Outdoor unit for heat pump and heat pump

Abstract

The invention relates to an outdoor unit for a heat pump and the heat pump. An outdoor unit (1) for a heat pump (78) comprises: a housing (2); at least a portion of the refrigerant fluid circuit (3) having at least a first heat exchanger (4) housed in the housing (2); a fan (8) housed in the housing (2) and operable to convey an air flow through the housing (2) and through the first heat exchanger (4) for heat exchange between the air flow and the refrigerant fluid; a fan carrier drawer (10) having a fan seat (11) for removably housing a fan (8), and one or more translating members (13) that interact with corresponding translating guides (14) of a fixed support structure (15) of a housing (2) to allow for guiding the fan carrier drawer (10) into and out of the housing (2).

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the priority of Italian patent application No. 102023000019899 filed on September 27, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The invention relates to an outdoor unit of a heat pump and to a heat pump, for example for heating and / or cooling air and / or water, for example in a system for heating and / or cooling rooms and / or water. Background Art

[0004] The heat pump includes a circulation loop of a refrigerant fluid, a first heat exchanger disposed in the loop (e.g., acting as a refrigerant fluid evaporator), a compressor disposed in the loop and downstream of the first heat exchanger (e.g., acting as a refrigerant fluid condenser), an expansion valve disposed in the loop and downstream of the compressor, and disposed in the loop and downstream of the condenser and upstream of the evaporator. The expressions "downstream" and "upstream" refer to the first circulation direction of the refrigerant fluid in at least the first operating mode. The compressor can operate to extract a refrigerant fluid in a gas phase and at a low pressure from the first heat exchanger (evaporator), compress the refrigerant fluid, and push it into a second heat exchanger (condenser). Inside the second heat exchanger (condenser), the compressed refrigerant fluid releases heat and condenses at a high pressure. After leaving the second heat exchanger (condenser), the refrigerant fluid passes through an expansion valve, which decompresses the refrigerant fluid, turning the refrigerant fluid into a decompressed liquid phase with a possibly less gas phase content. The decompressed liquid refrigerant fluid is delivered, again due to the suction effect of the compressor, to a first heat exchanger (evaporator) where it absorbs heat and evaporates at a low pressure before being drawn and compressed again by the compressor.

[0005] The refrigerant fluid changes state in the first heat exchanger (evaporator), from liquid to gas by absorbing heat, and in the second heat exchanger (condenser), from gas to liquid by releasing heat. Then, the environment provided with the heat exchanger used as the evaporator is cooled, while the environment provided with the heat exchanger used as the condenser is heated.

[0006] It is also known to connect the compressor in the circuit by inserting a (four-way) switching valve which allows reversing the compression direction and reversing the circulation direction of the refrigerant fluid (from a first direction to a second direction) and switching the function of the first heat exchanger from evaporator to condenser and of the second heat exchanger from condenser to evaporator, thereby allowing cooling and heating of the space in which the first heat exchanger and the second heat exchanger are arranged.

[0007] A known heat pump as described above may be used in a heating mode (eg, during the winter months), extracting heat from the outside air and introducing the heat into the building.

[0008] In this case, the refrigerant fluid passes through the expansion valve, becomes a liquid-vapor mixture at low pressure, and then enters the first heat exchanger (which acts as an evaporator) provided outside, where the liquid-vapor mixture absorbs heat until it becomes vapor at a low temperature, and then the vapor is extracted and compressed by the compressor, causing the temperature to rise, and the hot and compressed vapor is pushed from the compressor outlet into the second heat exchanger (which acts as a condenser), where the vapor releases heat (for example, to a water circuit for heating the indoor environment), and changes from a gas phase to a liquid phase again, thereby releasing the heat of liquefaction. The liquid refrigerant fluid returns to the expansion valve, and the cycle repeats.

[0009] By reversing the cooling cycle (e.g. via a (four-way) switching valve), the same heat pump can be used in cooling mode (e.g. in the summer months), where the refrigerant fluid evaporates in the second heat exchanger (indoor environment) and condenses in the first heat exchanger (outdoor environment).

[0010] It is known to provide an outdoor unit of a heat pump, which is intended to be arranged outside an environment intended to be heated and / or cooled (e.g. outside a building), wherein the outdoor unit comprises:

[0011] case;

[0012] at least a portion of a refrigerant fluid circuit having at least a first heat exchanger and optionally a compressor, an expansion valve, and in some cases also a second heat exchanger, all of which are housed in a housing,

[0013] A fan (eg, an axial flow fan) is housed in the housing and is operable to convey an airflow through the housing and through the first heat exchanger to exchange heat between the airflow and the refrigerant fluid.

[0014] For reasons of space and aesthetics, the components of the outdoor unit need to be arranged in a compact and integrated manner within the housing. On the other hand, for reasons of performance and heat exchange efficiency, the first heat exchanger and the fan extend over a very large area of ​​the outdoor unit and interact closely with the housing and other components of the outdoor unit.

[0015] The fan itself is the most stressed component in the outdoor unit mechanically (impeller, vibration, friction, icing), thermally (temperature changes between summer and winter), chemically (humidity, condensation, atmospheric pollutants), and electrically (fan motor), and therefore requires maintenance, repair, and replacement.

[0016] In the prior art, intervention on the fan requires a complete and very demanding (time, cost, space) disassembly of the entire outdoor unit, which is difficult to carry out in the installation environment, or requires the entire outdoor unit to be removed from the heating / cooling system (in the case of intervention on the refrigerant circuit conductors or on the water pipes of the heating water circuit) and transported to a service center for maintenance intervention on the fan, especially if there are no spare parts for the fan. Both intervention modes are unsatisfactory, slow and costly. Summary of the invention

[0017] The object of the invention is to provide an outdoor unit for a heat pump of the type described in the introduction, which has features such as facilitating maintenance / replacement / repair interventions for the fan.

