Refrigerant fluid circuit comprising a reservoir bypass branch

Abstract

A refrigerant fluid circuit (2) includes a main branch (20) including a receiver (4), a compressor (3) and at least one first heat exchanger (31), the refrigerant fluid circuit (2) includes a first branch (21) and a second branch, the first branch (21) including at least one second heat exchanger (32), the second branch including at least one third heat exchanger (33), the refrigerant fluid circuit (2) including a bypass branch (25) starting at the second branch (22), and the refrigerant fluid circuit (2) including a control member (8) configured to control the flow of refrigerant fluid from the second branch (22) to the receiver (4) and / or to the bypass branch (25).

Description

[0001] The field of this invention is the field of heat treatment systems for heating or cooling spaces or components of a vehicle, particularly components of the vehicle's passenger compartment or powertrain. More particularly, the invention relates to a refrigerant fluid circuit included in such a heat treatment system.

[0002] Motor vehicles are currently equipped with refrigerant fluid circuits and heat transfer fluid circuits, both of which are used to facilitate heat treatment of various areas or components of the vehicle. In particular, such refrigerant fluid circuits are known for heat treatment of airflow delivered into the passenger compartment of a vehicle equipped with such a circuit.

[0003] In another application of this circuit, heat transfer fluid circuits are known to be used to cool components of a vehicle's powertrain, such as energy storage devices that supply energy to the motors that enable the vehicle to move. A refrigerant fluid circuit indirectly facilitates this cooling by applying heat to the heat transfer fluid circuit via at least one heat exchange between the two fluids. Therefore, when a heat treatment system is used during the drive phase, the heat treatment system supplies energy capable of cooling the energy storage device. To cool the heat transfer fluid, the refrigerant fluid circuit specifically includes a compressor and a receiver. The compressor compresses the refrigerant fluid in a gaseous state, and the receiver holds the refrigerant fluid in a liquid state, preventing the liquid refrigerant fluid from circulating through the compressor and damaging it.

[0004] When energy storage devices require very rapid recharging, the need to cool the heat transfer fluid to enable it to cool the energy storage device can increase dramatically. For this reason, the heat treatment system may include two heat exchangers to enhance the cooling capacity of the heat transfer fluid via refrigerant fluid. One heat exchanger is connected to a reservoir, and the other bypasses the reservoir to maintain the circulating charge within the refrigerant fluid loop.

[0005] To limit production costs, it may still be necessary to limit production to a single heat exchanger, designed to perform cooling of the energy storage device and ensure heat exchange between two fluid circuits. In this configuration, and depending on the operating mode of the refrigerant fluid circuit, the refrigerant fluid at the output of this heat exchanger cannot be completely directed to the receiver nor completely bypassed, in order to maintain the circulation charge while preserving the lifespan of the components of the refrigerant fluid circuit.

[0006] This invention overcomes this drawback by providing a refrigerant fluid circuit for a heat treatment system. The refrigerant fluid circuit includes a main branch that originates at a first confluence point and terminates at a first branch point, and includes at least one reservoir, a compressor, and at least a first heat exchanger. The refrigerant fluid circuit also includes at least a first branch and a second branch, both originating at the first branch point and terminating at the first confluence point. The first branch includes at least a second heat exchanger, and the second branch includes at least a third heat exchanger. The invention is characterized by including a bypass branch that originates at a second branch point located on the second branch, downstream of the third heat exchanger, and terminates at a second confluence point located on the main branch, downstream of the reservoir and upstream of the compressor.

[0007] With this circuit, depending on the operating mode of the refrigerant fluid circuit, the refrigerant fluid, after being heat-treated in the third heat exchanger, can be guided to or bypass the receiver. This arrangement allows for the maintenance of refrigerant fluid circulation while extending the normal operation of the circuit components, and more particularly, extending the operation of the compressor.

[0008] The compression equipment is responsible for the refrigerant fluid in the circulation loop, especially by compressing the gaseous refrigerant fluid under high pressure, which also has the effect of increasing its temperature.

[0009] Each of the heat exchangers arranged in the refrigerant fluid circuit is involved in at least the heat exchange of the refrigerant fluid. Depending on the operating mode of the circuit, the refrigerant fluid can therefore release or absorb heat energy through these heat exchanges.

[0010] The receiver is positioned upstream of the compressor relative to the refrigerant fluid circulation direction. For example, the receiver can be in the form of a tank, which has the function of retaining any portion of the refrigerant fluid in liquid form after it has circulated in the refrigerant fluid loop. Therefore, the receiver prevents the refrigerant fluid in liquid form from circulating as far as the compressor, since the compressor cannot operate on the refrigerant fluid in liquid form.

[0011] The first and second branches each include at least one heat exchanger. The second heat exchanger located on the first branch participates in the heat exchange that leads to the cooling of the vehicle. The third heat exchanger located on the second branch indirectly participates in the heat treatment of one or more components of the vehicle that are prone to releasing heat during its operation (e.g., the vehicle's electric motor's energy storage device).

[0012] According to one feature of the invention, the refrigerant fluid circuit includes a control element configured to manage the circulation of refrigerant fluid from a second branch to a receiver and / or to a bypass branch. The control element allows determination of the distribution of refrigerant fluid circulating in the second branch that is directed to or bypasses the receiver. Therefore, this control element is parameterizable to modify the refrigerant fluid distribution, and to do so according to the operating mode of the refrigerant fluid circuit.

