JP4505486B2 - Heat pump air conditioner - Google Patents

Description

  The present invention relates to a heat pump type air conditioner.

  In air conditioning in special environments such as electronic factories, agricultural factories, breeding rooms, and grain warehouses, it is necessary to adjust the temperature and humidity by heating and cooling the air-conditioning air in a predetermined order and appropriately humidifying it. Therefore, for example, there is a system in which a cold water coil (cooling coil), a hot water coil (heating coil), a humidifier, and the like are provided, and the heat source water circuit is a four-pipe type, and the cold water and the hot water coil are separately supplied with cold water and hot water. However, the four-pipe heat source water circuit has a problem that the piping distance is long and the equipment cost is high, and it is necessary to make cold water and hot water at the same time.

  In addition, since the heat pump has an upper limit on the air heating temperature (refrigerant condensation temperature), the vaporization method is used under conditions where the air temperature / humidity is low and a large amount of humidification is required with respect to the desired temperature and humidity (especially high temperature and humidity) When humidified, the desired supply air temperature may not be reached due to latent heat of vaporization. Therefore, there is a problem that the temperature / humidity range in which air conditioning can be performed becomes narrow, and the compression efficiency and consequently the coefficient of performance (COP) decrease. In cold and hot areas, air conditioning air such as outside air may be preheated or precooled, but a heater or a cooler such as a cold / hot water coil is required separately from the air conditioner. Further, when an air-cooled heat pump is used, increasing the capacity by increasing the number of evaporators requires a large blower on the condenser side, resulting in a problem of operating costs.

JP-A-63-233244

  The problem to be solved is that the equipment cost and the operating cost become high, and a heat pump type air conditioner that can be widely applied to air conditioning in various special environments, is compact, and has good COP.

  In order to solve the above-mentioned problems, the present invention provides first, second and third compression heat pumps, a blower for supplying air for air conditioning to an air-conditioned space, and a condensing blower for blowing heat exchange air. A first evaporator for refrigerant-air heat exchange of the first heat pump, a second evaporator for refrigerant-air heat exchange of the second heat pump, and the second evaporator. A refrigerant-air heat exchange third evaporator of a three heat pump is arranged in the order of the first evaporator, the second evaporator, and the third evaporator in the air blowing direction of the air-conditioning air. A refrigerant-air heat exchange second condenser of the third heat pump that exchanges heat of the circulating refrigerant with exchange air, and a refrigerant-air heat exchange first condenser that is shared by the first and second heat pumps, The second condenser and the first condensation in the direction of blowing the heat exchange air Are arranged in the order of two locations, between the first evaporator and the second evaporator, between the second evaporator and the third evaporator, and leeward of the third evaporator. Alternatively, humidifiers are provided at all locations, and heat absorption and heat dissipation of the circulating refrigerant by the first evaporator and the first condenser of the first heat pump are performed, and the second evaporator and the first heat pump of the second heat pump are performed. The main feature is that the heat absorption and heat release of the circulating refrigerant by the condenser and the heat absorption and heat release of the circulation refrigerant by the third evaporator and the second condenser of the third heat pump are respectively switchable. And

According to the invention of claim 1,
(1) Air conditioning operation in a special environment can be performed only with a heat pump without using a four-pipe cold / hot water coil.
(2) Since humidifiers are arranged at two or three locations, heating and humidification can be performed in multiple stages, the temperature / humidity range (especially the high temperature and high humidity side) where air conditioning can be expanded, compression efficiency and COP Will be better.
(3) Since air conditioning operation is performed with the first and second heat pumps and precooling and preheating can be performed with the third heat pump, the temperature and humidity control range is widened. Separate pre-cooling and pre-heating equipment is not required.
(4) When one of the first and second condensers is condensed and the other is evaporated as in the dehumidifying and drying air-conditioning operation, the circulating refrigerant is exchanged between the first and second condensers via heat exchange air. Heat exchange can be performed and less blasting power is required, so that the size and energy saving of the blower can be achieved. For example, in a dehumidifying and drying operation in which air for air conditioning is cooled and dehumidified by a first evaporator and a second evaporator and then heated by a third evaporator, the heat exchange air cooled by the second condenser is used for the first. Since the refrigerant condensation of one condenser is performed, the condensation temperature is lowered, the refrigeration capacity of the first evaporator and the second evaporator is increased, and the compression power of the first heat pump and the second heat pump is reduced and the COP is improved.
According to the invention of claim 2,
(1) When air-conditioning air is heated by the first and second evaporators, the first and second heat pumps are operated even under conditions of heat exchange air that causes frost formation in the first condenser. Without stopping, the condenser defrosting circuit can prevent frosting of the first condenser and can perform comfortable air conditioning.
(2) Since the refrigerant circulation to the third evaporator is stopped and the hot gas is circulated only in the second condenser for defrosting, the defrosting capability is high and defrosting can be performed in a short time, and the stability of temperature and humidity control Excellent.
According to the invention of claim 3,
(1) Since the pressure loss is reduced and the heat exchange efficiency is improved, a small blower can be used and noise can be reduced. The first, second, and third evaporators, and the first and second condensers can be reduced in size, and the air conditioner can be reduced in size.

