Scroll compressor for a thermal management system

Abstract

A scroll compressor (1) for a thermal management system (2), in particular for a motor vehicle, comprising two spiral elements (6, 7) which are arranged so as to be nested in one another at least in sections and which are movable relative to one another, the scroll compressor (1) being designed to receive fluid in an inlet section (8) between the spiral elements (6, 7) and to compress said fluid in at least one intermediate space section (9) between the spiral elements (6, 7) by means of the relative movement of the spiral elements (6, 7), the scroll compressor (1) being designed to set a mass flow of the fluid compressed by the scroll compressor (1) independently of the rotational speed.

Description

[0001] ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0002] Scroll compressor for a thermal management system

[0003] The invention relates to a scroll compressor for a thermal management system, in particular for a motor vehicle, comprising two spiral elements arranged at least partially nested within each other, which are movable relative to each other, wherein the scroll compressor is designed to receive fluid in an inlet section between the spiral elements and to compress it in at least one intermediate space section between the spiral elements by means of the relative movement of the spiral elements.

[0004] Scroll compressors for thermal management systems, i.e., compression devices or compressors also known as "scroll" or "scroll-type" compressors, are generally used for compressing refrigerants in thermal management systems. Typically, such a scroll compressor has a defined suction volume, resulting in a specific output that is limited by the compressor's design. For example, the output of the scroll compressor, or the achieved mass flow rate, is controlled by the rotational speed of the electric motor that drives the compression unit or the scroll elements of the scroll compressor.Since the scroll compressor is usually designed for the maximum expected power requirement, low power requirements during operation may no longer be able to be controlled solely via the speed, so that intermittent operation of the scroll compressor must be carried out.

[0005] If the required output falls below the minimum possible mass flow rate, a power surplus occurs and the power balance cannot be maintained. Therefore, in this case, the scroll compressor is operated in the described intermittent mode, in which it is switched off and later restarted to regulate the average output of the thermal management system within the required range. The disadvantages of this intermittent operation include high mechanical wear and, in particular, significantly lower efficiency compared to constant operation, as the refrigeration cycle must be readjusted after each start. ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0006] The larger the suction volume of the scroll compressor, the more critical the capacity control becomes at low performance demands. The design or selection of the suction volume therefore always represents a compromise that balances performance requirements with efficiency. Consequently, limitations in the extreme performance ranges must be accepted.

[0007] The invention is based on the objective of providing an improved scroll compressor for a thermal management system, in which operation at low power requirements is improved in particular.

[0008] The problem is solved by a scroll compressor with the features of claim 1. Advantageous embodiments are the subject of the dependent claims.

[0009] As described, the invention relates to a scroll compressor for a thermal management system, specifically for a motor vehicle. The scroll compressor comprises two spiral elements arranged at least partially nested within one another, which are movable relative to each other. The scroll compressor is designed to receive fluid in an inlet section between the spiral elements and to compress it in at least one intermediate space between the spiral elements by means of the relative movement of the spiral elements.

[0010] In other words, the scroll compressor is used to compress fluid, specifically gaseous refrigerant, in the refrigerant circuit of the thermal management system. The scroll compressor draws in gaseous refrigerant, compresses it, and delivers the pressurized refrigerant to at least one other component in the refrigerant circuit, such as a condenser. In the condenser, thermal energy is extracted from the refrigerant. This cools the refrigerant until it falls below its boiling point, causing it to undergo a phase change and become at least partially liquid. The liquid refrigerant can then be expanded by an expansion valve, such as a throttle valve.This low-pressure refrigerant can be fed to an evaporator, where energy can be added back to the refrigerant (ZF Friedrichshafen AG File 305260, Friedrichshafen, 2024-09-26), causing it to return to a gaseous state. The scroll compressor draws in the low-pressure refrigerant through the compressor drive, for example, an electric motor, absorbing its waste heat in the process. The process then begins again.

[0011] In principle, compressors in motor vehicles can be driven either mechanically by the combustion engine or, increasingly, by their own electric drive motor. The thermal output correlates directly with the mass flow rate. The scroll compressor has a geometrically defined suction volume and is formed from two spiral elements, i.e., helical components, whose spirals interlock. The first spiral element can be fixed to the housing, while the second can perform an orbital motion relative to the first spiral element due to the drive mechanism. During this orbital motion, two radially opposing, expanding spaces are opened between the two spiral elements, allowing fluid, i.e., refrigerant, to flow in.As the second spiral element moves further, the distance between the walls of the two spiral elements decreases, thereby trapping the fluid. The volume trapped in the two cavities or interstitial spaces corresponds to the geometric suction volume.