[0013] According to one feature of the invention, the control element is disposed on the second branch, downstream of the third heat exchanger. Advantageously, the control element is substantially disposed in the region of the refrigerant fluid circuit, in which the refrigerant fluid circulating in the second branch circulates to the receiver and / or circulates within the bypass branch.

[0014] According to one feature of the invention, the refrigerant fluid circuit is configured to circulate all the refrigerant fluid circulating in the first branch to a receiver. Depending on the cooling requirements of the vehicle's passenger compartment, the proportion of liquid refrigerant fluid at the output of the second heat exchanger may be large. Advantageously, the refrigerant fluid circulating in the first branch thus systematically passes through the receiver, allowing the liquid refrigerant fluid to be stored and retained in the receiver.

[0015] According to one feature of the invention, the first heat exchanger is configured to perform heat exchange between the refrigerant fluid circulating in the main branch and the external airflow to the passenger compartment of the vehicle. To be positioned in the path of the external airflow, the first heat exchanger may, for example, be located at the front end of the vehicle. Depending on the operating mode of the refrigerant fluid circuit, the first heat exchanger allows the refrigerant fluid to be cooled by the external airflow. According to another operating mode, the first heat exchanger may also allow the external airflow to be cooled by the refrigerant fluid.

[0016] According to one feature of the invention, the second heat exchanger is configured to perform heat exchange between the refrigerant fluid circulating in the first branch and the interior airflow intended to be delivered into the passenger compartment of the vehicle. Thus, the interior airflow directly cools the vehicle's passenger compartment by pre-cooling the refrigerant fluid circulating in the first branch and, more particularly, through the second heat exchanger. For this reason, the second heat exchanger can be integrated, for example, within ventilation, heating, and / or air conditioning systems, ensuring that the interior airflow circulates in a recirculating manner to cool or heat the passenger compartment depending on its operating mode.

[0017] According to one feature of the invention, the third heat exchanger is configured to perform heat exchange between the refrigerant fluid circulating in the second branch and the heat transfer liquid circuit. The heat transfer liquid directly cools the aforementioned energy storage device. By cooling the energy storage device, the heat transfer liquid recovers thermal energy. Then, during the heat exchange between the refrigerant fluid and the heat transfer liquid occurring within the third heat exchanger, this thermal energy is recovered by the refrigerant fluid circulating in the second branch.

[0018] According to one feature of the invention, the refrigerant fluid circuit includes an expansion member disposed upstream of the first heat exchanger. The expansion member allows the refrigerant fluid to expand before it passes through the heat exchanger. This expansion of the refrigerant fluid allows for a reduction in its pressure and temperature, thereby enabling the absorption of thermal energy. Depending on the operating mode of the refrigerant fluid circuit, the expansion member has specific characteristics that allow the refrigerant fluid to circulate without necessarily expanding it.

[0019] According to one feature of the invention, the refrigerant fluid circuit includes an expansion element disposed upstream of the second heat exchanger. The expansion element allows for the reduction of the pressure and temperature of the refrigerant fluid to cool the internal airflow via the second heat exchanger.

[0020] According to one feature of the invention, the refrigerant fluid circuit includes an expansion device disposed upstream of the third heat exchanger. The expansion device allows for a reduction in the pressure and temperature of the refrigerant fluid to cool the heat transfer liquid circulating in the heat transfer liquid circuit via the third heat exchanger.

[0021] According to one feature of the invention, the refrigerant fluid circuit may include a fourth heat exchanger comprising a first section disposed on a first branch upstream of the expansion element and a second section disposed on a main branch downstream of the receiver and upstream of the second confluence point. The fourth heat exchanger is configured to perform heat exchange between the refrigerant fluid circulating in the first branch and the refrigerant fluid circulating in the main branch. A bypass branch is configured to allow refrigerant fluid circulation such that the refrigerant fluid bypasses the fourth heat exchanger and the receiver. In other words, the fourth heat exchanger is located inside the refrigerant fluid circuit and ensures heat exchange between the two portions of the refrigerant fluid circulating in two different parts of the circuit. The fourth heat exchanger simultaneously pre-cools the refrigerant fluid circulating in the first branch and heats the refrigerant fluid in the main branch at the outlet of the receiver.

[0022] Pre-cooling of the refrigerant fluid circulating in the first branch allows for more efficient cooling via the expansion element before it circulates through the second heat exchanger. Furthermore, increasing the temperature of the refrigerant fluid downstream of the receiver allows any liquid phase of the refrigerant fluid that may form during circulation between the receiver and the compressor to evaporate. Therefore, the refrigerant fluid arrives at the compressor in a completely gaseous state.

[0023] According to one feature of the invention, the refrigerant fluid circuit may include a fifth heat exchanger comprising a first section disposed on a second branch upstream of an expansion device and a second section disposed on a bypass branch. The fifth heat exchanger is configured to perform heat exchange between the refrigerant fluid circulating in the second branch and the refrigerant fluid circulating in the bypass branch. Following the same principle as the fourth heat exchanger, the fifth heat exchanger pre-cools the refrigerant fluid circulating in the second branch to create more efficient expansion at the expansion device and thus better cooling before passing through the third heat exchanger. Conversely, heating the refrigerant fluid circulating in the bypass branch allows for the evaporation of any liquid phase of the refrigerant fluid that may form during circulation in the bypass branch, and this occurs before the refrigerant fluid is compressed by the compression device.

