HEAT PUMP

Description

FIELD OF THE INVENTION

The present invention relates to a heat pump of the type Heat pump comprising: a working circuit suitable for circulating a working fluid; a first heat exchanger and a second heat exchanger connected to the working circuit and suitable for exchanging heat of the working fluid, the first heat exchanger being suitable for exchanging heat with an external environment and comprising a finned structure, connected to the working circuit and ventilation means suitable for increasing the heat exchange of the external environment with the finned structure, a control unit of electronic type, configured to actuate and regulate the operation of the heat pump, a support structure suitable for supporting and containing at least part of the working circuit, the first heat exchanger and the control unit, the support structure comprising a first chamber, a second chamber and a third chamber, the chambers being reciprocally separated and being separated from the external environment by first partition walls, the finned structure and the ventilation means being contained in the first chamber, the first chamber comprising a first opening open to the external environment

DESCRIPTION OF THE PRIOR ART

The object of the present invention is a heat pump which is mainly applied in large commercial buildings and the like.

Installed heat pumps located outside the buildings are currently known. Heat pumps, used, for example, to vary indoor room temperatures and/or to produce domestic hot water, are devices that, either directly or via a carrier fluid, are capable of supplying thermal energy to a load so that the latter reaches a predetermined temperature value. They are typically placed near or on the roofs or exterior walls. In fact, heat pumps must be able to convey heat between indoor and outdoor environments.

Heat pumps require a refrigerant that performs the function of transporting heat, realizing the desired heat exchange between the outside and the inside, and carrying out the state transitions necessary to implement the refrigeration cycle. Said refrigerant is contained in an airtight refrigerant circuit.

The fluids chosen to play the role of heat transport must meet certain physical requirements so that they can efficiently perform the heat transport function.

Specifically, refrigerants must have a low boiling temperature, have the ability to liquefy at low pressures, have a low vapor volume, and possess a stable chemical structure. Fluids that meet these requirements can be propane, hydrofluorocarbons, halogenated hydrofluorocarbons, and halogenated hydrofluoroolefins. CFCs (chlorofluorocarbons) and HCFCs (halogenated hydrochloro fluorocarbons) also meet the requirements but are banned because of their polluting effects on the atmosphere.

Propane is among the most widely used natural refrigerants because of its reduced environmental impact compared to fluorinated refrigerants.

In temperature control devices, refrigerant is circulated within the circuit of a heat pump.

It is common in the known art to try to limit the presence of trigger sources or to render such sources harmless. Components known as ATEX, i.e., suitable for safe operation in potentially explosive environments, are commonly used for this task. Still, in other known solutions a physical separation impermeable to the flammable coolant is created around components that may be a source of ignition.

In a device such as a heat pump, said ignition sources are at least partly represented by sparkling components of electronic boards, power electronics elements that reach high temperatures, et similia. The known art described above has some significant drawbacks.

In particular, the use of flammable refrigerants such as propane can lead to the formation of fires and explosions if conditions of refrigerant concentration in an environment, such as due to a leak from the refrigerant circuit, and/or if the presence of ignition sources create a suitable environment.

Again, with regard to known-art solutions that involve physically separating, i.e., by means of physical walls impermeable to the coolant, the sparking components, this poses the risk of overheating since the environment around these components is also insulated at the same time. This type of solution of prior art is typically fitted with liquid cooling systems with dedicated circuits and costs for this purpose. Finally, the use of components suitable for working in hazardous environments, commonly referred to as ATEX, represents an additional cost to the company.

SUMMARY OF THE INVENTION

In this situation, the technical task underlying this invention is to devise a heat pump capable of substantially overcoming at least part of the aforementioned drawbacks. Within this technical task, it is an important aim of the invention to obtain a safer heat pump that can reduce hazardous situations.

The purpose of this invention is to reduce hazardous situations due to leakage of flammable refrigerant without employing ATEX components.

Again, one purpose of the present invention is to minimize the use of ATEX components for reduction of risk due to flammable refrigerant leakage.

Still, an important purpose of the present invention is to provide for a heat pump in which the provision for securing electronic components also allows for proper dissipation of the heat produced by said components.