[0012] The invention is based on the understanding that the scroll compressor is designed to adjust the mass flow rate of the fluid compressed by the scroll compressor independently of the rotational speed. In other words, it is proposed here that the scroll compressor does not compress the entire intake volume in every operating condition, but rather selectively compresses only a portion of the intake volume in order to influence the mass flow rate. This creates a deviation between the geometric intake volume and the actual compressed volume of the fluid. This can be achieved largely or completely independently of the rotational speed of the scroll compressor's drive, for example, the electric motor that drives the scroll compressor. This means that a mass flow rate adapted to the required performance can be set at any operating speed of the scroll compressor.Therefore, it is advantageous that there is no ZF Friedrichshafen AG file 305260 Friedrichshafen 2024-09-26.

[0013] Off-peak operation or intermittent operation of the scroll compressor is not required to cover operation with low power demands. Instead, the proportion of the total intake volume of refrigerant that is compressed can be adjusted, thus influencing the mass flow rate.

[0014] Particularly in operating conditions that cannot be covered by simple speed control when compressing the entire intake volume, and thus intermittent operation would be necessary, the proportion of the compressed volume to the total intake volume can instead be reduced, thereby lowering the mass flow rate of the fluid compressed by the scroll compressor. Consequently, the scroll compressor can be operated continuously, and the mass flow rate can be adjusted not only by the speed of the scroll compressor's drive unit but also by controlling how much of the intake volume of refrigerant is actually compressed and fed into the refrigerant circuit of the next component, for example, the condenser.Although the scroll compressor is thus designed to adjust the mass flow independently of the speed, it is still possible to control the scroll compressor by adjusting the mass flow in combination with the speed and the setting of the proportion of the intake volume compressed by the scroll compressor.

[0015] In a further development of the scroll compressor, it can be provided that at least one drain opening is arranged in the intermediate space section and that the scroll compressor is designed to drain or expel at least a portion of the fluid from the drain opening, particularly during relative movement of the spiral elements. This means that a specific volume, determined by the dimensions of the scroll compressor or the spiral elements and the inlet section or the intermediate space section between the spiral elements, essentially defines the volume drawn into the intermediate space section through the inlet section, for example, the geometric suction volume described above.However, at least one drain opening in the intermediate space allows a portion of this refrigerant volume to be expelled, meaning that this portion is not compressed. Only the remaining portion of the volume, which is not expelled through the drain opening but remains in the intermediate space, is actually compressed. The effective portion of the intermediate space can therefore be determined by selectively expelling fluid through the drain opening.

[0016] The scroll compressor described herein can, as described, be considered a compressor, particularly for a heat pump. The scroll compressor is electrically driven and features a scroll-type compressor unit. For driving the compressor unit, the scroll compressor has an electric machine or an electric drive motor. In addition to the high-pressure outlet, the stationary scroll or spiral element has at least one discharge opening, for example, a discharge bore, located within the geometric suction volume or in the space between the spiral elements.

[0017] This drain port advantageously has a closing mechanism, allowing some of the trapped suction volume to escape during compression, thus reducing the amount of fluid pumped during subsequent compression. This means the drain port can be closed at a specific operating state, after fluid has been drained or expelled through the port. By adjusting the operating state or the point in time during compression at which the drain port is closed, the proportion of the refrigerant volume being compressed relative to the total suction volume can be controlled.

[0018] If at least one drain opening is positioned near the intake area, fluid can flow out until the spiral wall of the spiral element passes over the drain opening, allowing the refrigerant remaining in the intermediate space to be compressed. Depending on the position, this can reduce the mass flow rate, for example by up to 15%. If at least one drain opening is positioned further within the intake volume or the intermediate space, up to 70% of the intake volume of refrigerant can flow out again. (Depending on the requirements of ZF Friedrichshafen AG, File 305260, Friedrichshafen, 2024-09-26)

[0019] The scroll compressor or the thermal management system can thus be flexibly adjusted to a large extent to ensure a minimum required output before shutdown is necessary, so that shutdown or intermittent operation can be avoided or reduced.

[0020] In one embodiment of the scroll compressor, the at least one outlet opening can be designed to reduce the maximum volume of fluid taken in through the inlet section to an actual volume that is compressed within the scroll compressor. As previously described, the outlet opening is designed to enable under-load operation. During under-load operation, fluid that has already flowed into the intermediate space section, namely through the inlet section, is expelled through the outlet opening. Due to the relative movement of the spiral elements, the volume of the intermediate space section is continuously reduced, as the enclosed fluid volume is guided spirally towards the center of the spiral elements. However, as long as the at least one outlet opening is open, fluid can flow out of the intermediate space section.Therefore, the actual volume that is actually compressed in the scroll compressor is reduced compared to the maximum volume.

