Control method for a compressed air supply system, control device, and vehicle

Abstract

The invention relates to a control method (2000, 4000, 5000) for a compressed air supply system (1200) with which a control device (1300) is associated, said method comprising the steps of: - the control device (1300) receiving (2100) a supply demand (BV), - the control device (1300) activating (2200) a compressed air generator (200) in order to provide compressed air (110) at a compressed air connection (1) when the control device (1300) receives a supply demand (BV), - the control device (1300) determining (2300) a freezing risk (RI) depending on environmental data (IU) and / or operating condition data (IB) for the compressed air generator (200), - the control device (1300) activating (2400) a main line switching valve (25) in order to block the pneumatic main line (12) in a first operating mode (B1) in the event that the freezing risk (RI) is below a predefined threshold value (W), - directing (2500) compressed air (141) through the branch line (14, 14.1, 14.2) to the compressed air supply connection (2) in the filling direction (B) in the first operating mode (B1) in order to supply the compressed air consumer (300). The invention also relates to a control device for carrying out the method and to a vehicle comprising such a control device.

Description

[0001] Control method for a compressed air supply system, control device and vehicle

[0002] The present invention relates to a control method for controlling a compressed air supply system for a vehicle, a control device for controlling a compressed air supply system and a vehicle having the same.

[0003] In vehicles, compressed air supply systems are used to supply compressed air to compressed air consumers. For this purpose, compressed air is supplied to the compressed air supply system via the compressed air connection by a compressed air source such as a compressor. Compressor and compressor are used synonymously in this description and usually refer to motor-driven units that compress air. Such a compressed air source, together with the compressed air supply system, forms a compressed air supply system. The control of such a compressed air supply system is preferably via an electronic control device or an electronic control unit (ECU). Such compressed air supply systems are also used, in particular, to supply compressed air to sensor cleaning devices as compressed air consumers.Preferably, such compressed air supply systems are designed to provide compressed air with an operating pressure of 5 bar and a volume flow of preferably 30-100 l / min.

[0004] Sensor cleaning systems for vehicles are also known. By means of a sensor cleaning system, surfaces on a vehicle, in particular sensor surfaces, can be cleaned using at least one cleaning fluid, for example, compressed air. By cleaning sensor surfaces on the vehicle, especially regularly, it can be achieved that sensors are less contaminated and therefore function more reliably. A clean sensor surface thus advantageously increases the reliability of driver assistance functions and / or semi-autonomous and / or autonomous driving functions of a vehicle. The safety of the vehicle, its occupants, and other road users is thus advantageously increased by a sensor cleaning system.

[0005] Sensor cleaning systems that use compressed air as a cleaning fluid are connected to a compressed air supply system as compressed air consumers. Drying of the compressed air supplied to the sensor cleaning system by the compressed air supply system is necessary to prevent corrosion and, at temperatures below freezing, frost-related damage and functional impairment to lines and the sensor cleaning system. The substrate in the air dryer is designed to adsorb moisture from the compressed air flowing through the air dryer, whereby the substrate can only adsorb moisture up to a maximum saturation point. To maintain the operation of the air dryer, the air dryer is usually regenerated – either regularly or at the latest when the saturation limit is reached.Regeneration, in this context, refers to the dehumidification of the substrate used for drying in the air dryer. To dehumidify the substrate, drier air than the substrate must be passed through the air dryer. This drier air binds some of the adsorbed moisture and thus reduces the substrate's saturation level. The operating time of the air dryer is limited by the saturation of the substrate in the air dryer. If the air dryer is not regenerated, reaching maximum substrate saturation requires the air dryer or the substrate in the air dryer to be replaced.

[0006] Compressed air supply systems for sensor cleaning devices face the challenge that the compressed air supplied at the compressed air supply connection cannot be returned to the compressed air supply system, but is instead expelled for cleaning the sensors. Thus, unlike in known compressed air supply systems, such as those described in DE 102017 010 772 A1, no compressed air already dried by the air dryer, which could be used to regenerate the air dryer, remains in the compressed air supply system.

[0007] The operating time of the compressed air supply system for sensor cleaning devices therefore depends significantly on the operating time of the air dryer and its saturation level. The required operating time of such a compressed air supply system can therefore currently only be achieved by increasing the substrate quantity – i.e., by using a larger air dryer. However, due to space constraints, such a solution is considered disadvantageous.

[0008] A compressed air supply system that overcomes these disadvantages is assigned a control device. The compressed air supply system further comprises a compressed air generator for providing compressed air at a compressed air connection, a pneumatic main line with an air dryer for drying and guiding compressed air to the compressed air supply connection in a filling direction, and a branch line branching off from the pneumatic main line upstream of the air dryer in the filling direction and reconnecting downstream of the air dryer. In the pneumatic main line of such a compressed air supply system, a pneumatic switching valve is arranged between the compressed air connection and the air dryer. This pneumatic switching valve is designed to open the pneumatic main line in a first operating mode so that flow can be pneumatically passed through it in the filling direction, and to close the pneumatic main line in a second operating mode.A branch line, which branches off from the main pneumatic line upstream of the air dryer and reconnects downstream of the air dryer, provides a bypass through which compressed air can be conveyed toward the compressed air supply connection. The switching valve can thus enable drying of the compressed air supplied at the compressed air supply connection as needed in the first operating mode and block it otherwise. In this way, the air dryer is, in a sense, "protected." Such a compressed air supply system takes advantage of the realization that extensive drying of the compressed air supplied at the compressed air supply connection is not permanently necessary, but may or may not be advisable depending on, among other things, the weather.

[0009] This is where the invention comes in. Its object is to provide a control method for controlling a compressed air supply system for a vehicle that overcomes at least one of the disadvantages known from the prior art. In particular, the object of the present invention is to provide a control method that enables control of the on-demand drying of the compressed air to be provided at the compressed air supply connection.

[0010] In a first aspect, the invention proposes a control method for solving the aforementioned problem. The control method for a compressed air supply system of the type described above comprises the steps:

[0011] Receiving a supply requirement from the compressed air consumer by the control device,

[0012] Controlling the compressed air generator, in particular an electric motor associated with the compressed air generator, by the control device to provide compressed air at the compressed air connection in the event that the control device receives a supply requirement,

[0013] Determining a freezing risk by the control device depending on environmental information and / or an operating state of the compressed air generator,

[0014] Control of a main line switching valve by the control device to block the pneumatic main line in a first operating mode in the event that the risk of freezing is below a predefined limit, and

[0015] Compressed air is fed through the branch line to the compressed air supply connection in the filling direction in the first operating mode to supply the compressed air consumer. According to the invention, the risk of freezing is understood to mean the risk of moisture contained in the compressed air supplied at the compressed air supply connection freezing.

[0016] The filling direction, as defined by the invention, refers to the direction of the compressed air flowing through a line from the compressed air connection to the compressed air supply connection. The pressurized line can be the main pneumatic line or a branch line designed to convey compressed air to the compressed air supply connection.

[0017] Such a control device preferably comprises one or more communicating control units. For example, a first control unit can be configured to control the compressed air consumer, a second control unit can be configured to control the compressed air supply system, and a third control unit can be configured to control the compressed air generator. Communication between such control units enables reliable data exchange and joint control of the compressed air supply system, as well as the compressed air consumer and the compressed air generator.

[0018] By blocking the pneumatic main line as needed in the first operating mode, the saturation of the air dryer is stopped if the risk of freezing is below a predefined limit. The predefined limit can be selected depending on the safety requirements of a given vehicle. For example, a high degree of autonomous driving of a vehicle requires increased safety requirements. With a lower degree of autonomous driving and the associated more moderate safety standards, a predefined limit can be set accordingly higher to further slow the saturation of the air dryer. In the first operating mode, in which the main line switching valve expediently blocks the pneumatic main line, no air to be dehumidified passes through the pneumatic main line in the filling direction of the air dryer.If, however, the risk of freezing exceeds this predefined limit, the control method ensures that the pneumatic main line is not blocked by the main line switching valve at that time, and compressed air is fed to the air dryer for drying. This ensures that freezing of lines or the compressed air consumer due to moisture in the compressed air provided at the compressed air supply connection is avoided. The invention particularly takes advantage of the finding that in some climates there is practically no risk of freezing. For example, if a vehicle is used in the tropics or subtropics with year-round temperatures well above freezing, there is normally no risk of freezing and the main line switching valve would block the pneumatic main line in the first operating mode.If this vehicle is now moved into the mountains, for example, the control method according to the invention suddenly determines an increased risk of freezing due to the changing environmental information, which would preclude the operation of the compressed air supply system in the first operating mode.

[0019] Further developments of the invention are specified in the dependent claims, which further develop the concept of the invention with regard to advantageous features within the scope of the task and with regard to further advantages.