The specified technical task and purposes are achieved by a heat pump comprising: a working circuit suitable for circulating a working fluid; a first heat exchanger and a second heat exchanger connected to the working circuit and suitable for exchanging heat of the working fluid, the first heat exchanger being suitable for exchanging heat with an external environment and comprising a finned structure, connected to the working circuit and ventilation means suitable for increasing the heat exchange of the external environment with the finned structure, a control unit of electronic type, configured to actuate and regulate the operation of the heat pump, a support structure suitable for supporting and containing at least part of the working circuit, the first heat exchanger and the control unit, the support structure comprising a first chamber, a second chamber and a third chamber, the chambers being reciprocally separated and being separated from the external environment by first partition walls, the finned structure and the ventilation means being contained in the first chamber, the first chamber comprising a first opening open to the external environment; the at least part of the working circuit is located in the third chamber, the third chamber includes at least one escape opening on the walls surrounding it so as to connect, in fluid passage connection, the chamber and the external environment, the escape opening being arranged in the lower part of the chamber, the second chamber comprises a first sub-chamber and a second sub-chamber, the sub-chambers being reciprocally separated by second partition walls, the first sub-chamber comprising the control unit, the second sub-chamber comprising at least a second opening on the external environment and a third opening on the first chamber so that the ventilation means force air to flow also between the second opening and the third opening through the second sub-chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of the invention are clarified below by a detailed description of preferred embodiments of the invention, with reference to the attached drawings, wherein:

FIG. 1 shows a top view of a heat pump according to the invention;

FIG. 2 shows a top view with cross-section details of a heat pump according to the invention;

FIG. 3 shows a cross-section view of a heat pump according to the invention; and

FIG. 4 shows a detail of a heat pump according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In this document, the measurements, values, shapes, and geometric references (such as perpendicularity and parallelism), when associated with words like “about” or other similar terms such as “approximately” or “substantially”, should be understood as allowing for measurement errors or inaccuracies due to production and/or manufacturing errors and, especially, minor deviations from the value, size, shape, or geometric reference with which they are associated. For example, such terms, when associated with a value, preferably indicate a deviation not exceeding 10% of the value itself.

Moreover, terms such as “first”, “second”, “upper”, “lower”, “main”, and “secondary” when used do not necessarily identify an order, priority of relation, or relative position but may simply be used to more clearly distinguish different components from one another.

Unless otherwise specified, as inferred from the following discussions, terms such as “processing”, “computing”, “determining”, “computation”, or similar should be understood as referring to the action and/or processes of a computer or similar electronic computation device that manipulates and/or transforms data represented as physical quantities, such as electronic magnitudes of records of a computing system and/or memories, into other data similarly represented as physical quantities within computer systems, records, or other information storage, transmission, or display devices.

Unless otherwise indicated, the measurements and data reported in this text are to be considered as performed in International Standard Atmosphere ICAO (ISO 2533:1975).

With reference to the Figures, the heat pump according to the invention is generally denoted by reference number 1. It may be, for example, a heat pump used for domestic utilities or for buildings such as warehouses or in general, buildings for industrial activities.

Heat pump 1 includes a working circuit 2. It is suitable for circulating a working fluid 2a. In fact, the working circuit 2 may include piping that allows the working fluid to circulate so that it can carry out heat exchanges and convey heat between different rooms.

In particular, working fluid 2a preferably includes propane. It is a working fluid particularly suitable for enabling heat exchange; in fact, it is typically used as a refrigerant fluid. It possesses characteristics such as a low boiling temperature, is able to liquefy at low pressures, has a low vapor volume and a stable chemical structure.

Alternatively, working fluid 2a may include one of your choice of hydrofluorocarbons, halogenated hydrofluorocarbons, and halogenated hydrofluoro olefins. In particular, the solution according to the present invention is advantageous in any case of using refrigerant fluid with any flammability characteristic such as A2L, A2, A3, B2L, B2, B3 and the like.

Heat pump 1 one a first heat exchanger 3 and a second heat exchanger 4. They are connected to the working circuit 2. Therefore, the working fluid 2a circulates at both the first exchanger 3 and the second exchanger 4. Exchangers 3, 4 are designed to allow heat exchanges of the working fluid 2a. It can evaporate within one of the exchangers by absorbing heat and condense in the other exchanger by transfering heat. For example, the first exchanger 3 can function as a condenser, then as an exchanger in which the working fluid 2a condenses transferring heat, and the second exchanger 4 as an evaporator, then as an exchanger in which the working fluid 2a evaporates absorbing heat.

