Has a non-frost control means, the dehumidification / non-frost system
Control means, the first range der in coordinates consisting of a temperature and humidity
Actuating the non-frost operating means to activate the dehumidifier
Can be maintained by control of the control means when turned off
A first range and a second range having a lower humidity than the first range.
To turn on the non-frost operating means and the dehumidifier
Is maintained by the control of the control means when
A determination unit that includes a range , the first range and the second range, and inputs a set value of the temperature and humidity setting unit and determines whether the input set value falls within the first range or the second range. When the input value is determined to be within the first range by the determining portion, the dehumidifier is turned off and the non-frost operating means is output to output the signal, and the determining portion outputs And an output section for turning on the dehumidifier when the input set value is determined to be within the second range and outputting the same so as to operate the non-frost operating means. .

[0007]

FIG. 1 shows an example of the overall configuration of an environmental test apparatus to which the present invention can be applied. The environmental test apparatus includes a dehumidifier 1, a temperature and humidity setting unit 2 that can set temperature and humidity,
The refrigeration circuit 3 includes a non-frost operation unit that enables non-frosting operation, and a non-frost operation control unit 4 that is a non-frost operation control unit that controls the non-frost operation unit. As a general configuration, the environmental test apparatus has a test room 5, an air-conditioning room 6 partitioned adjacent to the test room 5, a humidifier 7, a compressor 31 constituting a refrigeration circuit 3, and an evaporator 3.
2, a heater 8, a circulation blower 9, a dry bulb temperature sensor 10, a wet bulb temperature sensor 11, and the like.

In the present embodiment, the dehumidifier 1 includes a honeycomb-shaped rotor 1a and a motor 1b for rotating the same. The rotation of the rotor 1a dehumidifies the air passing through the rotor at a 3/4 rotation of the rotor 1a. This is a type in which the dehumidifying capacity is regenerated in a quarter turn. However, in applying the present invention, it is possible to use other types of dehumidifiers. During the operation of the dehumidifier 1, a part of the air in the test chamber 5 is introduced into the dehumidifier 1 via the damper 12, and after being dehumidified, returned to the air conditioning room 6 via the damper 13 to reduce the internal low humidity environment. Is realized.

The operation of the dehumidifier 1 is performed by a human operation according to an operation manual or automatically. Automatic operation, for example, determines the dehumidifier operation zone corresponding to the set value of temperature and humidity, turns on the dehumidifier if the set temperature and humidity are in the operation zone, and turns off the dehumidifier in other cases It is done in a way that In the case of performing the manual operation or any automatic operation, the on / off signal of the dehumidifier 1 is sent to a determination unit of a non-frost operation control unit described later.

The temperature / humidity setting unit 2 includes temperature and humidity setting switches 21 and 22 and is provided together with the non-frost operation control unit 4 in the operation control panel 50 of the environmental test apparatus. The operation control panel 50 controls the temperature and humidity set by the respective switches, the detected temperature and humidity of the sensors 10 and 11, and the like.
The humidifier 6 and the heater 8 are controlled to maintain the inside of the test chamber 5 at a target temperature and humidity.

FIG. 2 shows a configuration example of the refrigeration circuit 3 and the non-frost operation control unit 4. The refrigeration circuit 3 includes the compressor 31 and the evaporator 32 also illustrated in FIG. 1, and includes a condenser 33, an expansion mechanism 34 including any one of a capillary tube and an electronic expansion valve, and a parallel as an example of a non-frost operating means. An electromagnetic valve 35 and an evaporation pressure adjusting valve 36 which constitute a circuit are provided. When the solenoid valve 35 is closed, the evaporation pressure regulating valve 36 is set such that the primary pressure corresponding to the evaporator outlet pressure becomes a pressure corresponding to about 1 to 5 ° C. at the evaporation temperature. As a result, when the electromagnetic valve 35 is closed, the evaporating temperature becomes positive, so that no frost is formed on the evaporator, and the non-frost operation is realized.

On the other hand, the solenoid valve 35 is large enough to allow a sufficient amount of refrigerant to pass therethrough. When the solenoid valve 35 is opened, the refrigerant is juxtaposed even if the evaporation pressure adjusting valve 36 is closed to increase the pressure. The pressure flows through the solenoid valve 35 with a small resistance, and the pressure in the evaporator becomes the same as the outlet pressure of the expansion mechanism 34, the temperature correspondingly decreases, and the low-temperature frost operation can be performed. The temperature at this time is, for example, −20 ° C. to −40.
° C.