[0021] In other words, the maximum volume can be utilized if the drain opening is always closed. Depending on the location of the drain opening and when it closes during the movement of the spiral elements, the actual volume can be reduced compared to the maximum volume.

[0022] The scroll compressor can further be configured to discharge uncompressed fluid, particularly in an inlet area, or at least partially compressed fluid, particularly in a compression area, through at least one discharge opening. As described above, fluid is drawn in through the inlet section between the two spiral elements in the interspace section and subsequently compressed as soon as the spiral elements have moved relative to each other due to their orbital motion, i.e., their circular relative motion, and the inlet section is closed. ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0023] In principle, it is therefore possible to arrange at least one drain opening in the inlet area, i.e., near the inlet section, so that uncompressed fluid can flow directly out of the intermediate space section through the open drain opening. Likewise, it is possible to arrange at least one drain opening in a compression section, so that when this drain opening is open, already compressed fluid can be released from the intermediate space section, namely in the compression section where the fluid is already compressed.

[0024] In principle, the fluid discharged from the drain opening can be returned to the refrigerant circuit as desired. Advantageously, the fluid flowing from the at least one drain opening is returned directly to the low-pressure section of the refrigerant circuit, for example, directly to the inlet section. Depending on where the refrigerant is drawn from the intermediate space section, for example, in the compression section, it can also be supplied to another section of the refrigerant circuit, such as a medium-pressure or high-pressure section. The refrigerant circuit or the scroll compressor therefore preferably has lines or other suitable features (e.g., component design) that enable or create such connections.

[0025] The scroll compressor may further be provided with at least one spiral element, in particular the movable spiral element, configured to release the at least one discharge opening in a discharge state and / or to close the at least one discharge opening in a compression state, and / or it may be provided that the scroll compressor has at least one valve device configured to release the at least one discharge opening in a discharge state and / or to close the at least one discharge opening in a compression state. In the first described embodiment, the movable spiral element can cover the discharge opening during the relative movement between the spiral elements, thus closing it or disconnecting the space between the two spiral elements from the discharge opening.This results in the drain opening being closed by the movement of the spiral elements themselves at a certain point of movement or from reaching a certain relative position of the two spiral elements to each other during the relative movement ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26.

[0026] Alternatively, at least one valve assembly can be provided that can open or close at least one drain opening depending on the valve assembly's closing state. The valve assembly can, for example, be designed as a solenoid valve and can thus change its closing state, for example, by electrical control. Alternatively, the valve assembly can also be pressure-controlled. The use of the valve assembly can, in particular, make it possible to precisely adjust the amount of fluid that is discharged or the actual volume of fluid in the intermediate space that is to be compressed by the further relative movement of the spiral elements.

[0027] The closure of at least one drain opening, or the shutdown of the outflow, is advantageously achieved in a design using an actively controlled outflow valve. This design allows for particular consideration of the volume in the outflow line, since fluid is expelled into this outflow line when the outflow is shut off, until the bore is passed over by the spiral element. This fluid then expands back into the subsequent suction volume. This leads to losses that should be avoided as much as possible. To this end, the valve should be positioned as close as possible to the outflow bore, or the line cross-section should be designed to be correspondingly small, so that the effect becomes negligible.

[0028] As described, the valve assembly can generally be electrically controlled or controlled by pressure, in particular the fluid pressure of the fluid compressed by the scroll compressor, specifically the refrigerant. In one embodiment, the valve assembly may have at least one valve element connected to a high-pressure circuit and at least one check valve connected to the drain opening. This makes it possible to apply pressure to the check valve via the valve element, which must be overcome by the fluid pressure in the intermediate space connected to the drain opening.This means that the check valve remains closed and therefore the drain opening ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26 is sealed until the pressure in the intermediate space section exceeds the pressure applied to the check valve from the high-pressure circuit by means of the valve element.

[0029] Alternatively, pressurized fluid from the high-pressure circuit can be supplied through the valve element in such a way that the check valve opens and the at least one drain port is released. In the described embodiment, the at least one drain port can be closed, for example, by means of a plate valve. Using the described valve element, for example, an active pressure inlet valve, fluid is directed from the high-pressure circuit into the discharge line so that the discharge port can be selectively released. The pressure inlet valve is advantageously designed as a 3-2-way valve, which, when activated, opens a channel towards the low-pressure side, thus enabling overflow.