In this regard, working circuit 2 preferably includes a lamination valve. In this way, a pressure drop of the working fluid 2a in the liquid state at the outlet of the condenser, its evaporation and a consequent decrease in the temperature of the working fluid 2a when it flows into the inlet of the evaporator can be realized.

In addition, working circuit 2 preferably includes a compressor 20. It allows increasing the pressure and temperature of the working fluid 2a in the gaseous state at the evaporator outlet and condenser inlet.

In detail, the first exchanger 3 is capable of exchanging heat with an external environment 10. It can be an outdoor environment, or a large environment within a large structure or building.

The first exchanger 3 includes a finned structure 35. They are connected to the working circuit 2. In fact, the finned structure 35 performs the function of promoting heat exchange between the working circuit 2 and the external environment 10 by promoting the passage of air. In addition, the finned structure 35 can perform a protection function for the portion of the working circuit 2 connected to the first exchanger 3.

The first exchanger 3 includes a finned structure ventilation means 36. They are designed to increase the heat exchange of the external environment 10 with the finned structure 35. In fact, ventilation means 36 realize a flow of air that promotes heat exchange. For example, ventilation means 36 can be fans.

Heat pump 1 includes a control unit 5. It may be electronic in nature. In particular, control unit 5 is advantageously configured to operate and regulate the operation of heat pump 1. It may consist of electronic boards operationally connected to the heat pump components, so as to control their operation and monitor parameters that enable the heat pump's operating status to be evaluated. It may also include electrical components such as a transformer and/or inverter or other.

Heat pump 1 includes a support structure 7. It is designed to support and contain at least part of the working circuit 2, the first heat exchanger 3 and the control unit 5. Support structure 7 preferably includes a first chamber 70. It mainly performs a support function for part of the working circuit 2 and the first exchanger 3. In fact, the finned structure 35 and ventilation means 36 are contained in the first chamber 70.

In addition, the first chamber 70 preferably includes a first opening 31. It is open to the external environment 10. The first opening 31 performs the function of facilitating heat exchanges between the working circuit 2 and the external environment 10. In some heat pump 1 configurations, there may be two or more first openings 31. Ventilation means 36 may preferably be placed near the first openings 31.

Support structure 7 includes a second chamber 71. In particular, control unit 5 is located in the second chamber 71. The first chamber 70 and the second chamber 71 can be mutually separated and separated from the external environment 10 by first partition walls 74. For example, the first chamber 70 and the second chamber 71 can be arranged next to each other and separated by a single first partition wall 74.

Advantageously, the second chamber 71 includes at least a second opening 710 on the external environment 10. It can then be placed in a first partition wall 74 separating the second chamber 71 from the external environment 10. In addition, the second chamber 71 advantageously includes a third opening 711 on the first chamber 70. The third opening 711 can be placed in a first partition wall 74 separating the first chamber 70 from the second chamber 71.

This placement of the second opening 710 and the third opening 711 causes the ventilation means 36 to force air flow also between the second opening 710 and the third opening 711 through the second chamber 71.

Therefore, the air flow realized by means of the ventilation means 36 in the vicinity of the first openings 31 means that, in addition to facilitating the heat exchange between the working circuit 2 and the external environment 10, it can also realize an air flow entering the second opening 710 from the external environment 10, passing inside the second chamber 71 and exiting from the third opening 711, passing through the first chamber 70 and exiting the first chamber 70 by means of at least the first opening 31 located near the second chamber 71.

Again, alternatively, in case said chamber 70 included at least two ventilation means 36, said third opening 711 is in fluid passage connection with only one of said at least two ventilation means 36. Advantageously, this feature makes it possible to adjust the airflow between openings 710, 711 independently of the air flow through battery 35.

In this way, the control unit 5 can exchange heat with the external environment 10 efficiently by means of an air flow.

