REVERSIBLE DEVICE FOR THE PRODUCTION OF HOT AND COLD AIR

Abstract

A reversible heat pump device (100) is described by means of an appropriate direction of air flows, with R744 refrigerant (natural gas, non-toxic, non-flammable, readily available), for the production of hot and cold air; the device object of the present invention is composed of a suction damper system (1) consisting of concentric cylinders (A, B, C), designed to implement the reversibility of the operation between heating and cooling), and a refrigeration circuit comprising: cold exchanger (2) and a hot exchanger (3), located between the intake damper system (1) and the delivery damper system (4) consisting of concentric cylinders (D, E, F), also designed to implement the reversibility of operation in a manner consistent with the system of intake dampers (1).

Claims

1. Reversible heat pump device (100) by means of appropriate direction of air flows, with R744 refrigerant for the production of hot and cold air, including: a system of intake dampers (1) consisting of concentric cylinders (A, B, C), equipped with suitable openings and designed to implement the reversibility of the operation between heating and cooling; a refrigeration circuit comprising a cold exchanger (2) and a hot exchanger (3) located between the suction damper system (1) and the delivery damper system (4); a delivery damper system (4) consisting of concentric cylinders (D, E, F) equipped with suitable openings and designed to implement the reversibility of operation between heating and cooling in a manner consistent with the suction damper system (1).

2. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that: said cylinders (A, B, C) of said intake damper system (1) are equipped with suitable openings in the shell, the cylinder (B) is provided with a keyed septum (B), said cylinders (A, B, C) and said keyed septum (B) connected to the shaft (L) and provided at the ends of means for the reduction of friction (M) and to allow rotation (N).

3. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that: said cylinders (A, B, C) of said intake damper system (1), said keyed septum (B), said shaft (L) and said means for friction reduction (M) and to allow rotation (N) are connected to a plenum (O) provided with openings both on the side (P) in correspondence with the channels of external air and internal air, both on the side (Q) in correspondence with the cold exchanger (2) and the hot one (3), and said plenum (O) is equipped with air sealing systems (10) between the cylinders and the air passage opening (11) in correspondence with said openings (P, Q), and between the inner cylinder and the intermediate cylinder (12) and between the intermediate cylinder and the outer cylinder (13).

4. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that: said cylinders (D, E, F), of said delivery damper system (4) are equipped with openings in the casing, the cylinder (E) is provided with a keyed septum (E), said cylinders (D, E, F) and said keyed septum (E) connected to the shaft (R), provided at the ends of means for reduction of friction (V) and to allow rotation (Z).

5. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that: said cylinders (D, E, F) of said delivery damper system (4), said keyed septum (E), said shaft (R) and said means for friction reduction (V) and to allow rotation (Z) are connected to a plenum (T) provided with openings both on the side (U) in correspondence with the channels of external air and ambient air, which on the side (S) in correspondence with the cold (2) and hot (3) exchanger, and said plenum (T) is equipped with air sealing systems (14) between the cylinders and the opening of the air passage (15) in correspondence with said openings (S, U), and between the inner cylinder and the intermediate cylinder (16) and between the intermediate cylinder and the outer cylinder (17).

6. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that: said cold (2) and hot (3) exchangers forming part of the refrigeration circuit are connected to said suction dampers (1) and to said delivery dampers (4) by means of aeraulic ducts which integrate the respective fans (18, 19) for air movement.

7. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that: four distinct operating modes are possible, such as cooling, heating and two different ones for defrosting.

8. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that: in the cooling mode the flow of air directed to the user is diverted inside the cold exchanger (2) while the air flow from the outside is diverted to the inside of the hot exchanger (3), and said septum keyed (B) of the cylinders of the intake dampers diverts the flow of air in the direction of the cold exchanger (2).

9. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that: in the first variant of defrosting, air is taken from the external environment, the cylinders (A), (B) and (C) rotate with respect to the cooling position, the cylinders (D) and (E) remain stationary, the cylinder (F) rotates with respect to the cooling position, and the air flow coming from the outside is diverted towards the hot exchanger (3) and subsequently towards the cold exchanger (2); in the second variant of defrosting air is not taken from the external environment, the cylinders (A, B, D, E) are in the position of the heating mode, the cylinders (C) and (F) rotate with respect to the position of heating, and the air flow is diverted to the hot exchanger (3) and then to the cold exchanger (2).

10. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that it is designed for installation in small spaces, and in which, in the cooling configuration, the device (100) comprises: a damper (44) for diverting the flow of air (47) coming from an air-conditioned environment towards a cold exchanger (45); a fan unit to suck the air flow (47) and divert it through the damper (42) into a delivery channel (40) towards the air-conditioned environment; a damper (44) to divert the flow of air (39) coming from the outside to a hot exchanger (46) and then expel it (41) into the external environment by means of a damper (43).

11. Reversible device (100) for the production of hot and cold air according to claim 1, characterized in that it is designed for installation in small spaces, and in which, in the heating configuration, the device (100) comprises: a damper (44) for diverting the flow of air (47) coming from an air-conditioned environment towards the hot exchanger (46); a fan unit to suck the air flow (47) and divert it through the damper (43) into a delivery channel (41) towards the air-conditioned environment; a damper (44) to divert the flow of air (39) coming from the outside to a cold exchanger (45) and then expel it (40) into the external environment by means of a damper (42).

Description

[0040] The present invention will be better described by some preferred embodiments, provided by way of non-limiting example, with reference to the attached drawings, in which:

[0041] FIG. 1 shows an exemplary drawing of the reversible device (100) for the production of hot and cold air, according to the present invention;

[0042] FIG. 2 shows the general operating diagram of the reversible CO2 refrigeration circuit by means of a suitable system of cylindrical shutters according to the present invention;

[0043] FIG. 3 shows an exemplary drawing of the air sealing systems of the plenum (O) of the device (100) according to the present invention;

[0044] FIG. 4 shows an exemplary drawing of the air sealing systems of the plenum (T) of the device (100) according to the present invention;

[0045] FIG. 5 shows an exemplary drawing of the means for reducing friction and for rotating the shaft (L) of the device (100) according to the present invention;

[0046] FIG. 6 shows an exemplary drawing of the means for reducing friction and for rotating the shaft (R) of the device (100) according to the present invention;

[0047] FIG. 7 shows an exemplary drawing of the suction damper system of the device (100) according to the present invention;

[0048] FIG. 8 shows an exemplary drawing of the delivery damper system of the device (100) according to the present invention;

[0049] FIG. 9 shows the functional diagram of the device (100) in cooling mode according to the present invention;

[0050] FIG. 10 shows an exemplary drawing of the configuration of the cylinders of the suction and delivery dampers of the device (100) in cooling mode according to the present invention;

[0051] FIG. 11 shows the functional diagram of the device (100) in heating mode according to the present invention;

[0052] FIG. 12 shows an exemplary drawing of the configuration of the cylinders of the suction and delivery dampers of the device (100) in heating mode according to the present invention;

[0053] FIG. 13 shows the functional diagram of the device (100) in the first variant of defrosting according to the present invention;

[0054] FIG. 14 shows an exemplary drawing of the configuration of the cylinders of the suction and delivery dampers of the device (100) in the first variant of defrost according to the present invention;

[0055] FIG. 15 shows the functional diagram of the device (100) in the second variant of defrosting according to the present invention;

[0056] FIG. 16 shows an exemplary drawing of the configuration of the cylinders of the suction and delivery dampers of the device (100) in the second variant of defrosting according to the present invention;

[0057] FIG. 17 shows an exemplary drawing of a possible configuration in heating (A) and in cooling (B) in the inversion of the cycle of the air/air units of the device (100) according to the present invention;

[0058] FIG. 18 shows an exemplary drawing of the actuators present in the shafts of the cylinders and in the plenums of the device (100) according to the present invention;

[0059] FIG. 19 shows an exemplary drawing of the implementable aeraulic ducts of the device (100) according to the present invention;

[0060] FIG. 20 shows a variant of the exemplary drawing of the aeraulic ducts that can be implemented of the device (100) according to the present invention; and

[0061] FIGS. 21 and 22 show a further variant of the device according to the present invention.

[0062] The reversible device (100) for the production of hot and cold air has as its refrigerant the natural refrigerant gas R744, carbon dioxide CO2, non-toxic and non-flammable and is based on a system of rotating cylindrical shutters.