[0018] This object and other objects are achieved by an outdoor unit for a heat pump according to the invention.The invention also provides advantageous and preferred embodiments.

[0019] According to one aspect of the present invention, an outdoor unit for a heat pump comprises:

[0020] case;

[0021] at least a portion of a refrigerant fluid circuit having at least a first heat exchanger housed in the housing and optionally a compressor and / or an expansion valve and / or a second heat exchanger housed in the housing,

[0022] a fan contained in the housing and operable to convey an airflow through the housing and through the first heat exchanger to exchange heat between the airflow and the refrigerant fluid,

[0023] an optional electrical control system housed in the housing to power and control the compressor and fan,

[0024] A fan-holder drawer is received in the housing and has:

[0025] a fan seat, the fan seat being used to detachably accommodate the fan, and

[0026] One or more translation members interact with corresponding translation guides of the fixed support structure of the housing to allow the fan bracket drawer to be inserted into and removed from the housing along an insertion direction at an access side of the outdoor unit.

[0027] This allows easier and faster removal and insertion of the fan than in the prior art, and facilitates fan maintenance / repair / replacement interventions.

[0028] According to one aspect of the present invention, the shell can be opened on the approach side by manipulating the outer wall part (the manipulation is different from the removal and insertion movement of the fan bracket drawer) to separate the outer wall part from the fixed support structure, and the fan bracket drawer can only be inserted and removed relative to the shell when the outer wall part is separated from the fixed support structure.

[0029] This avoids the risk of accidental access to internal components of the outdoor unit, as well as the risk of accidental and undesired opening of the outdoor unit due to the insertion and extraction mechanism of the fan holder drawer. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to better understand the present invention and appreciate its advantages, some non-limiting embodiments will be described below with reference to the accompanying drawings, in which:

[0031] Figure 1 is a perspective view of an outdoor unit of a heat pump according to an embodiment, Figure 1.1 Shows Figure 1 Detail of the outdoor unit in which the outer wall section is screwed to the fixed support structure, Figure 1.2 and Figure 1.3 Shown is the removal of the outer wall portion Figure 1 The outdoor unit in

[0032] Figure 2 , Figure 2.1 , Figure 2.2 , Figure 2.3 shows the path of the power supply cable and / or signal cable of the outdoor unit according to the embodiment,

[0033] Figure 3.1 , Figure 3.2 , Figure 3.3 is a perspective view of a sequence of taking out a fan from a housing of an outdoor unit using a fan holder drawer according to an embodiment,

[0034] Figure 4.1 and Figure 4.2 is a perspective view of a slide guide of an outdoor unit housing according to an embodiment, and Figure 4.3 The corresponding sliding pads of the fan bracket drawer are shown,

[0035] Figure 5 is a front view of an assembly of a fan and a fan bracket drawer of an outdoor unit according to an embodiment, Figure 5.1 Shows Figure 5 Details of the components in Figure 5.2 and Figure 5.3 yes Figure 5 Cross-sectional views of two different vertical sections of the component,

[0036] Figure 6 is a top view of the fan bracket drawer inserted into the outdoor unit housing, Figure 6.1 yes Figure 6 A magnified view of the middle seal area. Figure 6.2 , Figure 6.3 , Figure 6.4 is a perspective view of an upper portion of a fan bracket drawer forming a ventilation channel for electrical components, and Figure 6.5 is a vertical cross-sectional view of a ventilation channel for electrical components,

[0037] Figure 7.1 and Figure 7.2 is a rear perspective view of a first access cover of the ventilation channel,

[0038] Figure 8.1 and Figure 8.2 is a rear perspective view of a second access cover of the ventilation channel,

[0039] Figure 9.1 , Figure 9.2 , Figure 9.3 This is a three-dimensional diagram of the internal support frame of the outdoor unit.

[0040] Fig.10 is a schematic diagram of a heat pump according to an embodiment. DETAILED DESCRIPTION

[0041] Referring to the drawings, the outdoor unit 1 for the heat pump 78 and / or the outdoor unit 1 of the heat pump 78 includes:

[0042] Shell 2,

[0043] at least a portion of a refrigerant fluid circuit 3 having at least a first heat exchanger 4, an optional compressor 5 and / or an expansion valve 6, and an optional second heat exchanger 7 accommodated in the housing 2,

[0044] a fan 8 housed in the housing 2 and operable to convey an airflow through the housing 2 and through the first heat exchanger 4 to exchange heat between the airflow and the refrigerant fluid,

[0045] An optional electrical control system 9, which is housed in the housing 2, to supply power to and control the compressor 5 and the fan 8,

[0046] A fan bracket drawer 10 is accommodated in the housing and has:

[0047] a fan holder 11 for removably receiving the fan 8 to form an assembly or set 12 of the fan 8 and the fan holder drawer 10; and

[0048] - one or more translation members (advantageously, sliding pads 13, alternatively, translation gears or rolling translation members) which interact (in a sliding manner) with corresponding translation guides (advantageously, sliding guides 14, alternatively, translation reversal gears or rolling translation reversal members or rolling tracks) of the fixed support structure 15 of the housing 2 to guide the fan holder drawer 10 into and out of the housing 2 along the insertion direction 27 at the approach side 16 of the outdoor unit 1 ( Figure 3.2 , Figure 4.1 , Figure 4.3 ).

[0049] This allows easier and faster extraction and insertion of the fan 8 than in the prior art and facilitates maintenance / repair / replacement interventions of the fan 8 .

[0050] According to an embodiment, the housing 2 can be opened on the approach side 16 by manipulating the outer wall portion 17 (e.g., a wall having a protective grille) (the manipulation is different from the removal and insertion movement of the fan bracket drawer 10) to separate the outer wall portion 17 from the fixed support structure 15, and the fan bracket drawer 10 can only be inserted and removed relative to the housing 2 when the outer wall portion 17 is separated from the fixed support structure 15.