In this regard, the control unit 5 preferably includes a first heat sink 50. It can be an element of high thermal conductivity, such as a finned element, preferably made of aluminum or copper. In particular, it performs the function of making heat exchanges with the surrounding environment more efficient. Therefore, passing an air flow near the first heat sink 50 causes a rapid heat exchange to take place between the heat sink and the air flow inside the second chamber 71 so as to cool the control unit 5. More specifically and advantageously, the second chamber 71 includes a first sub-chamber 71a and a second sub-chamber 71b. Sub-chambers 71a and 71b can be mutually separated by second partition walls 76. In particular, the first sub-chamber 71a may include control unit 5. The second sub-chamber 71b may include the first heat sink 50, the second opening 710, and the third opening 711. Therefore, the incoming air flow in the second opening 710 passes inside the second sub-chamber 71b, hitting the first heat sink 50, and then exits through the third opening 711. In this way, heat exchanges from control unit 5 take place by means of the first heat sink 50, the latter being located in the second sub-chamber 71b. Heat exchange in control unit 5 occurs only by means of the first heat sink 50. In this configuration of heat pump 1, therefore, control unit 5 is, in the event of a refrigerant leakage, advantageously not directly affected by a flow of air and refrigerant.

Preferably, second opening 710 and third opening 711 can be placed in a pair of parallel first partition walls 74, respectively. Therefore, the input direction into the second sub-chamber 71b and the output direction from the second sub-chamber 71b are parallel. In detail, the second opening 710 and the third opening 711 are preferably misaligned. In this way, the flow of air passing inside the second sub-chamber 71b is diverted by passing near the first heat sink 50 and then diverts again to exit through the third opening 711.

Consequently, preferably, the air reaching the heat sink is outside air, not processed by batteries.

In addition, preferably, the second sub-chamber 71b forms a channel having essentially an L-shape, and the two sub-chambers 71a and 71b are separated by a pair of second partition walls 76 arranged so as to be non-parallel and preferably substantially perpendicular to each other. The first heat sink can be placed along the second of the two second partition walls 76 that the air flow encounters as it passes inside the second sub-chamber 71b. The air flow, in this way, will be optimized to more efficiently invest the first heat sink 50. In addition, air flow is advantageously established by taking advantage of the movement of the ventilation means 36 present in the first chamber 70, without having to insert additional ventilation means to achieve flow.

Preferably the first chamber 70 has a tower shape, preferably trapezoidal, and the second chamber 71 is a longitudinal extension of the first chamber 70.

Support structure 7 includes a third chamber 72. It is separated from the second chamber 71 by first partition walls 74. In particular, the second chamber 71 and the third chamber 72 can be separated by a first partition wall 74. In addition, the third chamber 72 is separated from the external environment 10 by first partition walls 74. In fact, at least part of the working circuit 2 is located in the third chamber 72.

The third chamber 72 is also preferably below the first and/or second chambers 70 and 71.

Also preferably according to the latter embodiment, within support structure 7, along a vertical direction starting from the bottom the components are arranged in the following order: third chamber 72, opening 710 and second chamber 71. Advantageously, this arrangement allows any propane leaks from the third chamber 72 to be drawn in through said opening 710, and then through said second sub-chamber 71b, before they can come into contact with the electronic components contained in the first sub-chamber 71a.

First partition walls 74 may preferably define at least a first impermeable wall 74b. It is designed to separate the second chamber 71 from the third chamber 72. In addition, the first impermeable wall 74b is impermeable to gases. In this way, safety conditions can be further improved by preventing any leaks of working fluid 2a gas from reaching the control unit 5.

Preferably, compressor 20 is placed inside the third chamber 72.

The third chamber 72 is preferably in fluid passage connection with the external environment. Said fluid passage connection is preferably made in the lower part of the third chamber 72. More preferably, it is achieved by one or more escape openings 75 on the walls 74 and preferably on the lower part, and preferably in the lower wall 74a of the chamber 72. Openings 75 may include one or more holes 75a preferably in said lower wall 74a of chamber 72. Thus, a leakage of propane is released in a lower zone of structure 7, because propane is heavier than ambient air.

Alternatively, or in addition, escape openings 75 include a fourth opening 75b. It is preferably placed in one of the first partition walls 74. This opening may include a grid. Still preferably, said opening 75b is placed on a wall 74 opposite to the wall including said opening 710. Advantageously, in this embodiment, a refrigerant leak is directed away from the 710 intake of chamber 71b.

In addition or alternatively, there are auxiliary ventilation means 76 suitable for forcing an air flow preferably of ATEX type or otherwise suitable for use in explosive environments. Specifically, auxiliary means 76 are placed at the fourth opening 75b. In this way, any gaseous leaks originating inside the third chamber 72 can be vented to the external environment 10, preventing stagnation inside and consequent risks of fire or explosion.