[0024] According to one feature of the invention, the refrigerant fluid circuit may include a sixth heat exchanger disposed on the main branch, downstream of the compressor and upstream of the first heat exchanger, and configured to perform heat exchange between the refrigerant fluid circulating in the main branch and the heat transfer fluid. Since this heat exchange occurs downstream of the compressor, the refrigerant fluid circulates through the sixth heat exchanger at an elevated temperature. Therefore, this heat exchange allows for the pre-cooling of the refrigerant fluid. According to one example, the heat exchange may be achieved using a heat transfer liquid circulating in the heat transfer fluid circuit. In this case, the heat exchange allows for the preheating of the heat transfer liquid for the purpose of heating the passenger compartment. According to another example, the heat exchange may be achieved using an internal airflow to directly heat the passenger compartment. In this case, the sixth heat exchanger is integrated within ventilation, heating, and / or air conditioning facilities, like a second heat exchanger.

[0025] According to one feature of the invention, the refrigerant fluid circuit may include a third branch that originates at a third branch point on the main branch, downstream of the sixth heat exchanger and upstream of the first heat exchanger, and terminates at a third convergence point on the main branch, downstream of the first heat exchanger and upstream of the first branch point. The third branch includes a first valve configured to manage the circulation of refrigerant fluid within the third branch. In other words, the third branch allows the refrigerant fluid to bypass the first heat exchanger and the expansion member. The purpose of the third branch is to circulate the refrigerant fluid as far as the expansion device and the third heat exchanger, where the refrigerant fluid has not previously expanded via the expansion member. Therefore, when the first valve is in the open position, the refrigerant fluid circulates within both the main branch and the third branch, while when the first valve is in the closed position, the refrigerant fluid circulates only within the main branch.

[0026] According to another feature of the invention, the refrigerant fluid circuit may include a fourth branch that originates at a fourth branch point located on the main branch, downstream of the first heat exchanger and upstream of the third junction point, and terminates at the first junction point, or terminates on the main branch downstream of the first junction point and upstream of the receiver. The fourth branch includes a second valve configured to manage the circulation of refrigerant fluid within the fourth branch. The fourth branch allows refrigerant fluid to reach the receiver directly after passing through the first heat exchanger, for example, during an operating mode for heating the passenger compartment of a vehicle. For this purpose, the refrigerant fluid passing through the first heat exchanger must expand via an expansion member. Depending on its location, the second valve allows or disallows the circulation of refrigerant fluid in the fourth branch.

[0027] Advantageously, the first and second valves open simultaneously, allowing the refrigerant fluid to circulate in both the third and fourth branches. In this configuration, the refrigerant fluid is divided into two parts at the third branch point. The first part expands through the expansion member, passes through the first heat exchanger, and then circulates through the fourth branch to the heat accumulator, while the second part bypasses the expansion member and the first heat exchanger to be supplied to the third heat exchanger via pre-expansion by the expansion device.

[0028] According to one feature of the invention, the control element can be a variable-opening valve disposed on a second branch, downstream of the second branch point and upstream of the first junction point, or disposed on a bypass branch, downstream of the second branch point and upstream of the second junction point. After passing through the third heat exchanger, the refrigerant fluid can circulate to the receiver or circulate within the bypass branch. The variable-opening valve allows for the management of the amount of refrigerant fluid circulating to the receiver. Therefore, depending on the degree of opening of the variable-opening valve, the distribution of refrigerant fluid circulating to or around the receiver can be implemented. If the variable-opening valve is positioned on the second branch, a lower degree of opening of the variable-opening valve results in a higher proportion of refrigerant fluid circulating within the bypass branch. If the variable-opening valve is positioned on the bypass branch, a lower degree of opening of the variable-opening valve results in a lower proportion of refrigerant fluid circulating within the bypass branch.

[0029] According to one feature of the invention, the control element may be a three-way valve disposed at the second branch point. Therefore, all refrigerant fluid that has passed through the third heat exchanger passes through the three-way valve. The three-way valve is parameterized to manage the distribution of refrigerant fluid circulating to the receiver or in the bypass branch.

[0030] The present invention also covers a method for controlling a refrigerant fluid circuit as claimed in any of the preceding claims, during which:

[0031] - In the mode used to cool the passenger compartment of the vehicle, the control components are adjusted so that all refrigerant fluid circulates in the bypass branch.

[0032] - In the mode used to heat the passenger compartment of the vehicle, the control components are adjusted to determine the proportion of refrigerant fluid circulating to the reservoir and / or in the bypass branch.

[0033] When the refrigerant fluid circuit operates according to the mode for cooling the passenger compartment of the vehicle, the refrigerant fluid circulates specifically in the first branch to cool the passenger compartment. As indicated above, all the refrigerant fluid circulating in the first branch reaches the receiver. In parallel, the refrigerant fluid also circulates in the second branch for heat treatment via the third heat exchanger. To limit pressure drop and prevent the compressor from overworking due to an excessive proportion of refrigerant fluid passing through the receiver, all the refrigerant fluid circulating in the second branch at the output of the third heat exchanger is directed to a bypass branch via a control mechanism.