The non-frost operating means may be any means capable of switching the level of the evaporation pressure or the temperature, and is not limited to the above-described parallel circuit formed by the combination of the solenoid valve and the evaporation pressure adjusting valve. For example, instead of the solenoid valve 35,
A pneumatically or hydraulically operated control valve may be used. Further, in place of the pressure regulating valve, a temperature regulating valve may be used, or in a case where the operating condition does not change so much, a constant throttle mechanism such as an orifice may be used. Furthermore, instead of a parallel circuit of the solenoid valve and the evaporating pressure adjusting valve, only an evaporating pressure adjusting valve is provided that has a small resistance when fully opened and allows a sufficient flow rate to adjust the pressure, and the pressure is adjusted in the non-frost operation, and in the frost operation, A configuration in which the setting is set to fully open is also possible.

The non-frost operation control section 4 includes a judgment section 4
1 and an output portion 42. The determination part 41 includes a first range A and a second range B having a lower humidity in coordinates made up of temperature and humidity illustrated in FIG. 2B, and inputs ON / OFF of the dehumidifier 1 and , A point P composed of a set temperature t and a set humidity H which are set values of the temperature and humidity setting unit 2
(T, H) is input. Then, it is determined whether or not the point P, which is the set value input when the dehumidifier is off, is within the first range A, and the point P is within either the first range A or the second range B when the dehumidifier is on. Determine if it is.

The output unit 42 determines whether the point P is within the first range A when the dehumidifier is off or determines that the point P is in the first range A or the second range when the dehumidifier is on. If it is determined that any one of B and B is included, an output is made to operate the solenoid valve 35 and the pressure regulating valve 36 which are non-frost operating means. That is, the operation of the pressure regulating valve 36 is made effective by closing the electromagnetic valve 35, and the evaporating pressure and the evaporating temperature are raised to enable the non-frost operation.

According to the above-described non-frost operation control, the first range A indicates the non-frost operation range when the dehumidifier is stopped, and the second range B indicates the non-frost operation which is expanded only during the dehumidifier operation. Will indicate the range. First range A
Is determined based on the relationship between the temperature and humidity that can be reached only by the evaporator 32 of the refrigeration circuit when the dehumidifier is not operated, for example, when the refrigerant temperature is 5 ° C. More specifically, it can be expressed as a straight line by the equation H = -at + b. The first range A varies depending on various conditions such as the presence or absence and size of moisture or heat load from the sample placed in the test chamber 5 and the target time for reaching the set temperature and humidity. Equations a and b are determined as appropriate in an actual environmental test apparatus.

The second range B is determined from the relationship between the temperature and the humidity that can be reached by the evaporator 32 of the refrigerator and the dehumidifier 1 when the dehumidifier is operated, for example, when the refrigerant temperature is 5 ° C. . When the low humidity condition is achieved, cooling and dehumidification by the refrigerator are not effective. Therefore, the dehumidifier 1 does not operate at a low temperature without operating the refrigerator at a low temperature even in consideration of the moisture load from the sample. It is often set so that humidity can be obtained. Therefore, in the example of the figure, when the dehumidifier is operated, the non-frost operation range is expanded to zero relative humidity as shown by the second range B. The third range C indicates a low temperature range that cannot be achieved by the non-frost operation regardless of the operation of the dehumidifier 1. It varies depending exothermic load and the like, limit temperature t ₁ of the third range C, for example 15 ° C
To the extent.

FIG. 3 shows an example of a control flow when the above-described non-frost operation control is performed. It is determined whether or not the dehumidifier is turned on (S-1). If not, the set temperature t is equal to or higher than t ₁ and the set relative humidity H is a value calculated by (at + b) in the previous equation. It is determined whether or not both conditions are satisfied (S-2) (this corresponds to a determination as to whether or not the set value falls within the first range A of FIG. 2A). The solenoid valve 35 is closed and the non-frost operation is performed (S
-3) In other cases, control is performed such that the electromagnetic valve is opened to perform the frost operation (S-4). If dehumidifier becomes ON, the determination of whether the set temperature t is determined whether t ₁ or more (S -5) (This set value is in the either the first region A or the second range B If not, control is performed such that non-frost operation is performed (S-3), and in other cases, frost operation is performed (S-4).