[0051] This avoids the risk of accidental access to internal components of the outdoor unit 1 , as well as the risk of accidental and undesired opening of the outdoor unit 1 due to the insertion and extraction mechanism of the fan bracket drawer 10 .

[0052] The outer wall portion 17 may be a front wall portion which also forms a protection and air passage grille ( Figure 1 , Figure 1.1 The disassembly operation may include, for example, unscrewing the fixing screws 18 and / or disassembling the insertion coupling of the outer wall part 17 from the fixing support structure 15 .

[0053] Description of Fan Stand Drawer 10

[0054] According to an embodiment, the fan support drawer 10 is made of a foamed synthetic material (e.g. expanded polypropylene) (except for the translation member). This provides a very light structure that is resistant to environmental influences (temperature, humidity), corrosion-resistant, and suitable for damping possible vibrations of the fan 8 better than metal materials or hard plastic materials.

[0055] According to an embodiment, the fan bracket drawer 10 includes two halves 19, 20, such as a lower half 19 and an upper half 20, which are in the form of a clamp and are configured as follows:

[0056] - can be moved towards each other into a closed position ( Figure 3.2 ), in which they surround the fan 8 in a form-fitting manner,

[0057] - can be moved away from each other or disassembled into an open position ( Figure 3.3 ), in which open position the fan 8 can be removed from (the fan seat 11 of) the fan bracket drawer 10.

[0058] The fan 8 is preferably an axial flow fan having an impeller 21, a motor 22 for rotating the impeller, and a drum 23, which supports the motor 22 and the impeller 21 and defines an air passage 24 of the fan 8. The drum 23 has a tubular portion 25 ( Figure 3.3 ).

[0059] The halves 19, 20 define in the closed position a tubular fan seat 11 coupled to the outer surface of the fan 8, in particular the drum 23, wherein:

[0060] - the flanges 26 of the drum 23 clamp between them the parts 11 ′ of the fan base 11 belonging to the two half-bodies 19 , 20 , these parts 11 ′ having a slightly excessive axial thickness 28 relative to the axial distance 29 between the flanges 26 , so as to obtain an interference coupling between the fan and the half-bodies 19 , 20 , and / or

[0061] - the drum 23 (e.g. at least one of the flanges 26) forms at least one pair of first opposing straight edges 30, and the fan base 11 forms at least one pair of second opposing straight edges 31, which, in the correct angular position of the fan 8 relative to the fan support drawer 10, face and abut the first opposing straight edges 30 ( Figure 3.3 , Figure 5.1 ), thereby forming a geometric position reference, and / or

[0062] - the fan holder 11 forms a plurality of cavities 32 (eg distributed at a constant pitch in the circumferential direction) which accommodate the reinforcing ribs 33 of the drum 23 of the fan 8, thereby avoiding encroachment on the space between the reinforcing ribs 33 and the fan bracket drawer 10 ( Figure 3.3 , Figure 5.3), and / or - the halves 19, 20 each form one half (upper and lower) of the fan holder 11, and define a horizontal joint interface 34 at approximately half the height of the fan holder 11, which facilitates the manufacture of the halves 19, 20 by molding / expanding the synthetic material, and also facilitates the opening and closing of the fan holder 11 and the insertion and removal of the fan 8 into and from the fan holder drawer 10 ( Figure 3.3 ), and / or

[0063] - At the joint interface 34, the halves 19, 20 form a protrusion 35 and a corresponding recess 36 ( Figure 3.3 , Figure 5.2 ), the protrusion and the corresponding recess can be inserted into each other in the closed position to form a temporary coupling of the half bodies 19, 20 during the steps of inserting and removing the fan bracket drawer 10 into the housing 2 and from the housing.

[0064] According to the embodiment ( Figure 5.2 ), the fan support drawer 10 (preferably the lower half 19) forms at least one fan wiring channel 37, which extends in the foamed synthetic material from an inlet opening 37' on the lower side of the fan support drawer 10 to an outlet opening 37" on the lower side of the fan seat 11. This facilitates the electrical wiring of the fan 8 and avoids uncontrolled passage of electrical cables in the moving area of ​​the fan support drawer 10 and the fan 8 itself.

[0065] According to the embodiment ( Figure 1.2 , Figure 2 , Figure 2.3 , Figure 5 , Figure 5.1 , Figure 5.3 ), the fan bracket drawer 10 forms a first coupling portion 38 on two opposite lateral sides, which is aligned with a second coupling portion 39 of the fixed support structure 15 (for example, formed in two opposite vertical walls 40 of the fixed support structure 15) in the insertion direction 27, so that when the fan bracket drawer 10 is inserted into the housing 2 and reaches the insertion position relative to the fixed support structure 15, the first coupling portion 38 engages with the second coupling portion 39, thereby, in addition to the contact / support between the translation member (sliding pad 13) and the translation guide (sliding guide 14), a shape coupling (preferably a dovetail coupling) is formed between the fan bracket drawer 10 and the fixed support structure 15 in the insertion position of the fan bracket drawer 10. As a result, the fan bracket drawer 10 stiffens and stabilizes the fixed support structure 15, and vice versa, in particular in a direction transverse to the insertion direction 27.

[0066] According to an embodiment, the translation member (sliding pad 13) and the translation guide (sliding guide 14) are located on the lower side of the fan bracket drawer 10, and the first coupling portion 38 and the second coupling portion 39 are basically located at half the height (±15%) of the fan bracket drawer 10, thereby avoiding the undesirable collapse of the fixed support structure 15 toward the outside at the space occupied by the fan bracket drawer 10.

[0067] A further advantage is that each of the first coupling parts 38 is a dovetail-shaped protrusion formed by two half bodies 19, 20, so that in the inserted position of the fan bracket drawer 10, the half bodies 19, 20 are clamped together in a closed position by coupling the first coupling part 38 with the second coupling part 39.