[0020] Preferably, the method further comprises the steps of controlling the main line switching valve by the control device to release the pneumatic main line in a second operating mode in the event that the risk of freezing reaches or exceeds the limit value, as well as routing the pneumatic main line to the compressed air supply connection in a filling direction depending on the supply demand, and drying compressed air by the air dryer in the second operating mode. Thus, in the second operating mode, dried compressed air can be provided at the compressed air supply connection by the control method.

[0021] Depending on the design of the respective valve, controlling a switching valve to block a pneumatic line can be understood as either energizing or de-energizing the line. Similarly, controlling a switching valve to release a pneumatic line can be understood as either energizing or de-energizing the line, depending on the design of the respective valve.

[0022] Preferably, the control device is connected to a pneumatic arrangement associated with the compressed air supply connection. The method further preferably comprises controlling the pneumatic arrangement by the control device depending on sensor signals from a temperature sensor associated with the compressed air supply and / or the supply requirements of the air dryer.

[0023] The pneumatic arrangement preferably comprises a controllable throttle valve designed to throttle the compressed air supplied to the compressed air supply connection in the filling direction in the second operating mode. The compressed air supplied at the compressed air supply connection can thus be throttled to a permissible or required supply pressure, ensuring safe operation of the compressed air consumer.

[0024] The throttle valve preferably has a variable flow cross-section, wherein the control device controls the throttle valve to change the flow cross-section. The throttle valve influences the compressed air flow by changing the flow cross-section in the main pneumatic line. If the valve reduces the flow cross-section, this impedes the compressed air flow in the main pneumatic line, increasing the resistance to the compressed air flow. This, in turn, causes the pressure upstream of the throttle point to rise. The method thus throttles the pressure to the supply pressure by controlling the throttle valve, whereby the flow cross-section in the area of ​​the throttle valve is reduced and the compressed air is then released again.If the throttle valve is controlled by the control device according to the method, for example in the first operating mode, in such a way that a maximum cross-section reduction occurs, compressed air is no longer supplied to the supply connection. To throttle the volume flow, the throttle valve cooperates in particular with a pressure relief valve, such as a vent check valve arranged in the vent line, whereby the flow cross-section in the throttle valve is reduced until the back pressure upstream of the throttle valve reaches the pressure relief valve and provides sufficient pressure to open the valve. The vent check valve preferably opens at a pressure of at least 0.5 bar.By controlling the throttle valve in this way, the input volume flow provided at the compressed air connection can be divided into the supply volume flow for provision at the compressed air connection and an excess portion that is returned against the filling direction for regeneration of the air dryer.

[0025] The pneumatic arrangement further preferably comprises at least a first check valve opening in the filling direction and a bypass line branching off downstream of the check valve and connecting upstream of the check valve, with a second check valve opening in the return direction—i.e., opposite to the filling direction. The pneumatic arrangement further preferably comprises a throttle valve arranged in the bypass line downstream of the second check valve in the return direction, which is designed to throttle compressed air fed to the air dryer opposite to the filling direction. For this purpose, the throttle valve preferably has a throttle point with a variable flow cross-section. The throttle valve preferably has a control pressure line and is designed to regulate the flow cross-section depending on the control pressure.The control pressure line preferably connects to the bypass line downstream of the throttle point in the return direction - i.e., opposite to the filling direction. The first check valve is preferably arranged in the pneumatic main line, with the first check valve and the second check valve being arranged between the (first) air dryer and the compressed air supply connection. Alternatively or additionally, the first check valve is preferably arranged in the (second) branch line, with the first check valve and the second check valve being arranged between a second air dryer and the compressed air supply connection. In order to be returned in the branch line or the pneumatic main line, the compressed air must therefore inevitably pass through the controllable throttle valve, which is designed to throttle the pressure of the compressed air flowing to the respective air dryer.This compressed air is then preferably passed through a throttle located downstream of the air dryer in the filling direction, where it is further expanded. The resulting expansion of the compressed air allows it to absorb more moisture during the air dryer's regeneration.

[0026] Furthermore, the method preferably includes the on-demand activation of an additional compressed air source depending on the supply requirement and / or a sensor signal from a temperature sensor assigned to the compressed air source. Thus, an additional compressed air source is activated in addition to the compressed air source. An additional compressed air source increases the available compressed air quantity, i.e., the available volumetric flow, and allows for response to varying system requirements. An increased supply requirement in relation to the supply volumetric flow can occur, for example, if all nozzles of a sensor cleaning device need to be supplied with compressed air.Because the control unit can switch on an additional compressed air source depending on this supply requirement, it is possible to respond to such supply requirements and provide a sufficient supply volume flow with the supply pressure to supply all nozzles. Furthermore, it may be necessary to switch off the compressed air supply in the event of impending overheating. By switching on the compressed air source depending on the sensor signals from the temperature sensor monitoring the compressed air supply, it is possible to respond to such impending overheating and continue to maintain the operation of the compressed air supply system via the compressed air source.

[0027] More preferably, determining the risk of freezing further comprises determining and / or retrieving the environmental information by the control device. The environmental information can, for example, be determined directly via the control device using sensors or retrieved via a signal line or data interface, such as in particular a bus, from an on-board network or another storage device. Retrieving the environmental information via the Internet or other communication services is also within the scope of the invention. The environmental information preferably comprises one, several or all of the following: a current ambient temperature, a current ambient humidity, a climate zone, an average temperature, an average ambient humidity. The environmental information is preferably determined at a current location and / or along a route and / or at a destination.

[0028] Determining the environmental information preferably comprises retrieving location information regarding the route and / or the destination from an on-board network connected via a data interface and / or a navigation system. Alternatively or additionally, retrieving the environmental information comprises retrieving location information regarding the route and / or the destination from an on-board network connected via a data interface and / or a navigation system. The control device can thus also consider future situations that influence the supply requirements and, in particular, the permissible air humidity of the compressed air at the compressed air supply connection.If, for example, a temperature below freezing is forecast at the destination, the pneumatic main line will be opened early on, based on the resulting predictable future supply demand, to provide dry compressed air at the compressed air supply connection. This provides predictive control and a control method with increased operational reliability.

[0029] The method preferably comprises retrieving location information regarding the route and / or the destination, and retrieving environmental information associated with the location information by the control device from a signal-conductingly connected on-board network and / or a navigation system. By retrieving location information and environmental information, such as temperature or humidity, predicted temperatures and / or humidity of the environment can be determined. This enables predictive control of the compressed air supply system.

[0030] It is further preferred that the temperature and / or humidity comprise a current temperature and / or humidity of the environment, wherein the method comprises the control device retrieving the current temperature and / or humidity from at least one signal-conductingly connected ambient temperature sensor and / or humidity sensor or from a signal-conductingly connected on-board electrical system. By retrieving the current temperature, a regeneration requirement can be reliably identified depending on the current ambient conditions. In particular, fluctuations compared to, for example, an average temperature or a predicted temperature are taken into account in this way. An ambient temperature sensor or a humidity sensor can detect such a temperature or humidity directly in the environment of the vehicle.An on-board network can also retrieve this temperature and / or humidity from signal-conducting ambient temperature sensors or humidity sensors, or retrieve the temperature from nearby weather stations or from the Internet, particularly via wireless data connections.

[0031] The control device preferably has a memory and is designed to retrieve information relating to the temperature and / or air humidity or state variables during the operating period of the air dryer. Further preferably, the control device is designed to retrieve information from a dew point sensor to determine the risk of freezing. Further preferably, the risk of freezing is below the predefined limit value if at least one of the following conditions with regard to the environmental information is met: the air humidity of the environment is below 2 g / m3, the temperature of the environment is above 15°C, the dew point temperature of the environment is more than 15°C below the ambient temperature, the average temperature is at least 20°C, the average air humidity is at most 0.5 g / m3, in particular at most 0.25 g / m3, the climate zone is tropical or subtropical.

[0032] The operating state information preferably comprises one, several or all of the following: an operating time of the compressed air generator, in particular within a predetermined time period, preferably of the electric motor, which is monitored by the control device via a signal-conducting connection, in particular via a CAN bus connection, a temperature of the compressed air generator, in particular of the electric motor, which is measured directly or indirectly by at least one sensor and monitored by the control device, a pressure in the pneumatic main line during operation of the compressed air generator.

[0033] If the dew point temperature of the environment is more than 15°C below the ambient temperature, the ambient air can cool by 15°C without condensation occurring.

[0034] The average temperature is a predefined annual average temperature or a monthly average temperature, particularly determined by weather services. Thus, temperatures do not need to be continuously recorded or retrieved. The average humidity is a predefined annual average humidity or a monthly average humidity, particularly determined by weather services. Thus, the humidity does not need to be continuously recorded or retrieved.