[0030] Furthermore, the scroll compressor may be provided with a bypass line that connects at least one drain port to a low-pressure circuit, in particular to the inlet section. As already described, it is generally possible for the drain port to be connected to any section of the refrigerant circuit via a corresponding discharge line or the bypass line described herein. The bypass line described herein connects the drain port, for example, directly to a low-pressure circuit, specifically to the inlet section. This means that fluid drained from the drain port can be returned directly to the inlet section to be drawn back in.

[0031] In a further development of the scroll compressor, a channel intended for other purposes, such as a medium-pressure channel of a vapor-injection version ("VI version") of the scroll compressor, can be used to control the overflow. To implement the Vl function, a so-called Vl channel is provided, which terminates in the stationary spiral element and connects radially further inwards on the scroll compressor to the intermediate chamber sections in the axial direction. The pressure level here is higher than the low pressure, but below the high pressure level. ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0032] If this pressure is higher than the pressure in the compression chamber, i.e., the intermediate space section, additional fluid is supplied to the already at least partially compressed fluid until either the pressure level is equalized or the spiral wall of the spiral element opens the next chamber. This intermediate pressure in the line is advantageously used as the control pressure for the drain valves or check valves, as described above. The position of the drain openings, or at least one drain opening, is preferably chosen such that the compression pressure is close to the intermediate pressure level.

[0033] This intermediate pressure level can be advantageously used to control the drain valves by directing this intermediate pressure to the valves via a branch line. When intermediate pressure is present, the drain valves are closed, and the mass flow rate corresponds to the mass flow rate resulting from the suction volume, i.e., the mass flow rate resulting from the maximum volume. When the intermediate pressure channel is depressurized, the fluid can flow out of the suction volume. It seems particularly useful if a fluidic connection to the low-pressure area can be opened simultaneously with the depressurization of the intermediate pressure.

[0034] A variation of this can be implemented such that the intermediate pressure channel is fluidically connected to the low-pressure area via an orifice or throttle. As long as intermediate pressure is present, fluid is expanded through this channel into the low-pressure area, but the majority of this fluid can be used for the Vl function. When intermediate pressure is switched off, the fluid flowing from the compression chamber can be directed through the orifice into the low-pressure area.

[0035] In a further development, the medium-pressure supply line is used as an exhaust line, so that in the event of underload control, the medium-pressure injection is switched off and volume is drained from the compressor. This function can be ensured by appropriately positioning at least one drain port; however, the port is always located within the area of ​​the pre-compressed fluid, which is likely to result in additional losses. ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0036] As described at the outset, the scroll compressor can have at least one outlet opening. In one embodiment, the scroll compressor can have at least two outlet openings arranged opposite each other with respect to a center point and / or a central axis of the spiral elements. The spiral elements can, for example, define two inlet sections into which fluid can be drawn in or flowed, opposite each other with respect to the center point and / or the central axis. Each inlet section and the adjoining intermediate sections can each have at least one outlet opening.

[0037] In addition to the described scroll compressor, the invention relates to a thermal management system comprising such a scroll compressor. Furthermore, the invention relates to a motor vehicle comprising a previously described scroll compressor and / or such a thermal management system. The invention also relates to a method for operating a scroll compressor for a thermal management system, particularly for a motor vehicle, comprising two spiral elements arranged at least partially nested within one another, which are relatively movable, wherein fluid is drawn into an inlet section between the spiral elements and compressed in at least one intermediate space section between the spiral elements by means of the relative movement of the spiral elements, wherein a mass flow rate of the fluid compressed by the scroll compressor is adjusted independently of the rotational speed.

[0038] All the advantages, details, and features described in relation to the scroll compressor are fully transferable to the thermal management system, the motor vehicle, and the process, and vice versa. In particular, a previously described scroll compressor is used to operate the process.

[0039] In this description, temperature control refers to cooling or heating.

[0040] A thermal management system is a system that regulates the temperature of at least two consumers. A consumer is therefore a device that needs to be cooled or heated. One consumer can be for cooling and the other for heating (ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26). These consumers can even be located in the same cooling circuit, as will be shown below.

[0041] Preferably, a consumer can be an electric machine. Furthermore, a consumer can be an inverter. Additionally or alternatively, a consumer can be a passenger compartment. Advantageously, a consumer can be a battery.

[0042] The thermal management system comprises at least one coolant circuit. Preferably, the thermal management system comprises at least one refrigerant circuit and one coolant circuit. At least one cooling device may be arranged in the refrigerant circuit. This cooling device cools the refrigerant. The cooling circuit is cooled via the refrigerant and is in direct connection with at least one consumer.

[0043] Furthermore, the thermal management system can have at least two, and in particular exactly two, coolant circuits and one refrigerant circuit. The cooling circuits are cooled via the refrigerant and are in direct contact with the consumers.