[0068] According to an embodiment, in the inserted position, the fan holder drawer 10 is inserted into the fixed support structure 15 like a plug and forms outer peripheral surfaces 42, 44 which (sealingly) engage corresponding inner peripheral surfaces 43, 45 of the fixed support structure 15 to prevent the escape of an air flow parallel to the main air flow generated by the fan 8 through the air channel 24. In this case, the feature "sealingly" does not mean watertight, but rather adherent, e.g. without creating any significant additional flow channel.

[0069] A particular advantage is that the drum 23 of the fan 8 prevents the outer peripheral surfaces 42, 44 of the fan support drawer 10 from collapsing inwardly, and the engagement between the first (dovetail) coupling portion 38 and the second (dovetail) coupling portion 39 prevents unwanted collapse of the outer peripheral surfaces 43, 45 of the fixed support structure 15 toward the outside.

[0070] The fan bracket drawer 10 forms two first opposite vertical side walls 41, which (in the inserted position) face the corresponding second opposite vertical wall 40 of the fixed support structure 15, wherein the first opposite vertical side walls 41 form a first sealing surface 42 (of the outer peripheral surface) that is wedge-shaped and inclined in the insertion direction 27, and the second opposite vertical wall 40 forms a vertical sealing rib 43 (of the inner sealing surface) that is sealingly engaged with the first sealing surface 42 in the inserted position ( Figure 6.1 ).

[0071] This bilateral sealing engagement between the fan bracket drawer 10 and the fixed support structure 15 avoids the occurrence of undesired escaping air flows and compensates for dimensional manufacturing tolerances of the portion of the fixed support structure 15 formed by molding the foamed synthetic material and of the fan bracket drawer 10 .

[0072] The first opposite vertical side wall 41 and the second opposite vertical wall 40 are made of a foamed synthetic material or expanded polypropylene taking advantage of its reduced density, its corrosion resistance, its rigidity and its ability to dampen vibrations.

[0073] According to another embodiment ( Figure 6.2 ), the fan bracket drawer 10 forms a second upper sealing surface 44 (of the outer sealing surface) that is wedge-shaped and inclined along the insertion direction 27, and the second upper sealing surface is used to sealingly engage the corresponding third upper sealing surface 45 (of the inner sealing surface) of the fixed support structure 15 in the insertion position and compensate for the dimensional tolerance of the fan bracket drawer 10 and the fixed support structure 15.

[0074] In order to accommodate an auxiliary seal or auxiliary spacer for roughly compensating the dimensional tolerance of the fan bracket drawer 10 and / or the fixed support structure 15, a groove 45 is also formed near the second upper sealing surface 44 on the side facing the approach side 16 ( Figure 6.5 ).

[0075] According to the embodiment ( Figure 6.2 , Figure 6.4 , Figure 6.5 ), the fan bracket drawer 10 forms a cooling channel 46, which enables airflow communication between one or more auxiliary electric fans 47 and the power supply components of the compressor 5 (especially the inverter 48 and the inductor 49 (i.e., the inductance / reactance used to stabilize the current entering the inverter 48)), wherein the cooling channel 46 is separated from the air channel 24 of the fan 8.

[0076] Advantageously, the cooling channel 46 extends at least partially around the fan socket 11 on the outside.

[0077] Advantageously, the cooling channel 46 is delimited by a first channel surface 50 formed by the fan bracket drawer 10 and a second channel surface 51 formed by the fixed support structure 15, and the cooling channel 46 adopts its (closed) operating configuration only when the fan bracket drawer 10 is in the inserted position.

[0078] One or more auxiliary fans 47 are accommodated in corresponding auxiliary seats 52 formed in the cooling channel 46 (e.g., in the first channel surface 50) and are accessible from the outside of the cooling channel 46 through a first access opening 53 formed between the fan bracket drawer 10 and the fixed support structure 15 to manually position the one or more auxiliary fans 47 in an operating position (which will not allow the fan bracket drawer 10 to be removed) and in a flip position (which allows the fan bracket drawer 10 to be removed from the fixed support structure 15).

[0079] The first access opening 53 is provided with at least one first access cover 54 ( Figure 3.1) is closable and openable, preferably the first access cover is made of a foamed synthetic material (e.g. expanded polypropylene). Advantageously, the first access cover 54 delimits at the front (at the access side 16) an upper section ( Figure 1.2 , Figure 3.1 , Figure 6.4 , Figure 6.5 , Figure 7.1 , Figure 7.2 ).

[0080] The inverter 48 is accommodated in a corresponding inverter seat 55 and protrudes into the cooling channel 46 (in an installation position that does not allow the fan bracket drawer 10 to be removed), and can be removed from the cooling channel 46 through a second access opening 53' formed between the fan bracket drawer 10 and the fixed support structure 15 ( Figure 1.2 , Figure 3.1 ).

[0081] The second access opening 53' can be opened by a second access cover 54' ( Figure 3.1 ) is closed and opened, and the second access cover is preferably made of a foamed synthetic material (e.g., expanded polypropylene). By engaging the first protrusion 56 of the second access cover 54' in the first groove 57 of the fan bracket drawer 10, and by engaging the second protrusion 56' of the second access cover 54' in the second groove 57' of the fixed support structure 15, the second access cover 54' can be coupled to the fan bracket drawer 10 and coupled to the fixed support structure 15 in a guided manner ( Figure 3.2 , Figure 6.3 , Figure 8.1 ).

[0082] The removal and insertion direction of the second access cover 54 ′ is transverse to the removal and insertion direction of the inverter 48 so as to lock the inverter 48 in the installation position.

[0083] The first channel surface 50 forms a cable groove 58 in which a power supply cable (eg for the reactor 49 ) extends.

[0084] Description of the fixed support structure 15

[0085] According to an embodiment, the fixed support structure 15 comprises: a lower base wall 59, two opposite side walls 40 and an upper wall 60, all of which are made of a foamed synthetic material (preferably expanded polypropylene); and a metal support frame 61 (for example, made of aluminum), which forms two lateral columns 62 and a crossbar 63, which are open in a C shape toward the access side 16, and when the fan bracket drawer 10 is removed from the housing 2, the metal support frame supports the upper wall 60 ( Figure 9.1 , Figure 9.2 , Figure 9.3 ).