[0035] The temperature of the compressed air supplied to the compressed air connection by the compressed air supply depends largely on the operating time and the pressure in the main pneumatic line. If a certain operating time is exceeded, the compressed air supplied to the compressed air connection will still have a sufficiently high temperature, even after being routed through the branch line at the compressed air supply connection, so that freezing of the lines or the compressed air consumer is virtually impossible. In such a case, the control method determines a freezing risk below the predefined limit value depending on the operating state, which is largely determined by the operating time of the compressed air supply. Alternatively or additionally, the operating state can also be measured directly or indirectly by directly determining the temperature of the compressed air supply using at least one sensor and thus monitored by the control device.Depending on this temperature, which characterizes the operating state, the risk of freezing can be reliably determined by means of the control method according to the invention.

[0036] More preferably, the risk of freezing is below the predefined limit value if at least one of the following conditions with regard to the operating state information is met: the operating time of the compressed air generator within 15 minutes is at least 5 minutes, the temperature of the compressed air generator is at least 60°C.

[0037] With such a long operating time, the supplied compressed air must be expected to have sufficiently high temperatures to rule out any risk of freezing. The same applies to a compressed air supply temperature of 60°C. In these cases, the risk of freezing is so low that the compressed air supply system can be operated in the first operating mode with a high degree of operational reliability. Furthermore, the method preferably comprises controlling a branch line switching valve to block the branch line in the filling direction in the event that the risk of freezing exceeds the predefined limit. By blocking the branch line, incompletely dried compressed air is prevented from reaching the compressed air supply connection. Mixing of the compressed air from the pneumatic main line and the branch line is thus avoided.

[0038] By pre-filling the pneumatic main line, an increased compressed air supply can be provided at the compressed air supply connection at the start of the compressed air supply in the event that the control device receives a supply requirement, for example in order to be able to remove heavy contamination by the sensor cleaning device.

[0039] According to a preferred embodiment, the branch line is a first branch line with a first branch line switching valve, and the compressed air supply system further comprises a second branch line with a second branch line switching valve and a second air dryer. Preferably, the control device monitors a saturation level of the first air dryer and preferably of the second air dryer, the method further comprising the steps:

[0040] Controlling the second branch line switching valve by the control device to release the second branch line in a third operating mode in the event that the freezing risk reaches or exceeds the limit value and the saturation level of the first air dryer reaches a maximum saturation level,

[0041] Feeding compressed air through the second branch line to the compressed air supply connection in a filling direction depending on the supply requirement, and drying compressed air by the air dryer in the third operating mode. This allows the operational readiness of the compressed air supply system to be further increased, and an operational readiness of up to 100% can be achieved even at temperatures below freezing. This is particularly important for autonomous vehicles, since the functionality of sensors is crucial for the safety of occupants and the environment. The control method according to the invention for a compressed air supply system of the type described above maintains a reliable compressed air supply with dried compressed air even when a saturation limit of a first air dryer is reached.

[0042] It should be understood that the branch line switching valve can be arranged at a branch point where the branch line branches off from the main pneumatic line and can be designed as a 3 / 2-way valve. Thus, the branch line switching valve designed as a 3 / 2-way valve combines the functions of the main line switching valve and the branch line switching valve. The distribution of the compressed air partially dehumidified by the water separator can be controlled with just one switching valve.

[0043] More preferably, the method comprises the following step:

[0044] Flushing the pneumatic main line and / or the branch line by means of compressed air provided at the compressed air connection and discharging the compressed air via the vent line, wherein the compressed air is preferably dried by the air dryer and the flushing of the pneumatic main line is carried out against the filling direction and / or the flushing of the branch line is carried out in the filling direction, and / or

[0045] Flushing the compressed air receiver with compressed air provided at the compressed air connection and preferably dried by the air dryer and discharging the compressed air via the compressed air receiver.

[0046] Flushing the pneumatic main line and / or branch line removes residues, particularly water accumulation, from the lines, and, in particular, allows air with a high moisture content to be released from the compressed air supply system via the vent line to the vent connection. Flushing the compressed air receiver with dried compressed air ensures that moisture does not freeze in the compressed air receiver during extended downtimes, even if the receiver was previously operated with only partially dehumidified or moist compressed air. However, if flushing is generally performed with compressed air that has not been dried by an air dryer, moisture accumulation in valves can be blown out.

[0047] By flushing the pneumatic main line and / or the branch line, residues in the lines can be removed and, in particular, air with an increased moisture content can be released from the compressed air supply system via the vent line to the vent connection.

[0048] More preferably, the method comprises the following step:

[0049] Control of the main line switching valve and the branch line switching valve for pneumatically decoupling the pneumatic main line and the branch line from the compressed air connection. In particular, the air dryer located in the pneumatic main line is also pneumatically decoupled from the compressed air supply. By pneumatically decoupling the pneumatic main line or the branch line from the compressed air connection, the system is depressurized into a standby mode in which neither compressed air is supplied to the compressed air supply connection nor is the air dryer regenerated. In this way, the saturation of the air dryer is stopped and the branch line and the pneumatic main line are protected against possible later frost-related damage. This takes into account that the ambient conditions can change, for example, when a vehicle is parked.For example, nighttime frost could otherwise cause frost damage, which is prevented in this way. Preferably, the method further comprises controlling the vent valve to pneumatically decouple the vent line from the environment. Thus, the vent line is also protected in standby mode.

[0050] The method further preferably comprises controlling a first shut-off valve arranged downstream of the first air dryer in the filling direction to block the pneumatic main line in the first operating mode in the event that the risk of freezing is below the predefined limit, and / or controlling a second shut-off valve arranged downstream of the second air dryer in the filling direction to block the second branch line in the first operating mode in the event that the risk of freezing is below the predefined limit. The pneumatic main line is thus blocked both in the filling direction and against the filling direction in the first operating mode, so that the air dryer is protected from still-moist compressed air and progressive saturation of the air dryer is avoided.

[0051] In embodiments in which the air dryer in the pneumatic main line is a first air dryer, the shut-off valve is accordingly arranged in the pneumatic main line downstream of the first air dryer in the filling direction. The air dryer or the first air dryer is thus pneumatically decoupled from the branch line. When the compressed air supply system is operated in the first operating mode, in which the compressed air is provided exclusively via the branch line at the compressed air supply connection, no still moist compressed air reaches the air dryer and promotes its saturation. Such a shut-off valve is preferably a switchable shut-off valve, particularly preferably an electrically controllable 2 / 2-way valve. In addition, such pneumatic decoupling of the air dryer from the branch line carrying moist compressed air enables a more precise prediction of the saturation level of the respective air dryer.

[0052] The control method preferably further comprises controlling the first branch line switching valve and / or controlling the second branch line switching valve to block the second branch line in the second operating mode and / or controlling the first branch line switching valve to block the first branch line in a third operating mode in which the compressed air is guided via the second branch line. This ensures that in the second operating mode or in the third operating mode, the compressed air reaches the compressed air supply connection exclusively via the respective air dryer and does not mix with the still moist compressed air from the second branch line. The control method preferably further comprises regulating the supply pressure and / or the supply volume flow of the compressed air provided at the compressed air supply connection by the control device depending on the supply requirement.The control method thus extends the function of the control device beyond simply receiving the supply pressure and / or the supply volume flow at the compressed air supply connection to include the regulation of the supply pressure and / or the supply volume flow at the compressed air supply connection. The control device is connected in a signal-conducting manner to at least one pressure sensor arranged in the pneumatic main line for providing sensor signals and to a pressure regulator assigned to the pneumatic main line and / or the compressed air connection, wherein the control device controls the pressure regulator depending on the sensor signals. The pressure regulation or the regulation of the supply volume flow thus takes place depending on the pressure in the pneumatic main line, which connects the compressed air connection to the compressed air supply connection. The control device can thus react directly to pressure fluctuations in the pneumatic main line.

[0053] Additionally or alternatively, the control device is preferably connected in a signal-conducting manner to the electric motor, in particular the BLDC electric motor, and is designed to regulate a motor speed of the electric motor in order to provide compressed air with the supply pressure and / or the supply volume flow at the compressed air supply connection. Thus, the control of the supply pressure and / or the supply volume flow can optionally also be carried out by controlling the motor speed of the electric motor driving the compressor. Such control of the motor speed also enables indirect pressure control due to the direct influence on the performance of the compressor. Furthermore, the saturation of the air dryer is generally limited by controlling the motor speed or pressure control, since the inlet pressure at the compressed air connection is preferably limited to 5 bar by pressure control.Furthermore, the compressed air supply system preferably further comprises a compressor vent line with a compressor vent valve. The method preferably comprises controlling the compressor vent valve to vent a line volume between the compressed air supply and the branch line switching valve and the main line switching valve. The starting resistance for the compressor is thus reduced.