  1 and 2 show an embodiment of the heat pump type air conditioner of the present invention, and the solid and dotted white arrows indicate the blowing direction. This air conditioner receives air supply air passage 9, first, second, and third compression heat pumps A, B, and C, humidifiers 5 and 5, and air-conditioning air in casing 1. A blower 6 for supplying air to the space, a blower path 8, and a condenser blower 7 for blowing heat exchange air such as outside air, return air or mixed air thereof, and heat exchange of air-conditioning air with a circulating refrigerant The first evaporator 2a for refrigerant-air heat exchange of the first heat pump A, the second evaporator 2b for refrigerant-air heat exchange of the second heat pump B, and the third evaporator for refrigerant-air heat exchange of the third heat pump C 2c are arranged in the order of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c in the air-conditioning air blowing direction, and heat exchange air is used to exchange heat with the circulating refrigerant. 3 heat pump C refrigerant-air heat exchange second condenser 3c and first and second heat pumps A, The common refrigerant-air heat exchange first condenser 3a is arranged in the order of the second condenser 3c and the first condenser 3a in the air exchange direction of the heat exchange air, and the second evaporator 2b and the first condenser 3a are arranged in this order. The humidifier 5 is disposed both between the three evaporators 2c and leeward of the third evaporator 2c, and the heat absorption and heat dissipation of the circulating refrigerant by the first evaporator 2a and the first condenser 3a of the first heat pump A are performed. The heat absorption and heat dissipation of the circulating refrigerant by the second evaporator 2b and the first condenser 3a of the second heat pump B, and the heat absorption of the circulating refrigerant by the third evaporator 2c and the second condenser 3c of the third heat pump C And heat dissipation are configured to be switchable.

  The evaporators 2a, 2b, 2c of the first, second, and third heat pumps A, B, and C are configured to be capable of switching between refrigerant evaporation and refrigerant condensation. For example, the first evaporator 2a and the second evaporator 2b The refrigerant is evaporated in one or two or all of the third evaporators 2c and / or the refrigerant is evaporated in both or one of the first evaporator 2a and the second evaporator 2b and condensed in the third evaporator 2c. A cycle in which the refrigerant is evaporated in the cycle and the first evaporator 2a and the refrigerant is condensed in the second evaporator 2b and / or the third evaporator 2c, and the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c can be switched at least to the cycle in which the refrigerant is condensed in one, two or all of the refrigerants, or the refrigerant is evaporated in both or one of the first evaporator 2a and the second evaporator 2b and in the third evaporator 2c. Refrigerant condensation cycle and first steam A cycle of refrigerant evaporation in the evaporator 2a and refrigerant condensation in both or one of the second evaporator 2b and the third evaporator 2c, one of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c or A cycle in which refrigerant is condensed at least in two or all, or a cycle in which refrigerant is evaporated in one, two, or all of the first evaporator 2a, the second evaporator 2b and the third evaporator 2c A cycle in which the refrigerant is condensed in both or one of the first evaporator 2a and the second evaporator 2b and the refrigerant is evaporated in the third evaporator 2c, the refrigerant is condensed in the first evaporator 2a, and the second evaporator 2b and the third evaporator It is configured to be switchable at least to a cycle for evaporating the refrigerant in both or one of the evaporators 2c.