[0034] According to a feature of this method, in the mode used to heat the passenger compartment of the vehicle, the refrigerant fluid recovers heat energy by passing through a third heat exchanger. In this mode, the refrigerant fluid therefore does not circulate in the first branch. Therefore, circulation is only achieved in the second branch. Since the refrigerant fluid cannot completely bypass the reservoir, it must circulate at least partially in the second branch to the reservoir. Thus, the control components are adapted to distribute the refrigerant fluid in a manner suitable for the operating mode.

[0035] Further features and advantages of the invention will become more apparent from the following description and from the accompanying illustrative drawings, which are given as non-limiting embodiments, in which:

[0036] Figure 1 A first embodiment of the refrigerant fluid circuit according to the present invention is shown.

[0037] Figure 2 A second embodiment of the refrigerant fluid circuit is shown.

[0038] Figure 3 The circulation of refrigerant fluid within a second embodiment of a refrigerant fluid circuit according to a pattern for cooling the passenger compartment of a vehicle is shown.

[0039] Figure 4 The circulation of refrigerant fluid within a second embodiment of a refrigerant fluid circuit according to a pattern for heating the passenger compartment of a vehicle is shown.

[0040] Figure 5 A second embodiment of a refrigerant fluid circuit including alternative control components is shown.

[0041] The terms upstream and downstream used in the following description relate to the circulation direction of the refrigerant fluid.

[0042] exist Figure 1 , Figure 2 and Figure 5 In the diagram, refrigerant fluid loop 2 is shown as a solid line. Figures 3 to 4 In the diagram, the portions through which the refrigerant fluid passes are shown with solid lines, and the portions where no refrigerant fluid circulates are shown with dashed lines. Furthermore, the circulation of the refrigerant fluid is indicated by arrows pointing in its direction. Regarding refrigerant fluid loop 2, the solid lines indicating fluid circulation also have different thicknesses. More specifically, thicker solid lines correspond to the portions where the refrigerant fluid circulates under high pressure, while thinner solid lines correspond to the portions where the refrigerant fluid circulates under low pressure.

[0043] The terms “first,” “second,” etc., used in the description are not intended to indicate hierarchical levels or to order the elements they accompany. These terms are used to distinguish the elements they accompany and are interchangeable without narrowing the scope of the invention.

[0044] Figure 1 A refrigerant circuit 2 according to a first embodiment is shown without indication of fluid circulation. The refrigerant fluid circuit 2 is configured to form part of a heat treatment system (e.g., within a vehicle). The refrigerant fluid may be, for example, a fluid of the R134a or R1234yf type.

[0045] The refrigerant fluid circuit 2 includes a main branch 20 extending from a first confluence point 45 to a first branch point 41. The first branch point 41, and all branch points presented below, correspond to the points where a branch splits into multiple branches. The first confluence point 45, and all confluence points presented below, correspond to the points where multiple branches merge into a single branch.

[0046] The main branch 20, in the direction of refrigerant fluid circulation, sequentially includes a receiver 4, a compressor 3, an expansion member 37, and a first heat exchanger 31. The compressor 3 circulates the gaseous refrigerant fluid. The refrigerant fluid is brought to high pressure and high temperature before circulating downstream of the compressor 3.

[0047] The compressor 3 can only compress refrigerant fluid in gaseous form. For this reason, the receiver 4 is located upstream of the compressor 3. The receiver 4 allows any liquid portion of the refrigerant fluid circulating in the main branch 20 between the first confluence point 45 and the receiver 4 to be retained. Therefore, only the gaseous form of the refrigerant fluid circulates from the receiver 4 to the compressor 3.

[0048] The first heat exchanger 31 is located downstream of the compression device 3. An expansion member 37 is disposed upstream of the first heat exchanger 31 and downstream of the compression device 3. The expansion member 37 allows the refrigerant fluid to expand after it has been brought to high pressure by the compression device 3. However, the expansion member 37 also has the capability to allow the refrigerant fluid to pass through without expanding. Therefore, the refrigerant fluid can pass through the first heat exchanger 31 at high or low pressure, depending on the operating mode of the refrigerant fluid circuit 2.

[0049] The first heat exchanger 31 is configured to perform heat exchange between the refrigerant fluid passing through it and the external airflow 5 to the passenger compartment of the vehicle. For this reason, the first heat exchanger 31 may be positioned, for example, at the front of the vehicle, so as to be arranged in the path of the external airflow 5. The function of the first heat exchanger 31 depends on the operating mode of the refrigerant fluid circuit 2.

[0050] At the first branch point 41, the refrigerant fluid circuit 2 splits into a first branch 21 and a second branch 22. Each branch includes a heat exchanger and an expansion device located upstream of each of the heat exchangers. The expansion device is configured to meet the needs of the vehicle's heat treatment system.