[0054] Preferably, one, several or all of the following are designed as normally closed solenoid directional control valves: the at least one main line switching valve, the at least one branch line switching valve, at least one nozzle valve of a sensor cleaning device connected to the compressed air supply system, the at least one vent valve, and the compressor vent valve, wherein the solenoid directional control valves have a coil for generating a magnetic force and an armature which can be moved by the magnetic force against a spring force acting in the direction of a valve seat, and are designed to be moved away from the valve seat by being energized with an opening control current against the spring force and to rest against the valve seat by being energized with a heating control current which is smaller than the opening control current, wherein the coil is designed to heat the solenoid directional control valve when the heating control current is applied.The ability to heat these valves reduces the risk of frost damage to the pneumatic system as a whole. This applies not only to the sensor cleaning device and other compressed air consumers, but also, in particular, to the compressed air supply system.

[0055] Preferably, the method further comprises selectively energizing one, several or all of the following solenoid directional control valves with an opening control current and a heating control current: the at least one main line switching valve, the at least one branch line switching valve, at least one nozzle valve of a sensor cleaning device connected to the compressed air supply system, the at least one vent valve, and the compressor vent valve.

[0056] The ability to heat the aforementioned valves reduces the overall risk of malfunctions in the pneumatic system due to freezing. This applies not only to the sensor cleaning device and other compressed air consumers, but also, in particular, to the compressed air supply system. Using the solenoid valves' existing coil eliminates the need for additional heating elements. It should be understood that heating the solenoid valves is particularly necessary before opening, as they remain closed for extended periods of time. Damage to the valve only occurs when a possibly frozen valve or its armature is moved. Energizing the solenoid valve before it actually opens prevents it from freezing by heating the valve, which is preferably maintained permanently during operation.

[0057] A heated nozzle valve reduces the risk of frost damage at temperatures close to freezing. The threshold at which only compressed air dried by the air dryer may be fed to the compressed air supply connection is therefore shifted to lower temperatures.

[0058] Furthermore, the risk of freezing is determined by the control device depending on the ambient information in such a way that, in the event that the control device is configured to apply a heating control current, a reduced risk of freezing is determined. Preferably, the risk of freezing is below the predefined limit value in the event that the ambient temperature is at least 0°C, in particular at least 5°C, and the at least one nozzle valve and the at least one vent valve are heated by being energized with the heating control current. The area of ​​application in which the provision of compressed air via the branch line of the compressed air supply system is sufficient can thus be extended to lower temperatures.

[0059] In general, it is advantageous to determine the freezing risks for each switching valve or valve group individually. The freezing risk can be defined in the following order from low to high. The risk is measured by the probability that the switching valve will come into contact with a quantity of water that could cause freezing:

[0060] - switching valves of the compressed air consumer,

[0061] - Main line and branch line switching valves,

[0062] - vent valves.

[0063] Depending on the determined freezing risks, the heating control current is then applied to the respective switching valves or valve groups.

[0064] The invention solves the aforementioned problem in a second aspect by a control device according to claim 19. According to the second aspect, the invention proposes a control device for controlling a compressed air supply system for a vehicle, in particular a passenger car. The control device is assigned to the compressed air supply system for supplying a compressed air consumer via a compressed air supply connection, and the compressed air supply system comprises a compressed air generator for providing compressed air at a compressed air connection, a pneumatic main line with an air dryer for drying and guiding compressed air to the compressed air supply connection in a filling direction, and a branch line branching off from the pneumatic main line upstream of the air dryer in the filling direction and reconnecting downstream of the air dryer.The control device is designed to receive a supply requirement from the compressed air consumer and to control the compressed air supply, and is connectable to the compressed air consumer and the compressed air supply in a signal-conducting manner. Furthermore, the control device is designed to determine a freezing risk based on environmental information and / or operating status information from the compressed air supply and to control a main line switching valve to block the pneumatic main line in a first operating mode in the event that the freezing risk is below a predefined limit.

[0065] The control device is thus particularly designed to carry out a control method according to the first aspect of the invention. Advantages and preferred embodiments described with reference to the first aspect are thus also advantages and preferred embodiments of the control device according to the second aspect of the invention.

[0066] The invention solves the aforementioned problem in a third aspect by a vehicle according to claim 20. According to the third aspect, the invention proposes a vehicle, in particular a passenger car, with a compressed air supply system for supplying a compressed air consumer via a compressed air supply connection. The compressed air supply system comprises a compressed air generator for providing compressed air at a compressed air supply connection, a pneumatic main line with an air dryer for drying and guiding compressed air to the compressed air supply connection in a filling direction, and a branch line branching off from the pneumatic main line upstream of the air dryer in the filling direction and reconnecting downstream of the air dryer.Furthermore, the vehicle comprises a control device according to the second aspect of the invention assigned to the compressed air supply system and a compressed air consumer, in particular a sensor cleaning device connected to the compressed air supply connection. Such a control device enables the vehicle to benefit from the advantages described in relation to the first aspect and the second aspect of the invention. Preferred embodiments and advantages according to the first aspect of the invention are likewise preferred embodiments and advantages of the vehicle according to the third aspect of the invention, and vice versa.

[0067] The vehicle preferably further comprises at least one sensor and / or a data interface, preferably a bus, in particular a CAN bus, which is signal-conductingly connected to the control device and is designed to provide sensor and / or memory data for determining a saturation level of the air dryer and / or a humidity defined by at least one state variable. Thus, the controller can retrieve necessary information regarding the saturation level of the air dryer and / or a humidity or temperature either directly via at least one sensor or via a corresponding data interface. This information, in particular, enables a calculation or estimation of the saturation level of the air dryer.The ambient humidity, which is sucked in and compressed by the compressed air supply, in particular a compressed air supply, ultimately also influences the permissible moisture content of the compressed air provided at the compressed air connection and consequently also the saturation of the air dryer.

[0068] More preferably, the vehicle further comprises an on-board electrical system which is connected to the control device via the data interface and is designed to provide one, several or all of the following data: location information of a navigation system, memory data of an on-board electrical system memory, sensor information of at least one sensor connected to the on-board electrical system, in particular an ambient temperature sensor and / or a humidity sensor and a compressed air sensor. Furthermore, the vehicle preferably comprises an on-board electrical system battery which is designed to provide a power supply for the on-board electrical system and / or the compressed air consumer and / or the control device and / or the compressed air transmitter. Thus, a power supply for the components of the vehicle relating to the supply and control of the compressed air supply system is provided centrally via the on-board electrical system battery.The invention advantageously takes into account the fact that, for example, the compressed air generator requires an increased energy requirement to compress the sucked-in compressed air.

[0069] Sensor information in this case includes a temperature which is measured by a

[0070] temperature sensor and / or a pressure that was detected by a pressure sensor and / or a humidity that was detected by a humidity sensor.

[0071] Accordingly, a central power supply for the compressed air receiver via the vehicle's battery is also advantageous. The compressed air supply system itself, or the electrically controlled pneumatic solenoid valves, are preferably supplied with power via the control unit. Such a power supply or de-energization by the control unit can preferably be used to control the pneumatic switching valves.

[0072] Further preferably, the control device is designed to determine, depending on the provided data, the current and / or predicted ambient temperature and / or the current and / or predicted ambient humidity at at least one of the following positions: at a current location, along a route, and at a destination. A suitably designed control device can thus determine the ambient temperature and / or humidity not only at a current location, but also proactively along the route or at a destination. This enables proactive regeneration of the air dryer, taking future ambient conditions into account. Such ambient conditions can, in particular, relate to low temperatures or very high air humidity.For example, high ambient humidity leads to increased saturation, or low temperatures require the air dryer to be ready for operation.

[0073] Embodiments of the invention are now described below with reference to the drawings in comparison to the prior art, some of which is also shown. These are not necessarily intended to represent the embodiments to scale; rather, where useful for explanation, the drawings are schematic and / or slightly distorted. With regard to additions to the teachings immediately apparent from the drawings, reference is made to the relevant prior art. It should be noted that many modifications and changes to the form and detail of an embodiment can be made without departing from the general idea of ​​the invention. The features of the invention disclosed in the description, the drawings and the claims can be essential for further development of the invention, both individually and in any combination.Furthermore, all combinations of at least two of the features disclosed in the description, the drawings, and / or the claims fall within the scope of the invention. The general idea of ​​the invention is not limited to the exact form or detail of the preferred embodiment shown and described below, nor is it limited to an object that would be limited compared to the object claimed in the claims. In the case of specified dimensioning ranges, values ​​within the stated limits are also intended to be disclosed as limit values ​​and can be used and claimed as desired.