  The first condenser 3a and the second condenser 3c of the third heat pump C are refrigerant-air heat exchangers, and at least the third heat pump C is provided with a hot gas type condenser defrosting circuit G. The refrigerant flow passage of the first heat pump A and the refrigerant flow passage of the second heat pump B in the first condenser 3a are arranged so as to be able to exchange heat with each other. In the first condenser 3a, the refrigerant of the first heat pump A and the second The heat pump B is configured such that one of the refrigerants of the heat pump B evaporates and the other is condensed, and the two different refrigerants circulate in an opposing manner to achieve uniform and efficient heat transfer by the counter flow. Further, the first condenser 3a is configured so that the flowing refrigerant is different for each row of fin tubes, for each stage of fin tubes, or for each fin tube, thereby eliminating uneven heat exchange with air and stabilizing the performance. . The first heat pump A includes a common first condenser 3a for exchanging heat of the circulating refrigerant with heat exchange air, a first evaporator 2a for exchanging heat of air-conditioning air with the circulation refrigerant, and a first compressor. 4a, an expansion valve, a forward / reverse switching valve (four-way valve) in the refrigerant circulation direction, a liquid receiver (not shown), etc., which are connected by piping to form a refrigerant circulation circuit and The heat absorption and heat release (evaporation function and condensation function) of the first condenser 3a and the first evaporator 2a are configured to be switchable. The second heat pump B includes a common first condenser 3a, a second evaporator 2b for exchanging heat of air-conditioning air using a circulating refrigerant, a second compressor 4b, an expansion valve, and a positive refrigerant circulation direction. A reverse switching valve (four-way valve), a liquid receiver (not shown) and the like are provided, and these are connected by piping to form a refrigerant circulation circuit, and the first condenser 3a and the second evaporator 2b are connected by the switching valve. The heat absorption and heat dissipation (evaporation function and condensation function) can be switched. The third heat pump C includes a second condenser 3c that exchanges heat of the circulating refrigerant using heat exchange air, a third evaporator 2c that exchanges heat of the air-conditioning air using circulation refrigerant, a compressor 4c, and an expansion valve. And a switching valve (four-way valve) for forward and reverse of the refrigerant circulation direction, a liquid receiver (not shown), etc., which are connected by piping to form a refrigerant circulation circuit, and the second condenser 3c is constituted by the switching valve. The heat absorption and heat release (evaporation function and condensation function) of the third evaporator 2c are configured to be switchable. The third heat pump C includes a condenser defrost circuit G that stops the refrigerant circulation to the third evaporator 2c by the three-way valve 10 and circulates the hot gas of the compressor 4c only in the second condenser 3c to defrost. Although it is provided, it is also free to provide this condenser defrost circuit G in the other heat pumps A and B. The humidifier 5 can be of various types such as a vaporization method and a steam blowing method. However, if the steam blowing method is used, the temperature and humidity control can be performed with high accuracy and the temperature and humidity can be controlled without any temperature drop. The load on the vessel can be reduced.

  The air-conditioning air inlet and air-conditioning air outlet of the air supply air passage 9 are provided in the casing 1, and the air-conditioning air inlet is used for intake of return air, intake of outside air or mixed air intake of return air and outside air, etc. The air-conditioning air outlet is communicated with the air-conditioned space such as the room via the duct and the air-conditioned air outlet is communicated with the air-conditioned space such as the room via the duct. An air inlet for heat exchange and an air outlet for heat exchange in the air passage 8 are provided in the casing 1, and the air inlet for heat exchange is a duct for intake of return air, intake of outside air, or intake of mixed air of return air and outside air. The air outlet for heat exchange is communicated with an air-conditioned space such as a room or the outside via a duct, and the air outlet for heat exchange is communicated with the outside via a duct for exhaust. The air supply air passage 9 and the air supply passage 8 are arranged in parallel so that the air blowing directions are opposite to each other, and the air conditioning air outlet of the air supply air passage 9 and the heat exchange air inlet of the air passage 8 are on the same surface side. Make it easy to do duct construction. While air is blown to the second condenser 3c and the first condenser 3a, and air is blown by the blower 6, the air for air conditioning is exchanged in the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c ( Cooled and heated) to supply air to the air-conditioned space and perform air-conditioning operation according to various environments. The fin tubes of the first evaporator 2a, the second evaporator 2b, the third evaporator 2c, the first condenser 3a, and the second condenser 3c are preferably elliptical tubes with little pressure loss, but may be circular tubes.