FIG. 4 shows another example of a device for performing a non-frost operation. In the environmental test apparatus of this example, the dehumidifier 1 can be turned on / off, and the dehumidifier 1 and the solenoid valve 35 as non-frost operating means are simultaneously controlled.
A dehumidification / non-frost operation control unit 4 'is provided as non-frost control means. The dehumidification / non-frost operation control unit 4 ′ includes a first range A and a second range in which the humidity is lower than the first range A in the coordinates composed of the temperature and the humidity shown in FIG. And a determination part 41 ′ for determining whether the set value falls within the first range A or the second range B, and it is determined that the set value input by the determination part falls within the first range A. The dehumidifier 1 is turned off and the solenoid valve 35 is closed to output the non-frost operation means. If it is determined that the input set value is within the second range B, the dehumidifier 1 is turned on. Output part 42 for outputting the solenoid valve 35 to be closed.
'.

In the environmental test apparatus shown in FIGS.
To the third ranges A to C, and the non-frost operation control unit 4
Is controlled so that the non-frost operation is performed only when the dehumidifier 1 is turned on when the set value of the temperature and the humidity is in the second range B. In this case, the dehumidifier 1 is automatically operated by manual operation or various methods, and is always turned on in a low humidity condition, but is not always operated in an intermediate humidity condition. Therefore, depending on the operation method of the dehumidifier 1, there is a possibility that the dehumidifier is not operated under the temperature and humidity conditions on the lower humidity side than the boundary L between the first and second ranges. In such a case, a region where the frost operation must be performed in the second range B occurs, and it becomes impossible to partially secure continuous operation.

On the other hand, in the apparatus shown in FIG. 4, the dehumidifier 1 can be controlled to be turned on / off, and in the second range B, the dehumidifier 1 is controlled so as to be actively turned on. In addition, the non-frost operation can be reliably performed in the entire first and second ranges A and B except the third range of the low temperature condition where the frost operation is essential, and the continuous operation of the environmental test apparatus can be improved.

By turning on the dehumidifier 1,
Dehumidification may be excessive near the boundary line L, and the amount of rehumidification by the humidifier may increase. However, by increasing the capacity of the dehumidifier, the increase in the capacity of the humidifier 7 can be suppressed. it can. However, since the non-frost operation is also performed in the second range B in the apparatus of the present example, the dehumidifying capacity of the evaporator 32 is greatly reduced as compared with the conventional case where the frost operation is performed. The excess dehumidification associated with is reduced. Further, a plurality of dehumidifiers 1 may be provided or the dehumidification capacity may be controlled so that the number of operating dehumidifiers is minimized or the dehumidification capacity is controlled to be small on the low humidity side near the boundary line L. By doing so, the problem of excessive dehumidification is completely eliminated.

[0023]

According to the present invention, according to the first aspect of the present invention, the non-frost operation control means having the determining portion and the output portion is configured such that when the dehumidifier is off, the temperature and humidity inputted when the dehumidifier is off by the determining portion. When it is determined that the set value falls within the first range in the temperature and humidity coordinates, the non-frost operating means is operated. When the dehumidifier is on, the set value falls within the second range having a lower humidity than the first range. When the dehumidifier is turned on, the non-frost operation means is operated, so that the non-frost operation range when the dehumidifier is on can be expanded.

By the way, according to the non-frost operating means, the refrigerant evaporating temperature in the evaporator is increased. Therefore, when the non-frost operating means is operated, the low temperature condition cannot be realized and the dew point temperature of the air can be reduced even under the high temperature condition. Under low humidity conditions, the air cannot be cooled to the dew point temperature or lower and liquefied and dehumidified, so that low humidity conditions cannot be realized. Therefore, as described above, the non-frost operation range is limited to the first range on the high humidity side.

On the other hand, a dehumidifier is provided in an environmental test apparatus having low-humidity operating conditions to assist dehumidification by an evaporator. It also has the effect of avoiding anti-energy-saving operation of reheating by a heater. Therefore, during the operation of the dehumidifier, even if the refrigerant evaporation temperature in the evaporator is increased and the dehumidification capability of the evaporator is reduced, the desired low humidity condition is achieved by the dehumidification capability of the dehumidifier. As a result, during the operation of the dehumidifier, the non-frost operation in the second range where the humidity is lower than the first range becomes possible.