[0086] The upper wall 60 made of foamed synthetic material forms a seat for accommodating and / or supporting the electrical components of the compressor 5 (inverter 48, inductor 49, TDM digital multiplexing electronic board 80), and possibly also forming the energy management electronic board 81 of the electrical control system 9, and possibly the filter board 76.

[0087] According to the embodiment ( Figure 4.1 ), the outdoor unit 1 forms a condensate discharge channel 68 in the (trapezoidal) gap between the base wall 59 of the fixed support structure 15 and the fan bracket drawer 10 to discharge condensate from the fan 8 toward the bottom of the outdoor unit 1.

[0088] Description of the translation mechanism of the fan support drawer 10

[0089] According to an embodiment, the sliding pad 13 is positioned on the lower side (of the lower half 19) of the fan bracket drawer 10 and comprises two sheet metal profiles (e.g. made of stainless steel) extending in the insertion direction 27 and having an angular cross-sectional shape to mate with the translation guide 14 ( Figure 4.3 ) creates vertical and horizontal support constraints transverse to the insertion direction 27.

[0090] The sliding pads 13 are fixed to the fan bracket drawer 10 by screws screwed into a hard plastic insert embedded in the foamed synthetic material of the fan bracket drawer 10 .

[0091] Similarly, the sliding guide 14 is positioned in the base wall 59 of the fixed support structure 15 and comprises two sheet metal profiles (for example made of stainless steel) extending in the insertion direction 27 and having an angular cross-sectional shape to generate vertical and horizontal support constraints transverse to the insertion direction 27 relative to the sliding pad 13 ( Figure 4.1 ).

[0092] The sliding guide 14 is fixed to the base wall 59 by means of screws screwed into a hard plastic insert embedded in the foamed synthetic material of the base wall 59 .

[0093] Each sliding guide 14 forms, at the screw of the corresponding sliding pad 13 , a throat 64 extending in the insertion direction 27 .

[0094] Similarly, each sliding pad 13 forms a throat 64 extending in the insertion direction 27 at the screw of the corresponding sliding guide 14. This avoids encroaching on the space between the head of the screw and the metal profile of the sliding guide 14 and the sliding pad 13.

[0095] The sliding guide 14 (on the approach side 16) forms a first fixing projection 65 with a threaded hole 66 (eg, a nut), while the corresponding sliding pad 13 (also on the approach side 16) forms a second fixing projection 67 with a hole ( Figure 4.1 , Figure 4.3 ), the hole of the second fixing protrusion is used to receive a fixing screw that can be screwed into the threaded hole 66 of the first fixing protrusion 65, thereby locking the fan bracket drawer 10 in the inserted position.

[0096] According to alternative embodiments, the translation member and corresponding translation guide may include one or more of the following:

[0097] - translation gear,

[0098] - rolling mechanism,

[0099] - telescopic mechanism,

[0100] - Articulated quadrilateral.

[0101] According to an embodiment, the outdoor unit 1 comprises a wiring path system 69 for power supply cables and signal cables, the wiring path system comprising at least one front wiring segment 70, the at least one front wiring segment being constrained to (the base wall 59 of) the fixed support structure 15 and extending on the approach side 16 relative to the fan bracket drawer 10 in the inserted position and on both lateral sides ( Figure 2 , Figure 2.1 , Figure 2.2 ) so that when the fan bracket drawer 10 is in the insertion position, the front wiring section 70 can be freely approached from the approach side 16, and when the fan bracket drawer 10 is removed from the housing 2 and inserted into the housing, the front wiring section does not infringe on the space of the fan bracket drawer 10.

[0102] At the front wiring section 70 (preferably, at a low lateral angle of the fan bracket drawer 10), one or more quick electrical plug-socket connectors 71 are provided to quickly electrically and / or signal connect the cables of the front wiring path 70 with the cables of the internal wiring path 72 extending into the fan wiring channel 37 of the fan bracket drawer 10. At the quick electrical connector 71, the fan bracket drawer 10 includes an access cavity 73 to increase the access space for connecting and disconnecting the quick electrical connector 71 before removing the fan bracket drawer 10 and after inserting the fan bracket drawer, respectively.

[0103] Additionally or alternatively, the wiring path system 69 comprises at least a first rear wiring segment 74 and a second rear wiring segment 75, both of which are constrained to the fixed support structure 15 (constrained to the corresponding vertical wall 40 and possibly to the upper wall 60, for example, to the lateral uprights 62 and crossbars 63 of the metal support frame 61) and extend on the side of the (inserted) fan bracket drawer 10 opposite to the approach side 16 ( Figure 2.3 ), and extend spaced apart from each other on two opposite lateral sides of the fan bracket drawer 10. This allows reducing electromagnetic influence between the cables (e.g., signal cables) of the first rear wiring path 74 and the cables (e.g., power cables) of the second rear wiring path 75.

[0104] The constraining of the wiring paths to the fixed support structure 15 is performed by a plurality of clips and / or clamps.

[0105] The invention allows an ergonomic and compact arrangement of the components of the outdoor unit 1 , as well as quick and easy access to the fan 8 for maintenance and replacement purposes.

[0106] The fan 8 is advantageously removed from the housing 2 by the following steps.