[0074] Further advantages, features and details of the invention will become apparent from the following description of the preferred embodiments and from the drawing, which shows:

[0075] FIG. 1 shows a compressed air supply system with an associated control device according to the invention in a perspective view;

[0076] FIG. 2a shows a vehicle with a compressed air supply system schematically in a first operating mode in a first embodiment;

[0077] FIG. 2b shows the vehicle according to FIG. 2a with the compressed air supply system schematically in a second operating mode in a first embodiment;

[0078] FIG. 3 shows a vehicle with a compressed air supply system schematically in a first operating mode in a second embodiment; FIG. 4 shows a vehicle with a compressed air supply system schematically in a first operating mode according to a third embodiment;

[0079] FIG. 5 shows a solenoid directional control valve for a vehicle according to FIGS. 2a to 4;

[0080] FIG. 6a shows a first embodiment of a pneumatic arrangement;

[0081] FIG. 6b shows a second embodiment of a pneumatic arrangement;

[0082] FIG. 6c shows a third embodiment of a pneumatic arrangement;

[0083] FIG. 6d shows a fourth embodiment of a pneumatic arrangement;

[0084] FIG. 7 shows the sequence of a method for the control device 1300 of a compressed air supply system for a vehicle according to FIGS. 2a and 2b according to a first embodiment;

[0085] FIG. 8 shows the sequence of a method for the control device 1300 of a compressed air supply system for a vehicle according to FIG. 3 according to a second embodiment; and

[0086] FIG. 9 shows the sequence of a method for the control device 1300 of a compressed air supply system for a vehicle according to FIG. 4 according to a third embodiment.

[0087] The compressed air supply system 1200 according to FIG. 1 comprises a compressed air supply system 100. Furthermore, the compressed air supply system 1200 comprises a compressed air generator 200, which preferably comprises a compressor 201 driven by an electric motor 203.

[0088] The compressed air supply system 1200 is connected to the compressed air generator 200 via a compressed air connection 1 (see FIGS. 2a and 2b). The compressed air supply system 100 comprises an air dryer 5 arranged in a pneumatic main line 12 (see FIGS. 2a and 2b) and a water separator 6 (see FIGS. 3 and 4) arranged fluidically between the air dryer 5 and the compressed air connection 1 (see FIGS. 2a and 2b). Furthermore, the compressed air supply system 100 comprises a pressure control module 101, which has a number of main line switching valves (not shown) for distributing the pressure within the compressed air supply system 100.

[0089] The compressed air supply system 1200 is assigned a control device 1300 for controlling the compressed air supply system 1200.

[0090] An ambient temperature sensor 410 and a humidity sensor 400 are preferably connected in a signal-conducting manner to the control device 1300. These sensors are designed to provide sensor information S, T, H for determining a saturation level G (see FIG. 8) of the air dryer 5 and / or a permissible humidity Hmax (see FIG. 8). Alternatively or additionally, a dew point sensor (not shown) for determining the saturation level G (see FIG. 8) of the air dryer 5 can also be connected to the control device.

[0091] Furthermore, at least one data interface 70, preferably a bus 71, in particular a CAN bus 72, is preferably connected to the control device 1300 in a signal-conducting manner and is designed to provide stored or determined sensor information S, T, H for determining a saturation level G (see FIG. 8) of the air dryer 5 and / or a permissible humidity Hmax (see FIG. 8). For this purpose, the data interface 70 connects the control device 1300 to an on-board electrical system 1600 or a navigation system 1700. Alternatively, the connection to the navigation system 1700 can also be made indirectly via the on-board electrical system 1600, wherein the on-board electrical system 1600 retrieves location information IGPS (see FIG. 7) from the navigation system 1700. The on-board electrical system 1600 preferably comprises an on-board electrical system memory 1610, in which the sensor information S, T, H is stored.

[0092] The on-board electrical system 1600 further comprises an on-board electrical system battery 1620, which is designed to supply the on-board electrical system 1600 and / or the compressed air generator 200 and / or the compressed air receiver 300 (cf. FIGS. 2a, 2b, 3, 4) and / or the control device 1300 with current I.

[0093] The operation of the control device 1300 is explained in detail in connection with the preferred embodiments of the vehicle 1000 shown in FIGS. 2a, 2b and 3.

[0094] FIG. 2a shows a vehicle 1000, in particular a passenger car 1100. The passenger car 1100 comprises a compressed air supply system 1200 as well as an electronic control unit 1300 (ECU) and a compressed air collector 300, which in this case is a sensor cleaning device 301.

[0095] The compressed air supply system 1200 comprises a compressed air supply system 100 and a compressed air generator 200 connected to the compressed air supply system 100 via a compressed air connection 1. The compressed air generator 200 here comprises a compressor 201 with an electric motor 203.

[0096] The compressed air supply system 100 comprises a compressed air connection 1 for connection to the compressed air generator 200 (see FIG. 1) and a compressed air supply connection 2 for connecting the compressed air consumer 300. The compressed air connection 1 is connected to the compressed air supply connection 2 via a pneumatic main line 12. From the pneumatic main line 12, a vent line 13 also leads to a vent connection 3, which is configured to vent the pneumatic main line 12. The compressed air supply system 100 further has an air dryer 5 arranged in the pneumatic main line 12. The air dryer 5 is configured to dry the compressed air 110 provided at the compressed air connection 1 and guided through the pneumatic main line 12 in a filling direction B (not shown, see FIG. 2b).

[0097] The compressed air supply system comprises a vent valve assembly 23. A vent valve 23.1 of the vent valve assembly 23 is arranged in the vent line 13, which is preferably an electrically controllable 2 / 2-way valve. Furthermore, a vent check valve 23.2 of the vent valve assembly 23 is preferably arranged downstream of the vent valve 23.1 in the direction of the vent line 3, which preferably opens in a pressure-controlled manner toward the vent connection 3. When the vent valve 23.1 is open, the vent check valve 23.2 thus preferentially opens the vent line 13 due to the compressed air in the vent line 13. At the same time, the vent check valve 23.2 prevents moisture from entering the vent line 13.It should also be understood that the vent line 13 can branch off from the main line 12 at any desired position, but preferably between the main line switching valve 25 and the air dryer 8.

[0098] Advantageously, the compressed air supply system 100 further comprises a throttle 8. The throttle 8 is preferably arranged downstream of the air dryer 5 in the filling direction B. The throttle 8 is configured to expand the compressed air that may be returned for the regeneration of the air dryer 5.

[0099] Upstream of the air dryer 5, a branch line 14 also branches off from the pneumatic main line 12, which connects back to the pneumatic main line 12 between the air dryer 5 and the compressed air supply connection 2.

[0100] Furthermore, a pneumatic switching valve 25 is arranged in the pneumatic main line 12 in the filling direction B (see FIG. 2b) downstream of the branching branch line 14 and upstream of the air dryer 5. The control device 1300 is designed to control the main line switching valve 25 for selectively enabling and blocking the pneumatic main line downstream of the branching branch line 14. Preferably, the compressed air supply system 100 further comprises a branch line switching valve 24 arranged in the branch line 14. The control device 1300 is designed to control the branch line switching valve 24 for selectively enabling and blocking the branch line 14. Furthermore, the control device 1300 is designed to control the vent valve 23.1 for selectively enabling and blocking the vent line 13. The compressed air supply system 100 has the pressure control module 101 shown in FIG. 1.The pressure control module 101 is preferably assigned the main line switching valve 25, the branch line switching valve 24 and the vent valve arrangement 23, the vent valve 23.1.

[0101] The branch line switching valve 24 can only be provided optionally, wherein the compressed air supply system can also be operated only with the main line switching valve 25 and the vent valve 23.1, in particular the vent valve arrangement 23.

[0102] Furthermore, the compressed air supply system 100 comprises a pressure sensor 9, which is arranged in the pneumatic main line 12. The pressure sensor 9 is configured to detect an inlet pressure P in the pneumatic main line 12, i.e., the pressure of the moist compressed air 110 provided at the compressed air connection 1, and to provide a sensor signal S. The pressure sensor 9 is connected in a signal-conducting manner via a first signal line S1 to the control unit 1300, which is thus configured to monitor the inlet pressure P.

[0103] The control device 1300 is further connected to the main line switching valve 25 in the pneumatic main line via a second signal line S2 and to the vent valve 23.1 via a third signal line S3. Preferably, the branch line switching valve 24 is connected to the control device 1300 via a fourth signal line S4.

[0104] The control device 1300 is further connected to the compressed air receiver 300 via a fifth signal line S5.

[0105] Furthermore, the control device 1300 is connected to the compressed air supply 200 via a sixth signal line S6. The control device 1300 is configured to monitor an operating time tß of the compressed air supply 200, which in this case comprises a compressor 201 with an electric motor 203. Furthermore, the control device 1300 is configured to monitor a motor speed M as operating state information IB (see FIG. 7) of the electric motor 203. The electric motor 203 is preferably a BLDC electric motor 204 (see FIG. 1).

[0106] The signal lines S1, S2, S3, S4, S5, and S6 can be either wired or wireless. Preferably, the signal lines S5 and S6 each comprise a data interface, in particular a bus or CAN bus. The signal lines S2, S3, and S4 can preferably also be merely electrical lines, through which the control device 1300 controls the main line switching valve 25, the branch line switching valve, and the vent valve 23.1 by energizing or de-energizing them.