The second exchanger 4 is preferably located in the external environment 10 and inside the support structure 7. In this way, it can transfer heat with an external water circuit 8. In some configurations, the second exchanger 4 may be a plate exchanger within which a portion of the water circuit 8 is inserted so as to realize a heat exchange between the second exchanger 4 and the water circuit 8. The latter may also include a tank suitable for holding water, which can be piped to additional rooms. For example, piped water can be used for domestic or industrial users. Alternatively, the second exchanger 4 can be placed inside an environment with which heat exchange is carried out, such as domestic environments or, more generally, indoor environments in buildings. In these applications, heat pump 1 is used to regulate indoor room temperature.

In some heat pump 1 configurations, the support structure 7 is preferably placed on a floor. It may be, for example, a road surface or the floor of a terrace.

Support structure 7 can define a first portion 7a and a second portion 7b. Specifically, the second portion 7b is in contact with the ground and the first portion 7a is in contact with the second portion 7b. Therefore, the first portion 7a is distanced from the ground, since the second portion 7b is interposed between the ground and the first portion 7a.

The first portion 7a preferably includes the first chamber 70 and the second chamber 71. The second portion 7b includes the third chamber 72 and a housing 73. It is an open housing connected to the external environment 10. It is intended to support the first chamber 70. In fact, it may include a support structure, which allows the first chamber 70 to be supported. In addition, housing 73 can be separated from the third chamber 72 by a first partition wall 74. Within this latter first partition wall 74 there may be the fourth opening 75b. Water circuit 8, second exchanger 4, and tank 20 can be housed inside housing 73. In detail, a water tank and water circuit pump 8 can be housed inside housing 73.

This placement of chambers 70-72 and housing 73 allows the support structure 7 of heat pump 1 to be more compact and promotes the operation of the refrigerant leakage safety system that is the subject of the invention.

The operation of the heat pump 1 previously described in structural terms is as follows.

During regular operation of the heat pump 1 a flow of air entering the second opening 710 from the external environment 10 is conveyed into the second chamber 71. Specifically, it is conveyed inside the second sub-chamber 71b, and then passes through the third opening 711. The air flow cools the first heat sink 50. In turn, the first heat sink 50 exchanges heat and cools the control unit 5, contained within the first sub-chamber 71a.

The air flow, through the third opening 711 passes inside the first chamber 70 and exits to the external environment 10 through the first opening 31. Ventilation means 36 convey the air flow in the described direction.

Part of working circuit 2 is contained in the third chamber 72 separated from the second chamber 71. No portion of working circuit 2 passes inside the second chamber 71. The working circuit 2 conveys the working fluid 2a to the first exchanger 3 and to the second exchanger 2, so as to realize a net heat exchange between the external environment 10 and, depending on the application of the heat pump 1, the water contained in the water circuit 8 or an indoor environment.

The third chamber 72 can circulate air through the fourth opening 74a to vent any working fluid 2a gas leaks.

The heat pump 1 according to the invention achieves important advantages.

In fact, the separation of the portion of the working circuit 2 from the second chamber 71 in which the control unit 5 is contained and the arrangement of chambers 72, 71 with respect to the opening 710, makes it possible to reduce the risks associated with any leakage of working fluid 2a gas in the event of breakage or malfunction of the working circuit 2. In fact, this prevents the gaseous working fluid 2a (typically a flammable gas) from giving rise to fires as a result of contact with any sparks originating in the control unit 5.

The presence of the fourth opening 75b in the third chamber 72 means that, in the event that gas escapes from the working circuit 2, it can be vented outside the support structure 7 and, thus, into the external environment 10.

Heat pump 1 also has the advantage of making heat transfer from the control unit 5 to the external environment 10 more efficient. This transfer is made efficient through the connection between the sub-chamber in which the heat sink connected to the control unit 5 is located and the first chamber 70 in which the ventilation elements 36 are located to convey air from the external environment. This advantageously realizes air flow originating from the movement of ventilation elements without having to add additional special ventilation elements. In addition, the geometry of the sub-chamber into which air flows when it is drawn from the outside causes the air flow to make heat exchanges with the heat sink more efficient. Finally, the air flow does not directly affect the control unit 5, which is cooled only by means of the first heat sink.

The invention is subject to variations within the scope of the inventive concept defined by the claims.

Within this scope, all details can be replaced by equivalent elements, and materials, shapes, and dimensions may be any.