[0107] - Remove the outer wall part 17 ( Figure 1.1 , Figure 1.2 ),

[0108] - Remove the first access cover 54 in the removal direction along the insertion direction 27 ( Figure 3.1 ),

[0109] - transversely to the insertion direction 27 ( Figure 3.1 Remove the second access cover 54' in the direction of the right side of the

[0110] - Remove the inverter 48 from the inverter seat of the fixed support structure 15 and support the inverter 48 on, for example, the heat pump group box 77 accommodating the compressor 5 and the expansion valve 6, without disconnecting the sufficiently long cables of the inverter 48 ( Figure 3.1 ),

[0111] - Disconnect the quick electrical connector 71,

[0112] - unscrew the locking screws from the fixing projections 65, 67,

[0113] - The fan holder drawer 10 is removed in a guided manner along the insertion direction 27 towards the access side 16 by sliding the sliding pad 13 on the sliding guide 14 ( Figure 3.2 ),

[0114] - Open the fan seat 11 by removing the upper half 20 from the lower half 19 and remove the fan 8 from the fan seat 11 ( Figure 3.3 ).

[0115] The fan 8 is advantageously inserted into the housing 2 by the following steps:

[0116] - inserting the fan 8 into the fan holder 11 and closing the fan holder 11 by bringing the upper part 20 closer to the lower part 19,

[0117] - guided insertion into the fan holder drawer 10 along the insertion direction 27 by sliding the sliding pad 13 onto the sliding guide 14,

[0118] - screw the locking screw into the fixing projections 65, 67,

[0119] - inserting the inverter 48 into the inverter seat of the fixed support structure 15,

[0120] - Connect the quick electrical connector 71,

[0121] - transversely to the insertion direction 27 ( Figure 3.1 Insert the second access cover 54' in the direction of the left side of

[0122] - inserting the first access cover 54 in the insertion direction 27,

[0123] - Reassemble the outer wall section 17.

[0124] Description of an embodiment of the heat pump 1

[0125] According to the embodiment ( Fig.10 ), the heat pump 78 includes a refrigerant fluid circuit 3, a first heat exchanger 4 (e.g., acting as a refrigerant fluid evaporator) disposed in the circuit 3, a compressor 5 disposed in the circuit 3 and downstream of the first heat exchanger 4, a second heat exchanger 7 (e.g., acting as a refrigerant fluid condenser) disposed in the circuit 3 and downstream of the compressor 5, and an expansion valve 6 disposed in the circuit 3 and between the second heat exchanger 7 and the first heat exchanger 4. The terms "downstream" and "upstream" refer to a first circulation direction of the refrigerant fluid in at least the first operating mode.

[0126] The compressor 5 is operable to extract a refrigerant fluid in a gas phase and at a low pressure from the first heat exchanger 4 (evaporator), compress the refrigerant fluid, and push it into the second heat exchanger 7 (condenser). Inside the second heat exchanger 7 (condenser), the compressed refrigerant fluid releases heat and condenses at a high pressure. After leaving the second heat exchanger 7 (condenser), the refrigerant fluid passes through the expansion valve 6, which decompresses the refrigerant fluid, turning the refrigerant fluid into a decompressed liquid phase with a possibly lower gas phase content. Again due to the suction effect of the compressor 5, the decompressed liquid refrigerant fluid is delivered to the first heat exchanger 4 (evaporator), where the refrigerant fluid absorbs heat and evaporates at a low pressure before being extracted and compressed by the compressor 5 again.

[0127] The refrigerant fluid changes state in the first heat exchanger 4 (evaporator), from liquid to gas by absorbing heat, and in the second heat exchanger 7 (condenser), from gas to liquid by releasing heat. The environment provided with the heat exchanger acting as an evaporator is then cooled, while the environment provided with the heat exchanger acting as a condenser is heated.

[0128] The compressor 5 is connected in the circuit 3 by inserting a (four-way) switching valve 79, which allows reversing the compression direction and reversing the circulation direction of the refrigerant fluid (from the first direction to the second direction), and switching the function of the first heat exchanger 4 from the evaporator to the condenser, and switching the function of the second heat exchanger 7 from the condenser to the evaporator, thereby allowing cooling and heating of the space in which the first heat exchanger 4 and the second heat exchanger 7 are arranged.

[0129] The heat pump 78 comprises an outdoor unit 1 described so far, intended to be positioned in an outdoor environment, and an indoor unit possibly intended to be positioned inside a building and connected to an application (eg a heating / cooling system with a main water circuit).

[0130] Alternatively, the outdoor unit 1 itself may include the first heat exchanger 4 and the second heat exchanger 7 , and thereby the entire refrigerant circuit 3 .

[0131] LIST OF REFERENCE NUMERALS IN THE DRAWINGS Outdoor unit 1

[0132] Shell 2

[0133] Refrigerant fluid circuit 3

[0134] The first heat exchanger 4

[0135] Compressor 5

[0136] Expansion valve 6

[0137] Second heat exchanger 7

[0138] Fan 8

[0139] Electronic control system 9

[0140] Fan bracket drawer 10

[0141] Fan seat 11

[0142] Fan seat part 11'

[0143] Set 12 of fan 8 and fan support drawer 10

[0144] Translation member, sliding pad 13

[0145] Translation guide, sliding guide 14

[0146] Fixed support structure 15

[0147] Approach side 16

[0148] Outer wall portion 17

[0149] Fixing screw 18

[0150] Lower body 19

[0151] Upper body 20

[0152] Impeller 21

[0153] Electric motor 22

[0154] Roller 23

[0155] Air channel 24

[0156] Tubular part 25

[0157] Flange 26

[0158] Insertion direction 27

[0159] Axial thickness 28

[0160] Axial distance 29

[0161] First relative straight edge 30 (fan)

[0162] Second opposite straight edge 31 (drawer)

[0163] Cavity 32

[0164] Reinforcement rib 33

[0165] Bonding interface 34

[0166] Protrusion 35

[0167] Recess 36

[0168] Fan wiring channel 37

[0169] Entrance opening 37'

[0170] Outlet opening 37”

[0171] First coupling portion 38

[0172] The second coupling portion 39

[0173] Vertical wall 40 of the fixed support structure

[0174] The opposite vertical side walls 41 of the drawer

[0175] First sealing surface 42

[0176] Sealing rib 43

[0177] The second upper sealing surface 44 of the drawer The third upper sealing surface 45 of the fixed support structure The cooling channel 46