[0044] Preferably, one of the refrigerant circuits can be configured as a high-temperature circuit and the other as a low-temperature circuit. The high-temperature circuit is thermally connected to the refrigerant circuit at a first point, and the low-temperature circuit at a second point. The first point has a higher temperature than the second point. In particular, the high-temperature circuit can be connected downstream of a compressor. Preferably, the low-temperature circuit can be connected downstream of an evaporator.

[0045] The temperature to which the high-temperature circuit is cooled can be, for example, 40°C. This temperature can be used simultaneously to heat one component, such as the passenger compartment, and to cool another component, such as an electric motor. ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0046] The low-temperature circuit is cooled to a lower temperature than the high-temperature circuit. This allows the cooling capacity to be concentrated on the low-temperature circuit, to which the largest cooling load, such as power electronics, is connected. This optimizes the provision of cooling capacity and allows, for example, the compressor to be smaller.

[0047] A radiator can preferably be arranged in the low-temperature circuit.

[0048] Advantageously, a passenger compartment and / or an electric motor and / or a battery can be arranged as consumers in the high-temperature circuit. Furthermore, a power electronics assembly, in particular an inverter, can be arranged in the low-temperature circuit.

[0049] The cooling device can be designed as a heat pump. The heat pump comprises at least two heat exchangers and a compressor. One of the heat exchangers can be designed as a condenser and the other as an evaporator.

[0050] Preferably, the refrigerant in the refrigerant circuit is a natural refrigerant, in particular propane. Alternatively, the coolant in the cooling circuit(s) can be a water-glycol mixture.

[0051] Preferably, the thermal management system includes a distribution unit. The distribution unit controls which circuit is connected to which other circuit and which consumer. The distribution unit is also referred to as a Fluid Control Unit (FCU). Advantageously, the distribution unit includes a valve unit with at least one valve. The valve can be a spool valve, in particular an axial spool valve or a rotary spool valve. In particular, the valve unit can include at least four, preferably exactly four, valves.

[0052] The distribution unit can have at least two housing parts. Channel structures and / or ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0053] Valve receiving areas may be provided. Alternatively, one housing part may be designed as a cover without any structures, and only one housing part may have channel structures and / or valve receiving areas. It is also conceivable to provide only valve receiving areas in one housing part and only channel structures in the other housing part.

[0054] Furthermore, the thermal management system comprises a pump arrangement with at least one pump. Preferably, the pump arrangement can comprise at least two, and in particular exactly two, pumps. At least one pump can be a rotor pump. At least one pump can be a vane pump.

[0055] Alternatively, the thermal management system can also be installed in a stationary position, e.g. in a building.

[0056] The invention is explained below with reference to exemplary embodiments and the figures. The figures are schematic representations and show:

[0057] Fig. 1 shows a schematic representation of a section of a scroll compressor according to a first embodiment in a first operating state;

[0058] Fig. 2 of the scroll compressor from Fig. 1 in a second operating state;

[0059] Fig. 3 shows a schematic representation of a section of a scroll compressor according to a second embodiment;

[0060] Fig. 4 shows a schematic representation of a section of a scroll compressor according to a third embodiment;

[0061] Fig. 5 shows a schematic representation of a section of a scroll compressor according to a fourth embodiment; ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0062] Fig. 6 shows a schematic representation of a section of a scroll compressor according to a fifth embodiment in a first operating state;

[0063] Fig. 7 of the scroll compressor from Fig. 6 in a second operating state;

[0064] Fig. 8 of the scroll compressor from Fig. 6, 7 in a third operating state;

[0065] Fig. 9 of the scroll compressor from Fig. 6-8 in a fourth operating state;

[0066] Fig. 10 shows a schematic representation of a thermal management system with a scroll compressor according to a sixth embodiment;

[0067] Fig. 11 shows a schematic representation of a thermal management system with a scroll compressor according to a seventh embodiment;

[0068] Fig. 12 shows a schematic representation of a thermal management system with a scroll compressor according to an eighth embodiment;

[0069] Fig. 13 shows a schematic representation of a thermal management system with a scroll compressor according to a ninth embodiment;

[0070] Fig. 14 shows a schematic representation of a thermal management system with a scroll compressor according to a tenth embodiment;

[0071] Fig. 15 shows a schematic representation of a thermal management system with a scroll compressor according to an eleventh embodiment.