[0107] Furthermore, the control device 1300 is preferably designed to regulate a supply pressure Pv and / or a supply volume flow Vv of the compressed air 120' provided at the compressed air supply connection 2 (see FIG. 2b). To regulate the supply pressure Pv and / or the supply volume flow Vv, the control device 1300 is signal-conductingly connected to the pressure sensor 9 arranged in the pneumatic main line 12, wherein the pressure sensor 9 is designed to detect the inlet pressure P in the pneumatic main line 12. Preferably, a pressure regulator 40 (see FIG. 3) is further assigned to the compressed air connection 1, and the control device 1300 is designed to control the pressure regulator 40 to regulate the supply pressure Pv and / or the supply volume flow Vv depending on the sensor signals S of the pressure sensor 9 (see FIGS. 7-9).

[0108] Alternatively or additionally, the control device 1300 is connected to the electric motor 203 via the sixth signal line S6 and is designed to regulate a motor speed M of the electric motor 203 for providing compressed air 120' with the supply pressure Pv and / or the supply volume flow Vv at the compressed air connection 1. The vehicle 1000 further comprises an on-board electrical system 1600, which is connected to the control device 1300 in a signal-conducting manner via an eighth signal line S8.

[0109] FIG. 2a shows the compressed air supply system 1200 in a first operating mode B1. In the first operating mode B1, the control device 1300 is configured to actuate the main line switching valve 25 to block the pneumatic main line 12. The main line switching valve 25 is configured here as a normally closed 2 / 2-way valve, so that the main line switching valve 25 blocks the pneumatic main line 12 in the de-energized state. The compressed air 110 provided at the compressed air connection 1 is thus guided exclusively via the branch line 14 in the filling direction B, i.e., from the compressed air connection 1 to the compressed air supply connection 2. The control device 1300 is further designed to control the vent valve 23.1, which is also preferably designed as a normally closed 2 / 2-way valve, in the first operating mode B1 to block the vent line 13.In the first operating mode B1, no compressed air flows through the air dryer 5 in the filling direction B, so that its saturation does not progress any further. The control device 1300 is designed to correspondingly control the main line switching valve 25 in the event that a freezing risk Ri (see FIG. 7-9) is below a predefined limit value W (see FIG. 7-9), wherein the control device 1300 is designed to determine this freezing risk Ri (see FIG. 7-9). In other words, the control device 1300 controls the main line switching valve 25 in the event that freezing of the residual moisture in the compressed air to be provided at the compressed air supply connection 2 is highly unlikely, so that dehumidification of this compressed air by the air dryer 5 is not necessary.

[0110] FIG. 2b shows the compressed air supply system 1200 in a second operating mode B2. The main line switching valve 25 is configured, as a result of the control by the control device 1300, to open the pneumatic main line 12 so that flow can pass through it in the filling direction B, so that compressed air 110 can be guided from the compressed air connection 1 in the pneumatic main line 12 to the air dryer 5, from where it can be dried to form compressed air 120. The dried compressed air 120' then passes through the throttle 8 and is provided at the compressed air supply connection 2. The control device 1300 is designed to control the main line switching valve 25 accordingly in the event that a freezing risk Ri (see FIG. 7-9) reaches or exceeds the predefined limit value W (see FIG. 7-9), wherein the control device 1300 is designed to determine this freezing risk Ri (see FIG. 7-9).In this case, drying of the compressed air to be provided at the compressed air supply connection 2 by the air dryer 5 is necessary in order to reliably prevent the residual moisture of the compressed air from freezing, for example within the compressed air receiver 300.

[0111] Preferably, the branch line switching valve 24 is provided in the branch line 14, wherein the control device 1300 is configured in the second operating mode B2 to control the branch line switching valve 24 to block the branch line 14. In the event that the branch line 14 does not have a branch line switching valve 24, a compressed air flow comprising dried compressed air 121' from the pneumatic main line 12 and humidified compressed air 141 (cf. FIG. 4) from the branch line 14 is provided at the compressed air supply connection 2 in the second operating mode B2.

[0112] The vent valve 23.1 is also designed to block the vent line 13 in the second operating mode B2.

[0113] FIG. 3 shows a second embodiment of the vehicle 1000 according to the invention. Identical or similar components have identical reference numerals, and reference is made to the description of the first embodiment shown in FIGS. 2a and 2b.

[0114] FIG. 3 shows the vehicle 1000 in the first operating mode B1. The compressed air supply system 1200 preferably comprises a water separator 6 arranged in the pneumatic main line 12 between the compressed air connection 1 and the air dryer 5. The water separator 6 comprises a condensation dryer 16 and a separation element 26 for separating condensate K from the compressed air 110 provided at the compressed air connection 1. The water separator 6 is preferably arranged in a front region 1400 of the vehicle 1000 so that airflow supports the cooling of the compressed air 110 provided at the compressed air connection 1 to condense the moisture. More preferably, the water separator 6 further comprises a ventilation device 36 which is designed to additionally cool the compressed air provided at the compressed air connection 1 in order to improve the degree of condensation and to remove an increased amount of condensate K from the compressed air 110 provided.

[0115] Furthermore, in the exemplary embodiment shown, the branch line 14.1 is a first branch line, in which a first branch line switching valve 24.1 is preferably arranged. The compressed air supply system 100 further comprises a second branch line 14.2 extending from the pneumatic main line 12 between the compressed air connection 1 and the main line switching valve 25, which branch line preferably has a second branch line switching valve 24.2. Furthermore, the air dryer 5.1 in the pneumatic main line 12 is preferably a first air dryer 5.1, and a second air dryer 5.2 is arranged in the second branch line 14.2. The second branch line switching valve 24.2 is preferably connected to the control device 1300 via a ninth signal line S9. Further preferably, the vent line 13.1 is a first vent line and from the second branch line 14.2 goes between the second branch line switching valve 24.2 and the second air dryer 5.2 preferably terminates in a second vent line 13.2 with a second vent valve 23.3. The second vent valve 23.3 is preferably connected to the control device 1300 via a tenth signal line S10.

[0116] In the first operating mode B1 shown, neither the first air dryer 5.1 nor the second air dryer 5.2 is used to dry the compressed air 110 provided at the compressed air connection 1. Instead, the main line switching valve 25 blocks the pneumatic main line 12 in the filling direction B, and the second branch line switching valve 24.2 blocks the second branch line 14.2 in the filling direction B. If a first branch line switching valve is arranged in the first branch line 14.1, this is controlled by the control device in the first operating state B1 to release the first branch line 14.1. Compressed air 141 is thus guided in the filling direction B via the first branch line 14.1 to the compressed air supply connection 2 in the event that the freezing risk Ri determined by the control device 1300 is below the predefined limit value W (see FIG.7-9) and freezing of the residual moisture of the compressed air provided at the compressed air supply connection 2 can be ruled out with a high degree of probability.

[0117] The second embodiment of the vehicle 1000 shown in FIG. 3 differs from the first embodiment in that the compressed air supply 200 comprises a first compressor 201.1 with a first electric motor 203.1, and an additional compressed air source 50 is provided, which comprises a second compressor 201.2 with a second electric motor 203.2. The compressed air supply system 1200 preferably further comprises a temperature sensor 60, which is connected to the control device 1300 in a signal-conducting manner, for monitoring the temperature TD of the compressed air supply 200. The control device 1300 is designed to switch on the second compressed air source 50 as needed, and preferably to switch off the compressed air supply 200, depending on the monitored temperature of the compressed air supply 200. In this way, an impending overheating of the compressed air supply 200 can be detected early, and operation can be maintained.Furthermore, the control device 1300 is designed to switch on the second compressed air source 50 as needed, depending on the supply requirement Bv of the compressed air consumer 300.

[0118] Preferably, in FIG. 3, a first shut-off valve 32 can be arranged downstream of the first air dryer 5.1 in the filling direction, and a second shut-off valve 34 can be arranged downstream of the second air dryer 5.2 in the filling direction B. The shut-off valves 32, 34 can be used to pneumatically decouple the air dryers 5.1, 5.2 from the branch line 14.1, so that the saturation of the air dryers does not progress any further. FIG. 4 shows a third embodiment of the vehicle 1000. To avoid repetition, reference is made to the description of the vehicle 1000 according to the first embodiment in FIGS. 2a and 2b, and only differences are discussed. Identical or similar components have identical reference numerals here.

[0119] The third embodiment of the vehicle 1000 shown differs from the first embodiment in that the throttle 8 is now arranged in the branch line 14 upstream of the branch line switching valve 24 instead of in the pneumatic main line 12. The throttle 8 expands the compressed air 141 provided at the compressed air connection 1 at the beginning of the branch line 14, whereby the compressed air 141' is drier due to the lower air pressure. Thus, the branch line 14 and the branch line switching valve 24 arranged therein are protected from frost damage. At the same time, the throttle 8 achieves the expansion necessary for the regeneration of the air dryer 5 when the compressed air 141 is returned through the pneumatic main line 12 against the filling direction B.

[0120] Furthermore, a main line switching valve 25 is arranged in the pneumatic main line 12.