[0178] Auxiliary fan 47

[0179] Inverter 48

[0180] Reactor 49

[0181] First channel surface 50

[0182] Second channel surface 51

[0183] Auxiliary seat 52

[0184] First access opening 53

[0185] First access cover 54

[0186] Second access opening 53'

[0187] Second access cover 54'

[0188] Inverter seat 55

[0189] First protrusion 56

[0190] First groove 57

[0191] Second protrusion 56'

[0192] Second groove 57'

[0193] Cable groove 58

[0194] Base wall 59

[0195] Upper wall 60 Metal support frame 61 Lateral columns 62 Crossbar 63

[0196] Throat 64

[0197] First fixing protrusion 65 threaded hole 66

[0198] Second fixing protrusion 67 Condensate drain passage 68 Wiring routing system 69 Front wiring segment 70 Quick electrical connector 71 Internal wiring routing 72 Access cavity 73

[0199] The first wiring segment 74

[0200] Second wiring segment 75 filter board 76 heat pump unit 77

[0201] Heat pump 78

[0202] Switching valve 79 TDM board 80 energy management board 81.

Claims

1. An outdoor unit (1) for a heat pump (78), the outdoor unit comprising: - a housing (2), - at least a portion of a refrigerant fluid circuit (3), said at least a portion of the refrigerant fluid circuit having at least a first heat exchanger (4) accommodated in said housing (2), a fan (8) housed in the housing (2) and operable to convey an air flow through the housing (2) and through the first heat exchanger (4) to effect a heat exchange between the air flow and a refrigerant fluid, - a fan bracket drawer (10), which is accommodated in the housing (2) and has: - a fan seat (11) for detachably accommodating the fan (8), and - one or more translation members (13) which interact with corresponding translation guides (14) of a fixed support structure (15) of the housing (2) to allow the fan bracket drawer (10) to be guided along an insertion direction (27) into and out of the housing (2) on the approach side (16) of the outdoor unit (1).

2. The outdoor unit (1) according to claim 1, comprising: - a compressor (5) and an expansion valve (6) of the refrigerant fluid circuit (3), the compressor and the expansion valve being accommodated in the housing (2), - An electrical control system (9) housed in the housing (2) for supplying power to and controlling the compressor (5) and the fan (8).

3. The outdoor unit (1) according to claim 1 or 2, wherein: The housing (2) can be opened at the approach side (16) by manipulating the outer wall portion (17) to separate the outer wall portion (17) from the fixed support structure (15), wherein the manipulation is different from the removal and insertion of the fan bracket drawer (10), and the fan bracket drawer (10) can only be inserted and removed when the outer wall portion (17) is separated from the fixed support structure (15).

4. The outdoor unit (1) according to claim 1 or 2, wherein: The fan bracket drawer (10) is made of foamed synthetic material or expanded polypropylene.

5. The outdoor unit (1) according to claim 1 or 2, wherein: The fan bracket drawer (10) comprises two halves (19, 20), or a lower half (19) and an upper half (20), wherein the lower half and the upper half are in the form of a clamp and are configured as follows: - can be moved towards each other into a closed position in which the lower half and the upper half surround the fan (8) in a form-fitting manner, - can be moved away from each other into an open position in which the fan (8) can be removed from the fan seat (11).

6. The outdoor unit (1) according to claim 1 or 2, wherein: The fan (8) is an axial flow fan having an impeller (21), a motor (22) and a drum (23), wherein the drum supports the motor (22) and the impeller (21). wherein the drum (23) has a tubular portion (25) and defines an air passage (24) for the fan (8), the tubular portion having two end flanges (26), wherein the two halves (19, 20) in the closed position define a tubular fan seat (11) coupled to the outer surface of the drum (23), in: - the flange (26) of the drum (23) clamps together the portion (11') of the fan seat (11) belonging to the two half-bodies (19, 20), and the portion of the fan seat has an excessive nominal axial thickness (28) relative to the axial distance (29) between the flanges (26) to achieve an interference coupling between the fan (8) and the two half-bodies (19, 20), and / or - the drum (23) forms at least one pair of first relative straight edges (30), and the fan holder (11) forms at least one pair of second relative straight edges (31), and in the correct angular position of the fan (8) relative to the fan holder drawer (10), the at least one pair of second relative straight edges face and abut the first relative straight edges (30) and form a geometric position reference, and / or - the fan seat (11) forms a plurality of cavities (32) which accommodate the reinforcing ribs (33) of the drum (23) of the fan (8), and / or - the two halves (19, 20) respectively form the upper and lower halves of the fan base (11) and define a horizontal joint interface (34) at half the height of the fan base (11), and / or The two halves (19, 20) form a protrusion (35) and a corresponding recess (36) which can be inserted into each other in the closed position to form a temporary coupling of the two halves (19, 20) during the insertion and removal of the fan bracket drawer (10) into the housing (2).

7. The outdoor unit (1) according to claim 1 or 2, wherein: The fan bracket drawer (10) forms at least one fan wiring channel (37) extending in the foamed synthetic material.

8. The outdoor unit (1) according to claim 1 or 2, wherein: The fan bracket drawer (10) forms a first coupling portion (38) on two opposite lateral sides, and the first coupling portion is aligned with the second coupling portion (39) of the fixed support structure (15) in the insertion direction (27), so that when the fan bracket drawer (10) is inserted into the housing (2) and reaches an insertion position relative to the fixed support structure (15), the first coupling portion (38) engages with the second coupling portion (39), thereby forming a shape coupling in the shape of a dovetail coupling between the fan bracket drawer (10) and the fixed support structure (15) at the insertion position.

9. The outdoor unit (1) according to claim 8, wherein: The translation member or sliding pad (13) and the translation guide or sliding guide (14) are located on the lower side of the fan bracket drawer (10), and the first coupling portion (38) and the second coupling portion (39) are located at half ±15% of the height of the fan bracket drawer (10).