[0051] The first branch 21 includes a second heat exchanger 32 and an expansion element 38 located upstream of the second heat exchanger 32. The second heat exchanger 32 is configured to perform heat exchange between a refrigerant fluid and the internal airflow 6 delivered to the passenger compartment of the vehicle. For this reason, the second heat exchanger 32 can be arranged within ventilation, heating, and / or air conditioning facilities (not shown). Thus, the second heat exchanger 32 allows the internal airflow 6 to be cooled, allowing it to be delivered into the passenger compartment for air conditioning. The expansion element 38 allows the refrigerant fluid to expand, causing it to pass through the second heat exchanger 32 at a low temperature to cool the internal airflow 6. The first branch 21 extends as far as the first convergence point 45. Therefore, all refrigerant fluid passing through the first branch 21 circulates as far as the receiver 4.

[0052] The second branch 22 includes a third heat exchanger 33 and an expansion device 39 disposed upstream of the third heat exchanger 33. The third heat exchanger 33 is configured to perform heat exchange between a refrigerant fluid and a heat transfer fluid circuit, partially shown in dashed lines. The heat transfer fluid, in particular, has the function of ensuring the thermal treatment (more specifically, cooling) of one or more electrical components of the vehicle (e.g., an energy storage device (not shown)). Therefore, the refrigerant fluid circulating through the third heat exchanger 33 has the function of indirectly cooling the energy storage device by recovering heat energy from the heat transfer fluid, allowing the heat transfer fluid to cool the energy storage device.

[0053] Like the first branch 21, the second branch 22 extends from the first branch point 41 to the first converging point 45. However, the second branch 22 includes a second branch point 42 located downstream of the third heat exchanger 33 and upstream of the first converging point 45. Figure 1 In the second branch point 42, a control element 8 in the form of a three-way valve 82 is included. This valve allows refrigerant fluid to be directed to the receiver 4 or to a bypass branch 25.

[0054] Bypass branch 25 allows a connection to be established between the second branch 22 and the compression device 3 by bypassing the reservoir 4. For this purpose, bypass branch 25 extends from the second junction point 42 to a second junction point 46 located on the main branch 20, downstream of the reservoir 4 and upstream of the compression device 3.

[0055] Therefore, the control component 8 can be remotely controlled to manage the distribution of refrigerant fluid from the output of the third heat exchanger 33 to the receiver 4 or the bypass branch 25. This distribution depends on the operating mode of the refrigerant fluid loop 2, which will be described in detail below. The ability to distribute refrigerant fluid leaving the third heat exchanger 33 to reach or bypass the receiver 4 allows for the preservation of refrigerant fluid recirculation and extends the service life of the compressor 3, which may be overused in the event of a drop in refrigerant fluid pressure.

[0056] Figure 2 A second embodiment of the refrigerant fluid circuit 2 is shown, which is more... Figure 1 The first embodiment shown is more complex. All matters concerning the structural similarities between the two embodiments will be referred to... Figure 1 The description.

[0057] exist Figure 2 In this configuration, the refrigerant fluid circuit 2 includes a fourth heat exchanger 34 and a fifth heat exchanger 35. These two heat exchangers are located inside the refrigerant fluid circuit. In other words, the two heat exchangers are configured to perform heat exchange between two parts of the refrigerant fluid circuit 2.

[0058] The fourth heat exchanger 34 includes a first section 61 located on the first branch 21, downstream of the first branch point 41 and upstream of the expansion element 38, and a second section 62 located on the main branch 20, downstream of the receiver 4 and upstream of the second confluence point 46. Therefore, the bypass branch 25 ensures that the refrigerant fluid circulating therein reaches the compressor 3 without passing through the receiver 4 and without circulating within the second section 62 of the fourth heat exchanger 34.

[0059] The fourth heat exchanger 34 allows the refrigerant fluid circulating in the first branch 21 to be pre-cooled before it expands via the expansion element 38. The fourth heat exchanger 34 also allows the refrigerant fluid circulating between the receiver 4 and the compressor 3 to be reheated, and thus evaporates any potential portion of the refrigerant fluid that has already condensed at the outlet of the receiver 4.

[0060] The fifth heat exchanger 35 includes a first section 63 located on the second branch 22, downstream of the first branch point 41 and upstream of the expansion device 39, and a second section 64 located on the bypass branch 25, downstream of the second branch point 42 and upstream of the second convergence point 46.

[0061] The fifth heat exchanger 35 allows the refrigerant fluid circulating in the second branch 22 to be precooled before it expands via the expansion device 39. The fifth heat exchanger 35 also allows the refrigerant fluid circulating in the bypass branch 25 to be reheated in order to evaporate any potential portion of the refrigerant fluid that may have condensed after leaving the third heat exchanger 33.

[0062] The refrigerant fluid circuit 2 also includes a sixth heat exchanger 36 installed on the main branch 20, downstream of the compressor 3 and upstream of the expansion member 37. The sixth heat exchanger 36 is configured to perform heat exchange between the refrigerant fluid and the heat transfer fluid 10. Figures 2 to 4 In this process, the heat transfer fluid 10 is a heat transfer liquid circulating within the heat transfer liquid loop 7. The heat exchange performed on the sixth heat exchanger 36 allows for the simultaneous pre-cooling of the refrigerant fluid (which is at a high temperature after being compressed by the compression device 3) and heating of the heat transfer liquid, for example, for the purpose of indirectly heating the passenger compartment of the vehicle.