[0072] Fig. 1 shows an example of a scroll compressor 1 for a thermal management system 2, specifically for a motor vehicle. As described below with reference to Figs. 10-15, the scroll compressor can be part of the thermal management system 2 to compress fluid, specifically refrigerant, and supply the refrigerant to a component of the thermal management system 2, for example, a condenser s. The refrigerant or fluid is then expanded by an expansion valve 4 and supplied to an evaporator 5. From there, the refrigerant returns to the scroll compressor 1. Via the condenser 3 and the evaporator 5, the refrigerant circuit of the thermal management system 2 is coupled to coolant circuits, for example, a high-temperature circuit on the condenser 3 side and a low-temperature circuit on the evaporator 5 side.

[0073] Fig. 1 shows a section of the scroll compressor 1 in the axial direction relative to the axis of movement, i.e., perpendicular to the plane in which the movement of the two spiral elements 6, 7 of the scroll compressor 1 takes place. By way of example, one of the spiral elements 6, 7 can be movable and the other fixed. The scroll compressor 1 has an inlet section 8 through which fluid can be drawn in or through which fluid can flow into an intermediate space 9 between the two spiral elements 6, 7. Following the basic operating principle of a scroll compressor, due to the relative movement, a volume of fluid enclosed in the intermediate space 9, as shown, for example, in Fig. 2, is moved radially inward in a spiral motion by the further relative movement of the spiral elements 6, 7 and thus compressed due to the ever-decreasing intermediate space 9.

[0074] The scroll compressor 1 described herein is fundamentally designed to adjust the mass flow rate of the fluid compressed by the scroll compressor 1 independently of its rotational speed. This means that, on the one hand, the mass flow rate can be changed by changing the rotational speed of the scroll compressor 1 or the drive unit associated with the scroll compressor 1, for example, an electric machine or an electric motor, but this can also be done independently of the rotational speed of the drive unit.

[0075] For this purpose, the scroll compressor 1 has at least one drain opening 10, 11, for example, two drain openings 10, 11. Through the at least one drain opening 10, 11, it is possible for fluid to leave the intermediate space section 9 again. In other words, during the relative movement of the spiral elements 6, 7 shown in Figs. 1, 2, the intermediate space section 9 is reduced in size. However, this does not necessarily result in compression of the fluid, but rather allows some of the fluid to escape from the intermediate space section 9 through the at least one drain opening 10, 11. This changes the effective volume of the intermediate space section 9, regardless of the rotational speed at which the spiral elements 6, 7 are moved relative to each other.

[0076] To adjust the proportion of fluid volume that is discharged and not compressed, or the proportion of fluid that is compressed relative to the total intake volume or maximum volume, several options are possible, which are described below. In other words, the maximum volume is utilized, and thus the maximum mass flow rate is compressed in the scroll compressor 1, when the discharge openings 10, 11 remain closed. Depending on the proportion of the relative movement of the spiral elements 6, 7 during which the discharge openings 10, 11 remain open, and how long they remain open, the volume or mass of the fluid is reduced by the discharge of fluid through the discharge openings 10, 11, thereby also reducing the mass flow rate. Advantageously, this makes it possible to operate at reduced loads without affecting the rotational speed.Specifically, it is therefore not necessary to operate the scroll compressor 1 intermittently or to switch off the scroll compressor 1 in order to cover a minimum performance requirement.

[0077] Fig. 3 shows, by way of example, that the drain openings 10, 11 are connected to a common channel or outflow line 12. Also shown is a valve assembly 13, which may include a valve element 14. The valve assembly 13 is generally designed to close or open the drain openings 10, 11. In a compression state, the valve assembly 13 closes the drain openings 10, 11 or the outflow line 12, so that the volume of fluid in the intermediate space section 9 cannot escape and is therefore compressed. In a drain state, the valve assembly 13 can open the valve element 14, so that the fluid can escape from the intermediate space section 9 and, for example, be fed back to the inlet section 8 via the outflow line 12. The valve element 14 can close the drain openings 10, 11 at any desired time.upon reaching a certain operating point of ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26.

[0078] Relative motion opens and closes, allowing any proportion of the fluid to be expelled.

[0079] Fig. 4 shows an alternative embodiment in which the valve device 13 can be connected to a medium pressure level or a high pressure level, by which a pressure level can be applied in the outflow line 12 that prevents fluid from flowing out of the intermediate space section 9 as long as the pressure in the intermediate space section 9 does not reach the pressure level in the outflow line 12.

[0080] For example, a pressure can be specifically set in the discharge line 12 up to which the drain openings 10, 11 remain closed. If the pressure level is reached or exceeded by further compressing the fluid in the intermediate space section 9 due to the relative movement of the spiral elements 6, 7, a discharge can occur, for example, for an operating condition in which the maximum pressure is not required. If, for example, the maximum pressure is applied to the discharge line 12, the drain openings 10, 11 do not open, so that the scroll compressor 1 can be operated with maximum mass flow or with the maximum volume of the intermediate space section 9 as the effective volume.