  The illustrated air conditioner controls the capacity of the first, second, and third heat pumps A, B, and C, the blowers 6 and 7, the upwind and leeward humidifiers 5 and 5, and supplies air. Control means (not shown) for switching between refrigerant evaporation and refrigerant condensation among the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c according to the road inlet air temperature and humidity is provided. In order to perform the outside air processing of the air-conditioned space, for example, when the air supply / airway inlet air temperature / humidity is higher than the desired air supply / humidity, the first evaporator 2a, the second evaporator 2b, and the third evaporator Cooling and dehumidifying in one, two or all of 2c, or cooling and dehumidifying in first evaporator 2a and then heating in both or one of second evaporator 2b and third evaporator 2c Temperature control or cooling and dehumidification in both or one of the first evaporator 2a and the second evaporator 2b and then heating and temperature adjustment in the third evaporator 2c to control to a predetermined temperature and humidity . When the temperature of the supply air supply passage inlet air is low and the humidity is high with respect to the desired air supply humidity, both the second evaporator 2b and the third evaporator 2c are cooled and dehumidified by the first evaporator 2a. Alternatively, the temperature is controlled by heating at one side, or the temperature is controlled by dehumidifying by cooling at both or one side of the first evaporator 2a and the second evaporator 2b and then heated by the third evaporator 2c, and the predetermined temperature Control the supply air temperature and humidity. When the air supply / airway inlet air temperature / humidity is lower than the desired air supply / humidity, the air is heated by both or one of the first evaporator 2a and the second evaporator 2b and then humidified by the windward humidifier 5 Furthermore, after heating by the 3rd evaporator 2c, it humidifies by the leeward side humidifier 5, and is controlled to predetermined supply air temperature humidity. In this case, one, two, or all of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c are used according to the heating amount and the humidification amount necessary to obtain a desired temperature and humidity. It can also be heated and humidified by only one of the windward side humidifier 5 and the leeward side humidifier 5 to control to a predetermined temperature and humidity. When the temperature of the inlet air passage is high and the humidity is low with respect to the desired temperature and humidity, one, two, or all of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c are used. It dries and cools, humidifies in both or one of the windward side humidifier 5 and the leeward side humidifier 5, and it controls to predetermined air supply humidity. The control means also performs condenser surface wind speed control by the blower 7 in accordance with the condenser load. For example, when the condenser load increases, the condenser surface wind speed increases, and when the condenser load decreases, the condenser surface wind speed decreases. By setting the surface wind speed of the condenser 3 to 4.0 to 6.0 m / s, the amount of heat can be secured above the compressor performance limit, and the COP is improved. By exchanging heat with the condenser at high wind speeds in this way, COP can be improved and energy can be saved, and a compact condenser can be used to make the air conditioner compact. Capability can be adjusted, and it can be used in a wide range of areas from cold to hot without increasing the size of the compressor.

  In order to air-condition the air-conditioned space at a constant temperature and humidity, for example, when the leeward side humidifier 5 is a steam blowing system, the air supply / airway inlet air temperature / humidity is set to a desired air supply / humidity. When the temperature is high and when the temperature of the inlet air of the supply air passage is low and the humidity is high with respect to the desired temperature and humidity, the second evaporator 2b and the third evaporator are cooled and dehumidified by the first evaporator 2a. Heat control in both or one of 2c, or temperature control by cooling and dehumidifying in both or one of first evaporator 2a and second evaporator 2b, and then heating in third evaporator 2c Alternatively, after cooling and dehumidifying in the first evaporator 2a, the temperature is adjusted by heating in both or one of the second evaporator 2b and the third evaporator 2c and then the temperature is controlled by steam in the leeward humidifier 5 Humidification without lowering the temperature, or cooling and dehumidification in both or one of the first evaporator 2a and the second evaporator 2b, and then the third Humidified without lowering the temperature by the steam at the leeward side humidifier 5 After temperature control by heating at Hatsuki 2c, is controlled to a predetermined supply air humidity. When the air supply / airway inlet air temperature / humidity is lower than the desired air supply / humidity, heating is performed by one, two, or all of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c. After the temperature is adjusted, the air is humidified without lowering the temperature by steam in the leeward humidifier 5 and controlled to a predetermined temperature and humidity. In this case, after heating by the 1st evaporator 2a or the 2nd evaporator 2b, it humidifies by the windward side humidifier 5, Furthermore, after heating by the 3rd evaporator 2c, in the leeward side humidifier 5 Humidification can be performed without lowering the temperature with steam, and control to a predetermined temperature and humidity can be performed. When the temperature of the inlet air passage is high and the humidity is low with respect to the desired temperature and humidity, one, two, or all of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c are used. After drying and cooling and adjusting the temperature, the leeward humidifier 5 is humidified without lowering the temperature by steam and controlled to a predetermined temperature and humidity.

  In this case, the air-conditioned space can be dehumidified and dried without stopping the humidifiers 5 and 5 on the windward and leeward sides. For example, when the air supply / airway inlet air temperature / humidity is higher than the desired air temperature / humidity, and when the air supply / airway inlet air temperature is lower and the humidity is higher than the desired air temperature / humidity, the first evaporator 2a. And the second evaporator 2b is cooled and dehumidified and then heated by the third evaporator 2c, or cooled and dehumidified by the first evaporator 2a and then the second evaporator 2b and the third evaporator 2b. It heats in both or one of the evaporators 2c, and controls to predetermined supply air temperature humidity. When the air supply / airway inlet air temperature / humidity is lower than the desired air supply / humidity, heat is performed by one, two, or all of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c, Control to a predetermined temperature and humidity.