[0063] The refrigerant fluid circuit 2 also includes a third branch 23, which originates at a third branch point 43 located on the main branch 20, downstream of the sixth heat exchanger 36. The third branch 23 extends as far as a third convergence point 47, located on the main branch 20, downstream of the first heat exchanger 31 and upstream of the first branch point 41.

[0064] Therefore, the third branch 23 allows refrigerant fluid to circulate from the compressor 3 to as far as the first branch point 41 without passing through the expansion member 37 and the first heat exchanger 31. To prevent the refrigerant fluid circulating in the third branch 23 from recirculating back to the first heat exchanger 31 once it reaches the third confluence point 47, the main branch 20 includes a check valve 53 downstream of the first heat exchanger 31 and upstream of the third confluence point 47. Furthermore, the third branch 23 includes a first valve 51 to allow or disallow refrigerant fluid circulation in the third branch 23.

[0065] The refrigerant fluid loop 2 finally includes a fourth branch 24, which originates at a fourth branch point 44 located on the main branch 20, downstream of the first heat exchanger 31 and upstream of the third confluence point 47, and terminates at the first confluence point 45. The fourth branch 24 includes a second valve 52 to allow or disallow the refrigerant fluid to circulate in the fourth branch 24.

[0066] Figure 3 The circulation of refrigerant fluid is shown according to a pattern for cooling the passenger compartment of a vehicle. This pattern for cooling the passenger compartment of a vehicle includes simultaneously cooling the passenger compartment and an electrical storage device for cooling the vehicle.

[0067] For this purpose, the refrigerant fluid is first circulated under high pressure and high temperature by the compression device 3, and then pre-cooled by the heat transfer liquid via the sixth heat exchanger 36.

[0068] The refrigerant fluid then circulates to the expansion member 37. Since the expansion member is fully open, the refrigerant fluid does not expand and passes through the first heat exchanger 31. Within the first heat exchanger 31, the refrigerant fluid is cooled by the external airflow 5.

[0069] The refrigerant fluid then circulates to the first branch point 41, where it splits into two parts. The first part circulates in the first branch 21 to participate in the cooling of the vehicle's passenger compartment, while the second part circulates in the second branch 22 to participate in the cooling of the electrical storage equipment.

[0070] A first portion of the refrigerant fluid is pre-cooled by circulating in the first section 61 of the fourth heat exchanger 34, then expands by the expansion element 38, and subsequently passes through the second heat exchanger 32. The expansion of the refrigerant fluid allows for a reduction in its pressure and temperature. Therefore, the refrigerant fluid passes through the second heat exchanger 32 at a low temperature to cool the internal airflow 6 passing through the second heat exchanger 32. The cooled internal airflow 6 is then directed to the vehicle's passenger compartment for air conditioning.

[0071] At the output of the second heat exchanger 32, the refrigerant fluid continues to circulate within the first branch 21 until it reaches the first confluence point 47, and then reaches the main branch 20 to the receiver 4. The entire first portion of the refrigerant fluid reaches the receiver 4. The receiver retains the potential liquid portion of the first portion of the refrigerant fluid, while the gaseous portion continues to circulate within the main branch 20 to the second section 62 of the fourth heat exchanger 34 before finally reaching the compression unit 3.

[0072] A second portion of the refrigerant fluid circulates in the second branch 22. This second portion is first pre-cooled by circulating in the first section 63 of the fifth heat exchanger 35, then expanded by the expansion device 39, and subsequently passes through the third heat exchanger 33. Like the expansion element 38, the expansion of the refrigerant fluid by the expansion device 39 allows for a reduction in its pressure and temperature.

[0073] The refrigerant fluid passes through the third heat exchanger 33 at a low temperature to exchange heat with the heat transfer fluid circulating in the heat transfer fluid circuit 7. The heat transfer fluid circuit 7 is configured to cool an energy storage device that may release heat that could damage it. Therefore, the heat transfer fluid is cooled by the refrigerant fluid via the third heat exchanger. The cold heat transfer fluid then cools the energy storage element (e.g., also via heat exchange), and thus the heat transfer fluid is at a high temperature after such a cooling operation. Therefore, the third heat exchanger 33 allows the heat transfer fluid to be cooled, enabling the heat transfer fluid to continuously cool the energy storage device.

[0074] After passing through the third heat exchanger 33, the refrigerant fluid reaches the second branch point 42, where a three-way valve 82, acting as a control component 8, directs the refrigerant fluid circulating in the second branch 22 to a point as far as the first confluence point 45 and the reservoir 4 or the bypass branch 25. According to this configuration for cooling the vehicle's passenger compartment, the three-way valve 82 redirects all the refrigerant fluid that has passed through the third heat exchanger 33 back to the bypass branch 25. Therefore, the inlet to the first confluence point 45 is completely closed.

[0075] The refrigerant fluid bypasses the fourth heat exchanger 34 and the receiver 4 by circulating within the bypass branch 25. However, the refrigerant fluid circulates through the fifth heat exchanger 35, which has the effect of increasing the temperature of the refrigerant fluid in the bypass branch 25 to ensure that no condensation occurs during the circulation of the refrigerant fluid within the bypass branch 25. The refrigerant fluid then reaches the main branch 20 and the compressor 3 via the second confluence point 46.