[0081] Fig. 5 shows a further embodiment in which check valves 15 are provided in the drain openings 10, 11. The check valves 15 generally open when the pressure in the intermediate space section 9 exceeds the preload of the check valves 15. The valve assembly 13 also makes it possible to apply additional pressure in the discharge line 12, which further closes the check valves 15. Consequently, the check valves 15 are only opened when the fluid pressure in the intermediate space section 9 is sufficient to open the additionally preloaded check valves 15.

[0082] In principle, it is also possible to arrange the check valves 15 in reverse, so that the pressure fed into the drain line 12 can open them against the spring preload (ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26). This makes it possible, for example, to open the drain openings 10, 11 in a pressure-controlled manner.

[0083] Figures 6-9 further illustrate that, alternatively or additionally to using an active valve device 13, which may, for example, comprise a pressure-controlled or electrically controlled valve element 14, it is also possible to block the at least one drain opening 10, 11 by the spiral elements 6, 7. As shown, for example, the spiral element 6 can be stationary and the spiral element 7 movable relative to the stationary spiral element 6, with the drain openings being provided in the stationary spiral element 6. Figure 6 shows that fluid can be drawn into the intermediate space section 9 through the inlet section 8. In this state, the drain openings 10, 11 are released.

[0084] Figure 7 shows that the spiral element 7 has moved relative to the spiral element 6, thereby closing the inlet section 8 and enclosing the volume in the intermediate section 9. In this case, the spiral element 7 can cover the outlet openings 10, 11. In the next compression stroke, as shown in Figure 8, further relative movement of the spiral element 7 relative to the spiral element 6 releases the outlet opening 10, 11, allowing fluid to be expelled from the intermediate section 9 through the outlet opening 10. However, the fluid is only expelled through the outlet opening 10 until the spiral element 7 closes the outlet opening 10 again, as shown, for example, in Figure 9. The remaining volume of fluid in the intermediate section 9 is then compressed, since this volume no longer has contact with the outlet opening 10, 11.Accordingly, by choosing the locations on which the drain openings 10, 11 are arranged, a corresponding ratio of the volume of fluid that is expelled to the volume of fluid that is compressed can be determined.

[0085] In addition to covering the drain openings 10, 11 with the spiral element 7, valve devices 13, as previously described in relation to Fig. 3-5, can be provided, for example for operating conditions in which the ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0086] Underload control is not required. In this case, the drain openings 10, 11 can be closed independently of the position of the spiral element 6, 7, so that the entire volume is compressed. Likewise, the drain openings 10, 11 can be closed even before they are covered by the spiral element 7, for example, to compress a larger proportion of the fluid.

[0087] Figures 10-15 show exemplary embodiments of thermal management systems 2, which may include a previously described scroll compressor 1. The embodiments according to Figures 10-13 differ in the design and / or positioning of a bypass line 16. As shown in Figure 10, a bypass can be created via a medium-pressure line 17 and the bypass line 16 into a low-pressure area, for example, to the inlet section 8. Figure 11 shows that the bypass line 16 can also be provided directly on the scroll compressor 1, for example, directly connecting the at least one outlet opening 10, 11 to the inlet section 8. Figure 12 shows a combination of the described embodiments of the bypass line 16, wherein the outlet opening 10, 11 can be connected to both the medium-pressure line 17 and the inlet section 8.For example, if the pressure introduced into the outflow line 12 via the medium-pressure line 17 is eliminated, an additional valve can be opened so that the connection of the bypass line 16 to the inlet section 8 or the low-pressure area is opened.

[0088] In Figures 10-12, an additional expansion valve 18 is arranged downstream of the condenser 3. This can be provided in addition to the expansion valve 4 to reduce the pressure in the high-pressure section to an intermediate pressure. The intermediate pressure is lower than the high pressure prevailing in the high-pressure section and higher than the low pressure in the low-pressure section. Figure 13 shows, in contrast, that the additional expansion valve 18 can also be arranged in the intermediate-pressure line 17.

[0089] In the embodiment of Fig. 14, it is shown that the valve assembly 13 connects the drain opening 10, 11 directly to the high-pressure line, namely before the additional ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0090] Expansion valve 18 can be connected, meaning downstream of condenser 3 in the flow direction. This can be used, for example, to control high pressure in the discharge line 12, as described previously. Fig. 15 shows an active valve that selectively connects the medium-pressure line to either the drain port 10, 11 or the drain port 10, 11 to the inlet section 8. This can be used, for example, to feed medium pressure into the discharge line 12 or to selectively connect the discharge line 12 to the inlet section 8.