As described above, according to the first aspect of the present invention,
By reasonably combining the characteristics of the non-frost operating means, the operation and effect of the dehumidifier, and the installation purpose thereof, the non-frost operation can be performed up to the second range in addition to the first range during the dehumidifier operation. In a wide range, continuity of control and operation in the environmental test device can be ensured by avoiding defrosting operation with interruption of steady operation.

According to the second aspect of the present invention, a dehumidification / non-frost control means is provided, and the second dehumidification / non-frost control means having a lower humidity than the first range.
In the range, since the dehumidifier is positively turned on and the non-frost operation can be performed, the non-frost operation can be always performed in both the first range and the second range, and the first and second ranges can be performed.
The continuous operation of the environmental test device can be more reliably ensured in the entire range.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing the overall configuration of an environmental test apparatus to which the present invention is applied.

FIG. 2A is an explanatory diagram showing a configuration of a refrigeration circuit and a non-frost operation control unit of the environmental test apparatus, and FIG. 2B is an explanatory diagram of a non-frost operation range.

FIG. 3 is a flowchart illustrating an example of a non-frost operation control method.

FIG. 4 is an explanatory diagram showing a configuration of a refrigeration circuit and a dehumidification / non-frost operation control unit in another example of the environmental test apparatus to which the present invention is applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Dehumidifier 2 Temperature / humidity setting part 4 Non-frost operation control part 4 'Dehumidification / non-frost operation control part (dehumidification / non-frost control means) 35 Solenoid valve (non-frost operation means) 36 Evaporation pressure regulating valve (non-frost operation means) ) 41, 41 'judgment part 42, 42' output part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F25B 47/02 F24F 11/02 F25B 1/00

Claims (2)

(57) [Claims] 1. A dehumidifier, a temperature / humidity setting unit capable of setting temperature and humidity, a heater, a humidifier, the heater and the heater.
The humidity chamber was controlled and the test chamber was set by the temperature and humidity setting unit.
An environmental test apparatus comprising: a control unit for maintaining the temperature and the humidity; a refrigeration circuit including a non-frost operation unit which enables a non-frosting operation; and a non-frost operation control unit for controlling the non-frost operation unit. In the non-frost operation control means, the non-frost operation control means may be a first range in coordinates consisting of temperature and humidity.
Operating the dehumidifier to turn off the dehumidifier
And a second range having a lower humidity than the first range and the non-frost operating means.
And controlling the control means when the dehumidifier is turned on.
A second range that can be maintained by the first range and the second range.
A determination section for inputting ON / OFF of the dehumidifier having a range and inputting a set value of the temperature / humidity setting section, and determines whether or not the set value input when the dehumidifier is OFF falls within the first range; And a judgment part for judging whether or not the set value inputted when the dehumidifier is on is included in any of the first range and the second range, and the set value inputted when the dehumidifier is off by the judgment part. When it is determined that the set value is within the first range or when the input set value is determined to be within either the first range or the second range when the dehumidifier is on, the non-frost operating means is activated. And an output part for outputting an operation. 2. A dehumidifier capable of on / off control, a temperature / humidity setting unit capable of setting temperature and humidity, a heater, and a humidifier.
, A heater and a humidifier to control the test chamber
Control means to maintain the temperature and humidity set in the temperature and humidity setting section
Steps and non-frost operating means to enable frost-free operation
An refrigeration circuit comprising: a dehumidifier / non-frost control means for simultaneously controlling the dehumidifier and the non-frost operating means; wherein the dehumidification / non-frost control means comprises a temperature and a humidity. A first range in coordinates consisting of:
Operating the dehumidifier to turn off the dehumidifier
And a second range having a lower humidity than the first range and the non-frost operating means.
And controlling the control means when the dehumidifier is turned on.
A second range that can be maintained by the first range and the second range.
A judging part having a range, inputting a set value of the temperature / humidity setting unit, and judging whether the inputted set value falls within the first range or the second range, and the setting inputted by the judging part When it is determined that the value is within the first range, the dehumidifier is turned off and the non-frost operating means is output so as to be activated, and the set value input by the determination portion falls within the second range. An output portion for outputting the signal to turn on the dehumidifier and to operate the non-frost operating means when it is determined that the dehumidifier is on.