[0076] In this mode used for cooling the vehicle passenger compartment, the first valve 51 and the second valve 52 are in the closed position, so that the refrigerant fluid does not circulate in the third branch 23 and the fourth branch 24.

[0077] Figure 4 A second embodiment of the refrigerant fluid circuit 2 is shown, and more particularly, the circulation of the refrigerant fluid according to a pattern for heating the passenger compartment of a vehicle is shown. The purpose of this pattern is to heat the passenger compartment of the vehicle while cooling the electrical storage equipment.

[0078] The circulation of the refrigerant fluid is then restarted by the compressor 3. The high-temperature refrigerant fluid then exchanges its heat energy with the heat transfer liquid in the sixth heat exchanger 36. The heat transfer liquid participates in the heating of the vehicle's passenger compartment, for example, by exchanging heat with the internal airflow 6, while being heated through the heat exchange performed by the sixth heat exchanger 36.

[0079] After passing through the sixth heat exchanger 36, the refrigerant fluid reaches the third branch point 43. With the first valve 51 open, the refrigerant fluid can circulate within the third branch 23. The refrigerant fluid thus separates into two parts. The first part continues to circulate within the main branch 20 and expands via the expansion member 37 before passing through the first heat exchanger 31. This expansion of the refrigerant fluid makes it possible to cool the external airflow 5, allowing the external airflow to recover heat energy, for example, by passing through a third heat exchanger located downstream of the first heat exchanger 31 in the circulation direction relative to the external airflow 5.

[0080] With the second valve 52 open, the first portion of the refrigerant fluid reaches the fourth branch point 44 after passing through the first heat exchanger 31 and circulates within the fourth branch 24. This fourth branch 24 allows the refrigerant fluid at the output of the first heat exchanger 31 to directly reach the first convergence point 45 and the receiver 4, without passing through the first branch 21 or the second branch 22. Therefore, the objective here is to heat the heat transfer liquid via the sixth heat exchanger 36 and, if possible, cool the external airflow 5.

[0081] At the output of the reservoir 4, the refrigerant fluid circulates to the compressor 3 in the same manner as the refrigerant fluid used for cooling the passenger compartment of the vehicle (that is, by circulating in the main branch 20 and more specifically by passing through the second section 62 of the fourth heat exchanger 34; if the refrigerant fluid did not circulate in the first branch 21, the passage would not function).

[0082] Regarding the second portion of the refrigerant fluid, it circulates within the third branch 23 to bypass the first heat exchanger 31 and reach the third confluence point 47. Once the second portion of the refrigerant fluid has reached the third confluence point 47, the check valve 53 prevents it from circulating back to the first heat exchanger 31. The refrigerant fluid then circulates only in the second branch 22, while the first branch 21 is involved in cooling the vehicle's passenger compartment.

[0083] As with the mode used to cool the passenger compartment of a vehicle, the refrigerant fluid circulates in the second branch 22, is pre-cooled by the fifth heat exchanger 35, and then expands through the expansion device 39 before passing through the third heat exchanger 33 in order to recover heat energy from the heat transfer liquid.

[0084] Subsequently, the second portion of the refrigerant fluid reaches the second branch point 42. Depending on the mode used for heating the passenger compartment, the heat recovery occurring at the third heat exchanger 33 may be insufficient to effectively evaporate all the refrigerant fluid. To overcome this, the three-way valve 82 is parameterized to allow a portion of the second portion of the refrigerant fluid to circulate as far as the end of the second branch 22, and thus as far as the receiver 4, in order to maintain the refrigerant fluid in liquid form. The three-way valve 82 may, for example, be parameterized to circulate 10% to 20% of the second portion of the refrigerant fluid to the receiver 4.

[0085] The remainder of the second section circulates within the bypass branch 25. The circulation within the bypass branch 25 is affected until it reaches the main branch 20 upstream of the compressor 3 in the same manner as the refrigerant fluid circulates in the bypass branch 25 according to the pattern used for cooling the passenger compartment of the vehicle (that is, especially by circulating in the second section 64 of the fifth heat exchanger 35, which has the effect of increasing the temperature of the refrigerant fluid circulating in the bypass branch).

[0086] Figure 5 A second embodiment of the refrigerant fluid circuit 2, including an alternative control component 8 such as the three-way valve shown in the previous figure, is illustrated. Figure 5 In this configuration, the control element 8 takes the form of a variable-opening valve 81, which is not located at the second branch point 42 as described above, but rather on the second branch 22, downstream of the second branch point 42 and upstream of the first convergence point 45. The variable-opening valve 81 can be remotely controlled, for example, to determine the degree of opening that allows for the desired distribution of refrigerant fluid. The higher the degree of opening of the variable-opening valve 81, the more refrigerant fluid circulates from the output of the third heat exchanger 33 to the receiver 4. Conversely, the lower the degree of opening of the variable-opening valve 81, the less refrigerant fluid circulates from the output of the third heat exchanger 33 to the receiver 4, and therefore the more refrigerant fluid circulates within the bypass branch 25 at the output of the third heat exchanger 33.