[0091] As described, the thermal management system 2 and / or the scroll compressor 1 can be part of a motor vehicle not shown in detail. Furthermore, the method described herein can be carried out with the scroll compressor 1, as described. All details described herein are therefore also applicable to such a motor vehicle and the method described herein.

[0092] The advantages, details and features described in the individual embodiments can be combined, transferred to each other and interchanged with each other as desired.

[0093] ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26

[0094] Reference mark

[0095] 1 Scroll compressor

[0096] 2 Thermal management system

[0097] 3 Capacitor

[0098] 4 Expansion valve

[0099] 5 evaporators

[0100] 6, 7 spiral element

[0101] 8 Entrance section

[0102] 9 Interspace section

[0103] 10, 11 Drainage opening

[0104] 12. Exhaust pipe

[0105] 13 Valve assembly

[0106] 14 Valve element

[0107] 15 Check valve

[0108] 16 Bypass line

[0109] 17 Medium pressure line

[0110] 18 Expansion valve

Claims

ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26 Patent claims 1. Scroll compressor (1 ) for a thermal management system (2), in particular for a motor vehicle, comprising two spiral elements (6, 7) arranged at least sectionally nested within each other, which are movable relative to each other, wherein the scroll compressor (1 ) is configured to receive fluid in an inlet section (8) between the spiral elements (6, 7) and to compress it in at least one intermediate space section (9) between the spiral elements (6, 7) by means of the relative movement of the spiral elements (6, 7), characterized in that the scroll compressor (1 ) is configured to adjust a mass flow rate of the fluid compressed by the scroll compressor (1 ) independently of the rotational speed.

2. Scroll compressor (1 ) according to claim 1 , characterized in that at least one drain opening (10, 11 ) is arranged in the intermediate space section (9) and the scroll compressor (1 ) is designed to expel at least a part of the fluid from the drain opening (10, 11 ), particularly during a relative movement of the spiral elements (6, 7).

3. Scroll compressor (1 ) according to claim 1 or 2, characterized in that the at least one outlet opening (10, 11 ) is designed to reduce a maximum volume of fluid taken in through the inlet section (8) to an actual volume which actual volume is compressed in the scroll compressor (1 ).

4. Scroll compressor (1 ) according to one of the preceding claims, characterized in that the scroll compressor (1 ) is designed to discharge uncompressed fluid, in particular in an inlet area, or at least partially compressed fluid, in particular in a compression area, through the at least one outlet opening (10, 11 ).

5. Scroll compressor (1) according to one of the preceding claims, characterized in that at least one spiral element (6, 7), in particular the movable spiral element (7), is configured to carry the at least one ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26 to release the drain opening (10, 11) in a draining state and / or to close the at least one drain opening (10, 11) in a compression state and / or that the scroll compressor (1) has at least one valve device (13) configured to release the at least one drain opening (10, 11) in a draining state and / or to close the at least one drain opening (10, 11) in a compression state.

6. Scroll compressor (1 ) according to claim 5, characterized in that the valve assembly (13) has at least one valve element (14) connected to a high-pressure circuit and at least one check valve (15) connected to the drain opening (10, 11 ).

7. Scroll compressor (1 ) according to one of the preceding claims, characterized in that the scroll compressor (1 ) has a bypass line (16) which connects the at least one outlet opening (10, 11 ) to a low-pressure circuit, in particular to the inlet section (8).

8. Scroll compressor (1 ) according to one of the preceding claims, characterized in that the scroll compressor (1 ) has at least two outlet openings (10, 11 ) arranged opposite each other with respect to a center point and / or a central axis of the spiral elements (6, 7).

9. Thermal management system (2) comprising a scroll compressor (1) according to any of the preceding claims.

10. Motor vehicle comprising a scroll compressor (1) according to any one of claims 1 to 8 and / or a thermal management system (2) according to the preceding claim.

11. Method for operating a scroll compressor (1) for a thermal management system (2), in particular for a motor vehicle, comprising two spiral elements (6, 7) arranged at least partially nested within one another, which are relatively movable, wherein fluid in an inlet section (8) between ZF Friedrichshafen AG File 305260 Friedrichshafen 2024-09-26 the spiral elements (6, 7) are taken up and compressed by means of the relative movement of the spiral elements (6, 7) in at least one intermediate space section (9) between the spiral elements (6, 7), characterized in that a mass flow of the fluid compressed by the scroll compressor (1) is set independently of the rotational speed.

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