[0121] The vent valve arrangement 23 has a control valve 23.5 in the form of a 3 / 2-way solenoid valve. Furthermore, the vent valve 23.1 is designed as a pneumatically actuated vent valve 23.1. The control valve 23.5 can be controlled via electrical control signals in the form of a voltage and / or current signal. When controlled by the control device 1300 via an eleventh signal line S11, the control valve 23.5 can be moved from a normally closed position to a pneumatically open position (not shown), in which a pressure derived from the pneumatic branch line 14 via a pneumatic control line 23.5A is passed on for the pneumatic control of the controllable vent valve 23.1 by means of a bypass 23.5B. When closed, the control valve 23.5 separates the control line 23.5A and is pneumatically connected to the vent port 3 via another pneumatic line 23.5C.

[0122] The vent line 13.1 is a first vent line 13.1 in this case, and the compressed air supply system 100 further comprises a compressor vent line 13.3. The compressor vent line 13.3 branches off from the pneumatic main line 12 upstream of the main line switching valve 25 in the filling direction B. The vent valve arrangement 23 has a compressor vent valve 23.4 in the compressor vent line 13.3. Through the compressor vent line 13.3, a line volume VL between the compressed air source 200, preferably a compressor 202 in this case, and the branch line switching valve 24 and the main line switching valve 25 can be vented. The starting resistance for the compressor 202 is thus reduced.

[0123] The control valve 23.5, the compressor vent valve 23.4 as well as the branch line switching valve 24 and the main line switching valve 25 are designed as solenoid valves, in particular normally closed solenoid valves.

[0124] Preferably, the compressed air supply system 1200 in the embodiments according to FIGS. 2a, 2b, 3 and 4 further comprises a temperature sensor 60 for monitoring the temperature of the compressed air generator 200, wherein the temperature sensor 60 is connected to the control device 1300 in a signal-conducting manner and is designed to provide sensor signals S.

[0125] The compressed air consumer 300, which in this case is a sensor cleaning device 301, further comprises a first nozzle valve 302 and a second nozzle valve 303. The nozzle valves 302, 303 are also designed as solenoid valves, in particular as normally closed solenoid directional control valves. Such a solenoid directional control valve is shown as an example in Fig. 5 using a possible embodiment of a nozzle valve 302. The nozzle valve 302 is a normally closed 2 / 2-way valve 304. The nozzle valve 302 comprises a solenoid part 305 and a pneumatic part 306. The solenoid part 305 has an electrical coil 307, an armature 308.1 that can be actuated magnetically and under the influence of a spring force, and a stationary magnetizable core 308.2. An air gap 309 is formed between the armature 308.1 and the core 308.2, which defines the possible stroke of the armature 308.1.

[0126] The pneumatic part 306 comprises a first compressed air passage 310 and a second compressed air passage 311. The pneumatic part 306 further comprises a valve stem part 312, which has an abutment surface 313 pointing toward the armature 308.1.

[0127] The nozzle valve 302 further comprises a valve spring 314, which is configured to apply a spring force FF to the armature 308.1 in the direction of the valve stem part 312, in particular the abutment surface 313. In the open state of the nozzle valve 302, the armature 308.1 is spaced from a valve seat 315 of the pneumatic part 306.

[0128] The armature 308.1 is movably received in the magnetic part 305 and the pneumatic part 306. By energizing the electrical coil 307, it generates a magnetic field with a magnetic force FM. The resulting magnetic field creates a magnetic pole on the core 308.2, which attracts the armature 308.1 and moves it away from the valve seat 315 against the spring force FF of the valve spring 314, so that the first compressed air passage 310 and the second compressed air passage 311 are fluidly connected. The magnitude of the magnetic force FM depends on the applied control current Si, which is provided by the control device 1300. The opening control current Sn required to open the nozzle valve 302 is greater than the holding control current S12 required to hold the nozzle valve 302 in the open position. The magnitude of the force exerted by a magnetic field induced by the coil 307 on the armature 308.1 at a constant current depends on the distance of the armature 308.1 relative to the magnetic field, i.e. the size of the air gap 309 between armature 308.1 and core 308.2. At a greater distance, a weaker magnetic field acts. In the closed position, armature 308.1 is initially at a greater distance from the magnetic field, so that an increased current, namely an opening control current Sn, is provided. The opening control current Sn required to open nozzle valve 302 refers to the current required to reduce the distance between armature 308.1 and core 308.2 and thus the air gap 309. As soon as armature 308.1 moves into an open position, its distance from the magnetic field is reduced and a lower holding control current S12 is sufficient to hold armature 308.1 in this position. Preferably, the control device 1300 is further configured to apply a heating control current S13 to the nozzle valve 302, which is smaller than the opening control current S11, in particular also smaller than the holding control current.

[0129] 512, such that the nozzle valve 302 is heated by the generated magnetic field in the closed state.

[0130] The control device 1300 shown in FIGS. 2a to 4 is designed to provide a control current Si equal to the opening control current S11 (see FIG. 5) for opening the compressor vent valve 23.4 as well as the branch line switching valve 24, the main line switching valve 25, and the nozzle valves 302, 303. Furthermore, the control device 1300 is also designed to supply one, several, or all of these valves with a heating control current.

[0131] 513 to be applied.

[0132] FIGS. 6a to 6d show a section of the compressed air supply system 1200 according to FIGS. 2a, 2b, with various embodiments of the pneumatic arrangement 20 shown in detail. To avoid repetition and to explain the operation of the pneumatic arrangement 20, reference is therefore made to the description of FIGS. 2a, 2b.

[0133] The pneumatic arrangement 20 according to FIG. 6a comprises a controllable throttle valve 21, which is designed to throttle compressed air guided to the compressed air supply connection 2 in the filling direction B. The throttle valve 21 has a variable flow cross-section Q and is connected for control purposes, i.e., in a signal-conducting manner, to the control device 1300. The control device 1300 is designed to control the throttle valve 21 to change the flow cross-section Q in order to throttle the pressure in the pneumatic main line 12 to a supply pressure to be provided, in particular 5 bar. The throttle valve 21 has a throttle point 21A with a variable flow cross-section Q, wherein the throttle valve 21 has a control pressure line 21B for carrying a control pressure Ps and is designed to regulate the flow cross-section Q depending on the control pressure Ps.

[0134] The pneumatic arrangement 20 according to FIG. 6b comprises a controllable throttle valve 21, analogous to the embodiment shown in FIG. 6a. Furthermore, the compressed air supply system 1200 comprises an additional compressed air source 50 in addition to the compressed air generator 200, which in FIG. 3 comprises a compressor 201 and an electric motor 203. The compressed air source 50 comprises a reservoir 51 for storing compressed air, wherein the reservoir 51 is connected to the pneumatic main line 12 via a reservoir switching valve 52. The compressed air source 50 is designed to be connected to the pneumatic main line 12 as needed by controlling the reservoir switching valve 52. The control device 1300 (cf. FIG. 2a or 2b) is connected to a reservoir pressure sensor 53 in a signal-conducting manner and is designed to control the reservoir switching valve 52.By controlling the reservoir switching valve 52, a defined amount of compressed air can be fed into the pneumatic main line 12, wherein the control device 1300 regulates the pressure quantity via the signals of the reservoir pressure sensor 53 and / or via the reservoir switching valve 52.

[0135] The pneumatic arrangement 20 according to FIG. 6c comprises a pair of counter-opening and fluidically parallel check valves 27, 28, which are arranged between the air dryer 5 and the compressed air supply connection 2. The pair of check valves 27, 28 comprises a first check valve 27 opening in the filling direction B, which is arranged in the pneumatic main line 12, and a second check valve 28 opening in the return direction R. The second check valve 28 is arranged in a bypass line 15, which forms a bypass around the first check valve 27. The pneumatic arrangement 20 further comprises a return throttle valve 29 arranged downstream of the second check valve 28 in the return direction R.

[0136] The pneumatic arrangement 20 according to FIG. 6d is designed for use with compressed air supply systems as shown in FIG. 3, i.e., for compressed air supply systems with two air dryers 5.1, 5.2. A first pair of counter-opening and fluidically parallel check valves

[0137] 27.1. 28.1 with a corresponding return throttle valve 29.1, as described with reference to the embodiment according to FIG. 6c, is assigned to the first air dryer 5.1 and is arranged between the first air dryer

[0138] 5.1 and the compressed air connection 2.

[0139] A second pair of counter-opening and fluidically parallel check valves 27.2, 28.2 with a corresponding second return throttle valve 29.2, as described with reference to the embodiment according to FIG. 6c, is assigned to the second air dryer 5.2 and arranged between the second air dryer 5.2 and the compressed air connection 2.