10. The outdoor unit (1) according to claim 8, wherein: Each of the first coupling parts (38) is a dovetail-shaped protrusion formed by the two half bodies (19, 20), so that in the inserted position of the fan bracket drawer (10), the two half bodies (19, 20) are locked together in their closed position by coupling the first coupling part (38) with the second coupling part (39).

11. The outdoor unit (1) according to claim 1 or 2, wherein: In the inserted position, the fan bracket drawer (10) is inserted into the fixed support structure (15) like a plug and forms an outer peripheral surface (42, 44) that sealingly engages a corresponding inner peripheral surface (43, 45) of the fixed support structure (15) to prevent the escape of air flow parallel to the main air flow through the air channel (24) of the fan (8).

12. The outdoor unit (1) according to claim 1 or 2, wherein: The fan bracket drawer (10) forms two first opposite vertical side walls (41) facing the corresponding second opposite vertical wall (40) of the fixed support structure (15), wherein the first opposite vertical side wall (41) forms a first sealing surface (42) inclined in a wedge shape along the insertion direction (27), and the second opposite vertical wall (40) forms a vertical sealing rib (43) sealingly engaged with the first sealing surface (42) in the insertion position, Wherein, the first opposite vertical side wall (41) and the second opposite vertical wall (40) are made of foamed synthetic material or expanded polypropylene.

13. The outdoor unit (1) according to claim 8, wherein: The fan bracket drawer (10) forms a second upper sealing surface (44) which is wedge-shaped and inclined along the insertion direction (27), and the second upper sealing surface is used to sealingly engage a corresponding third upper sealing surface (45) of the fixed support structure (15) in the insertion position, wherein the second upper sealing surface (44) and the third upper sealing surface (45) are made of foamed synthetic material or expanded polypropylene.

14. The outdoor unit (1) according to claim 2, wherein: The fan bracket drawer (10) forms a cooling channel (46) that connects one or more auxiliary electric fans (47) and power supply components (48, 49) of the compressor (5) in airflow communication, wherein the cooling channel (46) is separated from the air channel (24) of the fan (8).

15. The outdoor unit (1) according to claim 12, wherein: The cooling channel (46) is bounded by a first channel surface (50) formed by the fan bracket drawer (10) and a second channel surface (51), the first channel surface being formed by the fan bracket drawer (10) and the second channel surface being formed by the fixed support structure (15), and the cooling channel adopts its operating configuration only when the fan bracket drawer (10) is in the inserted position.

16. The outdoor unit (1) according to claim 2, wherein: The fixed support structure (15) comprises: a lower base wall (59), two opposite side walls (40) and an upper wall (60), wherein the lower base wall, the two opposite side walls and the upper wall are all made of foamed synthetic material or expanded polypropylene; and a metal support frame (61), wherein the metal support frame is made of, for example, aluminum, and the metal support frame forms two lateral columns (62) and a crossbar (63), wherein the two lateral columns are opened in a C shape toward the approach side (16), and when the fan bracket drawer (10) is removed from the housing (2), the metal support frame supports the upper wall (60), Therein, the upper wall (60) forms a seat for accommodating and supporting control and power supply components (48, 49, 80, 81, 76) of the compressor (5).

17. An outdoor unit (1) according to claim 1 or 2, wherein the outdoor unit has a condensate discharge channel (68), which is formed in a trapezoidal or funnel-shaped gap between the base wall (59) of the fixed support structure (15) and the fan bracket drawer (10) to discharge condensate from the fan (8) toward the bottom of the outdoor unit (1).

18. The outdoor unit (1) according to claim 1 or 2, wherein: The translation member (13) comprises a sliding pad (13) positioned on the lower side of the fan bracket drawer (10) and formed by two sheet metal profiles extending in the insertion direction (27), the sliding pad having an angled cross-sectional shape to generate a vertical and horizontal support constraint with the translation guide (14) transverse to the insertion direction (27), The translation guide (14) comprises a sliding guide (14), which is positioned in a base wall (59) of the fixed support structure (15) and is formed by two sheet metal profiles extending in the insertion direction (27), and has an angled cross-sectional shape to produce vertical and horizontal support constraints with the sliding pad (13) transverse to the insertion direction (27).

19. The outdoor unit (1) according to claim 18, wherein: The sliding guide (14) forms a first fixing protrusion (65) having a hole (66) on the approach side (16), and the corresponding sliding pad (13) forms a second fixing protrusion (67) on the approach side (16), the second fixing protrusion having a hole for receiving a fixing screw that can be screwed into the hole (66) of the first fixing protrusion (65) to lock the fan bracket drawer (10) in the inserted position.

20. The outdoor unit (1) according to claim 1 or 2, wherein: The outdoor unit (1) comprises a wiring path system (69) for power supply cables and signal cables, the wiring path system comprising: - at least one front wiring section (70) which is constrained to the fixed support structure (15) and extends on the access side (16) relative to the fan bracket drawer (10) in the insertion position and on two lateral sides of the fan bracket drawer (10) at a lower height relative to the space occupied by the fan bracket drawer (10), so that when the fan bracket drawer (10) is in the insertion position, the front wiring section (70) is freely accessible from the access side (16), but does not infringe on the space of the fan bracket drawer (10) when the fan bracket drawer (10) is removed from the housing (2) and inserted into the housing, - one or more quick electrical plug-socket connectors (71) for connecting the cables of the front wiring path (70) with the cables of the internal wiring path (72) extending in the fan wiring channel (37) of the fan bracket drawer (10), - a first rear wiring segment (74) and a second rear wiring segment (75), both of which are constrained to the fixed support structure (15) and extend on a side of the fan bracket drawer (10) opposite to the approach side (16) and extend spaced apart from each other on two opposite lateral sides of the fan bracket drawer (10).

21. A heat pump (78) comprising an outdoor unit (1) according to any one of the preceding claims.

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