  In order to humidify the air-conditioned space at a low temperature, for example, when the air supply / airway inlet air temperature / humidity is higher than the desired air supply / humidity, the first evaporator 2a, the second evaporator 2b, and the third evaporator Cooling and dehumidification are performed in one, two, or all of 2c, and control is performed to a predetermined temperature and humidity. When the air temperature at the inlet of the supply air passage is lower than the desired air temperature and humidity, the air is heated by both or one of the first evaporator 2a and the second evaporator 2b and then humidified by the windward humidifier 5. After that, it is dried and cooled by the third evaporator 2c and controlled to a predetermined temperature and humidity. When the temperature of the supply air supply passage inlet air is high and the humidity is low with respect to the desired supply air temperature and humidity, the air is humidified by the windward side humidifier 5 and then either or both of the second evaporator 2b and the third evaporator 2c. Dry, cool, and control to a predetermined temperature and humidity. Further, in each of the above air conditioning examples, when one or both of the first evaporator 2a and the second evaporator 2b are heated and frost formation occurs in the first condenser 3a, the refrigerant to the third evaporator 2c The circulation is stopped, the hot gas is circulated only in the second condenser 3c, and the first condensation is performed by the air heated by the second condenser 3c without stopping the operation of the first and second heat pumps A and B. The device 3a can be defrosted. In addition, although illustration is omitted, the humidifier 5 is between the first evaporator 2a and the second evaporator 2b, between the second evaporator 2b and the third evaporator 2c, leeward of the third evaporator 2c, Of these, it is free to arrange at one or two or all of the locations. If all locations are provided, heating / humidification can be performed in three stages, and the temperature and humidity control range is further expanded.

  The present invention is not limited to the above-described embodiment, and can be freely changed in design without departing from the gist of the present invention. For example, the first, second, and third heat pumps A, B, C and the configuration of the control means The cycle of refrigerant evaporation and refrigerant condensation of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c can be freely changed and increased / decreased.

The front view which shows the Example of a heat pump type air conditioner. The simplified explanatory drawing of a heat pump.

Explanation of symbols

2a 1st evaporator 2b 2nd evaporator 2c 3rd evaporator 3a 1st condenser 3c 2nd condenser 5 humidifier A 1st heat pump B 2nd heat pump C 3rd heat pump

Claims (3)

  First, second, and third compression heat pumps A, B, and C, a blower 6 that supplies air for air conditioning to an air-conditioned space, and a condensing blower 7 that blows air for heat exchange are provided. The first evaporator 2a for the refrigerant-air heat exchange of the first heat pump A, the second evaporator 2b for the refrigerant-air heat exchange of the second heat pump B, and the second evaporator for exchanging heat of the air-conditioning air with the circulating refrigerant. The third evaporator 2c for refrigerant-air heat exchange of the 3 heat pump C is arranged in the order of the first evaporator 2a, the second evaporator 2b, and the third evaporator 2c in the air blowing direction of the air conditioning air. The third heat pump C refrigerant-air heat exchange second condenser 3c and the first and second heat pumps A, B common refrigerant-air that are installed and exchange heat of the circulating refrigerant with heat exchange air. The first condenser 3a for heat exchange is moved forward in the air blowing direction of the heat exchange air. The second condenser 3c and the first condenser 3a are arranged in this order, and between the first evaporator 2a and the second evaporator 2b, the second evaporator 2b and the third evaporator 2c, During this time, humidifiers 5 are disposed at two or all of the lee of the third evaporator 2c, and circulated by the first evaporator 2a and the first condenser 3a of the first heat pump A. The heat absorption and heat dissipation of the refrigerant, the heat absorption and heat dissipation of the circulating refrigerant by the second evaporator 2b and the first condenser 3a of the second heat pump B, and the third evaporator 2c of the third heat pump C A heat pump air conditioner characterized in that the heat absorption and heat release of the circulating refrigerant by the second condenser 3c are switchable.   At least the third heat pump C is condensed by defrosting by circulating the hot gas of the compressor 4c of the third heat pump C only to the second condenser 3c by stopping the refrigerant circulation to the third evaporator 2c by the three-way valve 10. The heat pump type air conditioner according to claim 1, wherein a defroster circuit G is provided.   The heat pump air conditioner according to claim 1 or 2, wherein the fin tubes of the first, second and third evaporators 2a, 2b and 2c and the fin tubes of the first and second condensers 3c are elliptical tubes.

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