[0087] exist Figure 5 In this configuration, the variable opening valve 81 is located on the second branch 22, but it can also be positioned on the bypass branch 25, between the second branch point 42 and the second section 64 of the fifth heat exchanger 35. In this configuration, the lower the opening degree of the variable opening valve 81, the less refrigerant fluid circulates in the bypass branch 25 at the output of the third heat exchanger 33, and therefore the more refrigerant fluid circulates to the receiver 4 at the output of the third heat exchanger 33.

[0088] Therefore, the control component 8 can have a different nature, the key point being that it can be remotely controlled in order to perform any distribution of the refrigerant fluid leaving the third heat exchanger 33.

[0089] The sixth heat exchanger 36 is also with Figures 2 to 4 The difference lies in that it is configured to perform heat exchange directly with the internal airflow 6, rather than indirectly with the heat exchange fluid as described above. Thus, the internal airflow 6 acts as the heat transfer fluid 10. According to this alternative, the sixth heat exchanger 36 can then be arranged within the aforementioned ventilation, heating, and / or air conditioning system, like the second heat exchanger 32.

[0090] Of course, the present invention is not limited to the examples just described, and many modifications can be made to these examples without departing from the scope of the present invention.

[0091] As just described above, the present invention does indeed achieve its stated objectives and enables the provision of a simplified refrigerant fluid circuit that still allows for the avoidance of any pressure drop by means of a bypass branch that bypasses the receiver. Variations not described herein may be implemented without departing from the context of the invention, provided that such variations include the refrigerant fluid circuit according to the invention.

Claims

1. A refrigerant fluid circuit (2) for a heat treatment system, the refrigerant fluid circuit comprising a main branch (20) starting at a first confluence point (45) and ending at a first branch point (41) and including at least one reservoir (4), a compression device (3), and at least a first heat exchanger (31), the refrigerant fluid circuit (2) including at least a first branch (21) and a second branch (22), both the first branch and the second branch starting at the first branch point (41) and ending at the first confluence point (45), the first branch (21) including at least a second heat exchanger (32) and an expansion element (38) located upstream of the second heat exchanger (32), the second branch including at least a third heat exchanger (33) and further including an expansion device (39) arranged upstream of the third heat exchanger (33), characterized in that, The refrigerant fluid circuit (2) includes a bypass branch (25) that originates at a second branch point (42) on the second branch (22) downstream of the third heat exchanger (33) and terminates at a second convergence point (46) on the main branch (20) downstream of the reservoir (4) and upstream of the compressor (3). The refrigerant fluid circuit includes a control member (8) configured to manage the circulation of refrigerant fluid from the second branch (22) to the reservoir (4) and / or to the bypass branch (25).

2. The refrigerant fluid circuit (2) of claim 1, wherein, The control component (8) is located on the second branch (22) downstream of the third heat exchanger (33).

3. The refrigerant fluid circuit (2) of claim 1, wherein, The first heat exchanger (31) is configured to perform heat exchange between the refrigerant fluid circulating in the main branch (20) and the external airflow (5) to the passenger compartment of the vehicle.

4. The refrigerant fluid circuit (2) of claim 1, wherein, The second heat exchanger (32) is configured to perform heat exchange between the refrigerant fluid circulating in the first branch (21) and the internal airflow (6) intended to be delivered into the passenger compartment of the vehicle.

5. The refrigerant fluid circuit (2) of claim 1, wherein, The third heat exchanger (33) is configured to perform heat exchange between the refrigerant fluid circulating in the second branch (22) and the heat transfer liquid circuit (7).

6. The refrigerant fluid circuit of claim 1, wherein the refrigerant fluid circuit includes an expansion member (37) disposed upstream of the first heat exchanger (31).

7. The refrigerant fluid circuit (2) of claim 1, wherein the refrigerant fluid circuit includes a fourth heat exchanger (34), the fourth heat exchanger including a first section (61) disposed on the first branch (21) upstream of the expansion element (38) and a second section (62) disposed on the main branch (20) downstream of the reservoir (4) and upstream of the second confluence point (46), the fourth heat exchanger (34) being configured to perform heat exchange between the refrigerant fluid circulating in the first branch (21) and the refrigerant fluid circulating in the main branch (20), the bypass branch (25) being configured to allow the refrigerant fluid to circulate such that the refrigerant fluid bypasses the fourth heat exchanger (34) and the reservoir (4).

8. The refrigerant fluid circuit (2) of claim 1, wherein, The control component (8) is a variable opening valve (81), which is located on the second branch (22), downstream of the second branch point (42) and upstream of the first converging point (45), or on the bypass branch (25), downstream of the second branch point (42) and upstream of the second converging point (46).

9. The refrigerant fluid circuit (2) of claim 1, wherein, The control component (8) is a three-way valve (82) installed at the second branch point (42).

10. A method for controlling a refrigerant fluid circuit (2) as claimed in any one of claims 1 to 9, wherein during the method: - In the mode for cooling the passenger compartment of the vehicle, the control element (8) is adjusted such that all refrigerant fluid circulates in the bypass branch (25). - In the mode for heating the passenger compartment of the vehicle, the control component (8) is adjusted to determine the proportion of refrigerant fluid circulating to the reservoir (4) and / or in the bypass branch (25).

11. The control method of claim 10, wherein during the method, in a mode for heating the passenger compartment of the vehicle, the refrigerant fluid recovers heat energy by passing through a third heat exchanger (33).

Images