[0063] The device object of the present invention is composed of a system of suction dampers (1) consisting of cylinders (A, B, C) and designed to implement the reversibility of the operation between heating and cooling (2), a refrigerant circuit comprising: one cold exchanger (2) and a hot exchanger (3) located between the intake damper system (1) and the delivery damper system (4) consisting of cylinders (D, E, F) also designed to implement the reversibility of operation in a manner consistent with the suction damper system (1).

[0064] Advantageously, the reversible device (100) for the production of hot and cold air is designed to use a refrigerant fluid inside a refrigerant circuit consisting of a cold exchanger (2) and a hot exchanger (3) a natural refrigerant gas R744, carbon dioxide CO2, non-toxic and non-flammable.

[0065] The aforementioned R744 refrigerant gas represents an ecological and efficient alternative to fluorinated refrigerants since it does not contribute to the reduction of the ozone layer, has a lower impact than other refrigerants on the greenhouse effect and also has a high cooling power; in particular, the F-Gas Regulation of 2014 requires the phase out of refrigerants with a high GWP coefficient which indicates to what extent a gas is able to heat the atmosphere; this parameter for CO2 is equal to 1.

[0066] The cylinders (A, B, C, D, E, F) of the intake (1) and delivery (4) dampers are suitably provided with openings in the shell through which it is possible to manage the circulation of the air flow; in addition, the cylinders (B, E) are equipped with keyed baffles (B, E) to divert the air flow; in particular the cylinders (A, B, C) and the keyed septum (B) and the cylinders (D, E, F) and the keyed septum (E) are connected respectively to the shafts (L) and (R) equipped with ends of means for reducing friction (M) and (V) such as for example ball and/or roller and/or magnetic bearings and for allowing their rotation (N) and (Z).

[0067] Further, the cylinders (A, B, C) and the keyed septum (B) and the cylinders (D, E, F) and the keyed septum (E), the shafts (L) and (R) and the means for friction reduction (M, V, N, Z) to allow their rotation are connected respectively to the plenum (O) and to the plenum (T) which are advantageously provided with openings both on the sides (P) and (S) in correspondence of the external air and internal air channels, which from the sides (Q) and (U) correspond to the cold (2) and hot (3) exchanger; in particular the plenums (0, T) are equipped with air sealing systems (10) and (14) such as: gaskets in different materials, for example plastic and/or metal and/or elastic, between the cylinder and the air passage opening (11,15) in correspondence of the openings (P, Q) and (S, U), and between the internal cylinders and the intermediate cylinders (12, 16) and between the intermediate and external cylinders (13, 17).

[0068] The reversible device (100) according to the present invention is provided with a refrigeration circuit comprising a cold exchanger (2) crossed by the air flow moved by a fan (18) dedicated to this exchanger, and a hot exchanger (3) crossed by the air flow moved by a fan (19) dedicated to this hot exchanger (3), said cold (2) and hot (3) exchangers are connected to the compressor (20) by means of refrigerant pipes and said suction dampers (1) and (4) are motorized by means of one or more actuators (38).

[0069] When the device operates in heating mode, ice may form on the finned surfaces of the cold exchanger (2), especially in certain conditions of temperature and relative humidity of the outside air.

[0070] The formation of ice leads to a decline in the thermal exchange performance of the cold exchanger (2), with consequent lowering of the refrigerant pressure in the suction branch of the compressor, causing the progressive decrease of the COP and the shutdown of the unit due to the intervention of the protections low pressure installed in the refrigerant circuit.

[0071] In traditional heat pumps, in order to eliminate the ice formed, the refrigeration cycle is reversed so that the exchanger in contact with the outside air is crossed by a flow of high-temperature refrigerant that produces defrosting; however, this technique presents problems if applied to refrigeration circuits that use CO2 refrigerant in the transcritical cycle.

[0072] For this reason, the reversible device (100) object of the present invention provides for the defrosting phase to be carried out by means of an advantageous direction of the flows, using the hot air generated through the hot exchanger (3).

[0073] In particular, the refrigeration circuit generates a heating (21-23) or cooling (22-24) air flow based on the position of the cylinders (A, B, C, D, E, F) and this makes it possible four distinct modes of operation based on the configurations of the air flows, i.e. based on the combinations of the positions of the ports of the cylinders of the intake (1) and delivery (4) dampers, including: [0074] Cooling: in this mode the air flow directed to the user is diverted inside the cold exchanger (2) by opening the ports (29, 30, 31, 32) of the cylinders of the intake dampers (1) and (4), while the air flow coming from the outside is diverted inside the hot exchanger (3) by opening the ports (25, 26, 27, 28) of the cylinders of the intake dampers (1) and delivery (4), and therefore towards the outside; in particular, the keyed septum (B) of the intake damper cylinders deflects the air in a certain direction with respect to the flow (for example: to the right or to the left). [0075] Heating: in this configuration the cylinders (A) and (D) rotate (for example at 90? counterclockwise) with respect to the position of the cooling mode, the cylinders (B, E) rotate (for example at 180? in the counterclockwise) with respect to the position to the position of the cooling mode, the cylinders (C, F) do not rotate with respect to the position of the cooling mode and the air flow from the conditioned environment is diverted towards the hot exchanger (3) by opening of the ports (29, 26, 27, 32) of the cylinders of the suction (1) and delivery (4) dampers, while the air flow coming from the outside is diverted towards the cold exchanger (2) by opening the ports (33, 30, 31, 34) of the cylinders of the suction (1) and delivery (4) dampers. [0076] First variant defrost: in this mode the air is taken from the external environment, the cylinders (A), (B) and (C) rotate (for example at 180? counterclockwise) with respect to the cooling position, the cylinders (D) and (E) remain stationary, the cylinder (F) rotates (for example at 270? counterclockwise) with respect to the cooling position, and the air flow from the outside is diverted towards the hot exchanger (3) and then towards the cold exchanger (2) by opening the ports (25, 26, 27) and (35, 36, 37) of the suction (1) and delivery (4) damper cylinders. [0077] Second variant defrost: in this mode the air is not taken from the external environment, the cylinders (A, B, D, E) are in the cooling mode position, the cylinders (C) and (F) rotate (e.g. example of 270? counterclockwise) with respect to the cooling position, and the air flow is diverted towards the hot exchanger (3) and then towards the cold exchanger (2) by opening the ports (26, 27) and (35, 36) of the cylinders of the intake (1) and delivery (4) dampers.

[0078] In particular, in the first and second defrosting variants, the fan (18) of the cold exchanger (2) is off, and the cold air is not sent into the delivery duct to avoid discomfort for the residents.

[0079] The reversible device (100) according to the present invention can be replicated at an industrial level in different types of air/air heat pumps, intended for various application areas, among which the following can be identified: [0080] stand alone monobloc heat pumps typical of railway air conditioning; [0081] stand alone monobloc heat pumps of the roof top type typical of air conditioning for industrial and commercial environments; [0082] ductable monobloc heat pumps used in the air conditioning of small rooms or in naval applications; [0083] split heat pumps, typically used in the air conditioning of small rooms, hotel air conditioning, bus air conditioning; [0084] split heat pumps typical of the air conditioning of small rooms, hotel air conditioning and naval applications.

[0085] The present invention provides for a further construction variant that finds application where the spaces available for installation are particularly limited (example of a railway vehicle).

[0086] This variant provides for the installation of an external unit on which the compressor of the refrigeration circuit is housed and an air handling unit which includes the heat exchangers and the system of deviating dampers suitable for reversing the operation between heating and cooling.

[0087] FIG. 21 shows the cooling configuration: the flow of air (47) coming from the air-conditioned environment is diverted by means of the damper (44) towards the cold exchanger (45), sucked in by the fan unit and diverted by the damper (42) in the delivery duct (40) to the air-conditioned environment. The flow of air (39) coming from the outside is diverted by means of the damper (44) towards the hot exchanger (46) and subsequently expelled (41) into the external environment by means of the damper (43).

[0088] FIG. 22 shows the configuration in heating mode: the air flow (47) coming from the conditioned environment is diverted by means of the damper (44) towards the hot exchanger (46), sucked in by the fan unit and diverted by the damper (43) in the delivery duct (41) to the air-conditioned environment. The flow of air (39) coming from the outside is diverted by means of the damper (44) towards the cold exchanger (45) and subsequently expelled (40) into the external environment by means of the damper (42).