[0140] FIG. 7 schematically shows the sequence of a control method 2000. The control method 2000 comprises, in a first step 2100, the receipt of a supply requirement Bv of the compressed air consumer 300 by the control device 1300. Receiving the supply requirement in step 2100 preferably comprises the determination or receipt of a supply pressure Vp and / or a supply volume flow Vv depending on the supply requirement Bv of the compressed air to be provided at the compressed air connection 2 by the control device 1300 in step 2110. In a second step 2200, the method comprises the control device 1300 controlling the compressed air generator 200 to provide compressed air at the compressed air supply connection 1 in the event that the control device 1300 receives a supply requirement Bv.

[0141] Preferably, the second step further comprises a regulation 2210 of the supply pressure Vp and / or the supply volume flow Vv of the compressed air 120', 141' to be provided at the compressed air supply connection 2 by the control device 1300 depending on the supply requirement Bv.

[0142] The control device 1300 is signal-conductingly connected to at least one pressure sensor 9 arranged in the pneumatic main line 12 for providing sensor signals S relating to an input pressure P, and to a pressure regulator 40 assigned to the pneumatic main line 12 and / or the compressed air connection 1. Regulating the supply pressure 2210 preferably comprises controlling 2212 the pressure regulator 40 or the pneumatic arrangement 20 by the control device 1300 depending on the sensor signals S. Additionally or alternatively, the control device 1300 is signal-conductingly connected to the electric motor 203, in particular the BLDC electric motor 204, and regulating the supply pressure 2210 comprises regulating 2214 a motor speed M of the electric motor 203 by the control device 1300.

[0143] Furthermore, the activation of the compressor 201 in step 2200 preferably also includes the activation of an additional compressed air source 50, as shown in FIGS. 3 and 6b, as needed. In this case, the activation of an additional compressed air source 50 is understood to mean connecting the compressed air source 50 to the main pneumatic line 12. An additional compressed air source 50, which may be an additional compressor 201.2 and / or a reservoir 51, increases the available compressed air quantity, i.e., the available volume flow, and allows for response to varying system requirements. In step 2220, the control device 1300 controls the compressed air source 50 depending on the supply requirement Bv of the compressed air consumer 300 and / or a sensor information S detected by the temperature sensor 60, namely a temperature TD of the compressed air generator 200 or a saturation level G of one of the air dryers 5, 5 monitored by the control device 1300.1 , 5.2.

[0144] Furthermore, in a third step 2300, the method 2000 comprises determining a freezing risk Ri. The environmental information lu preferably comprises a current temperature T, a current air humidity H of the environment A, a climate zone, an average temperature TA, and an average air humidity HA of the environment A. It should be understood that the environmental information lu can comprise one, several, or all of these. The environmental information lu is determined at a current location Pi and / or along a route P and / or at a destination P3. The method 2000 therefore comprises determining the environmental information lu in a step 2310 and retrieving the environmental information lu in step 2320 by the control device 1300.

[0145] Furthermore, the method according to FIG. 7 includes, in the event that the freezing risk Ri determined in step 2300 is below a predefined limit value W, the actuation of the main line switching valve 25 (see FIGS. 2a-3) to block the pneumatic main line 12 in step 2400, and in step 2500, the routing of compressed air from the compressed air connection 1 to the compressed air supply connection 2 via the branch line 14, 14.1 (see FIGS. 2a-5). If present, the branch line switching valve 24 is additionally actuated in step 2400.

[0146] The method further comprises controlling 2510 the pneumatic arrangement 20 and, in this case, preferably controlling 2512 a throttle valve 21 according to FIG. 6a or 6b for regulating the supply pressure Vp at the compressed air supply connection 2.

[0147] In the event that the determined freezing risk Ri reaches or exceeds a predefined limit value W, the main line switching valve 25 is controlled in step 3400 in the second operating mode B2 to open the pneumatic main line 12, allowing pneumatic flow. Compressed air is then supplied from the compressed air connection 1 via the pneumatic main line 12 to the compressed air supply connection 2 in step 3500.

[0148] The method further comprises controlling 3510 the pneumatic arrangement 20 for distributing the compressed air 141 guided in the branch line 14, 14.1, 14.2, for example depending on the supply requirement Bv, to the pneumatic main line 12 for return against the filling direction B and to the compressed air supply connection 2. The controlling 3510 of the pneumatic arrangement 20 preferably comprises controlling 3512 a throttle valve 21 according to FIG. 6a or 6b for regulating the supply pressure Vp at the compressed air supply connection 2 or controlling 3514 a return throttle valve 29, 29.1, 29.2 for regulating the pressure of the compressed air returned against the filling direction B.

[0149] Following the routing of compressed air through the branch line in step 2500 or the routing of compressed air through the pneumatic main line in step 3500, the pneumatic main line 12 and / or the branch line 14, 14.1 and / or the nozzle valves 302, 303 can preferably be flushed with compressed air 120' provided at the compressed air connection 1 and dried by the air dryer 5, and the compressed air can be discharged via the vent line 13 in step 2600. Thus, the pneumatic main line 12 and the branch line 14, 14.1 are freed of residues and residual moisture. Subsequently, the method 2000 preferably comprises controlling the main line switching valve 25 and the branch line switching valve 24, 24.1 to pneumatically decouple the pneumatic main line 12 and the branch line from the compressed air connection.By depressurizing the compressed air supply system 100 in this way, i.e., placing the compressed air supply system 100 into a standby mode, the pneumatic main line 12 or the branch line 14, 14.1, 14.2 is protected from frost damage. Preferably, the flushing in a sub-step 2610 further comprises actuating the compressor vent valve 23.4 to vent a line volume between the compressed air transmitter 200 and the branch line switching valve 24, 24.1, 24.2 and the main line switching valve 25. Alternatively or additionally, the venting can also take place before actuating the compressed air transmitter 200 in step 2200.

[0150] FIG. 8 shows a second embodiment of the method 4000 according to the invention.

[0151] In the method according to FIG. 8, the retrieval or determination in step 2310 also includes retrieving location information IGPS in step 2312 relating to the route P and / or the destination P3. The retrieval of the location information IGPS preferably occurs from an on-board network 1600 connected via a data interface 70 and / or a navigation system 1700 (see FIG. 1). Likewise, the retrieval of the environmental information lu in step 2320 can include retrieving current location information IGPS in step 2322. It is further preferred that the retrieved temperature T and / or air humidity H as environmental information lu relate to a current temperature T or air humidity H of the environment A, which is retrieved in a step 2324 by the control device 1300 from at least one signal-conductingly connected ambient temperature sensor 410 and / or air humidity sensor 400 (see FIG. 1) or from a signal-conductingly connected on-board network 1700 (see FIG. 1).

[0152] The method 4000 further differs from the method 2000 shown above in FIG. 7 in that the control device 1300, in a step 2800, further determines a saturation level G of the first air dryer 5.1 and preferably of the second air dryer 5.2 depending on the ambient information Iu and / or the operating state information IB. Furthermore, the freezing risk Ri is determined in a known manner depending on this information. Furthermore, determining the freezing risk can, in a known manner, comprise retrieving location information IGPS relating to the route P and / or the destination P3. The operating state information IB comprises the operating time tß and the temperature TD of the compressed air generator 200. Depending on the determined saturation level G, in particular of the first air dryer 5.1 and the freezing risk Ri, the control device 1300 is designed, in the event that the freezing risk Ri is below a predefined limit value W, to control the main line switching valve 25 in a known manner to block the pneumatic main line 12, wherein the pressure supply system 1200 is operated in the first operating mode B1. Furthermore, the control device 1300 is designed, in step 2410, to further control the first branch line switching valve 24.1 to release the first branch line 14.1 and, in step 2420, to further control the second branch line switching valve 24.2, preferably to block the second branch line 14.2. Compressed air is then conducted from the compressed air connection 1 to the compressed air supply connection 2 via the first branch line in step 2500.

[0153] In the event that the freezing risk Ri reaches or exceeds the predefined limit value W and the saturation level G is below a maximum saturation level Gmax, the control device 1300 controls the main line switching valve 25 to release the pneumatic main line 12 in step 3400. More preferably, in this case, the control device 1300 further controls the first branch line switching valve 24.1 in step 3410 to block the first branch line 14.1 and the second branch line switching valve 24.2 in step 3420 to block the second branch line 14.2. Subsequently, in the second operating mode B2, compressed air is conducted via the pneumatic main line 12 from the compressed air connection 1 to the compressed air supply connection 2, wherein the compressed air is dried by the first air dryer 5.1.

[0154] Preferably, in the first operating mode, the method 4000 further comprises controlling a first shut-off valve 32 (see FIG. 3) arranged downstream of the first air dryer in the filling direction to block the pneumatic main line 12 in the first operating mode B1 in the event that the freezing risk Ri is below the predefined limit value W in step 2900. Further preferably, the method 4000 in the first operating mode B1 comprises controlling the second shut-off valve 34 (see FIG. 3) arranged downstream of the second air dryer 5.2 in the filling direction to block the second branch line 14.2 in the event that the freezing risk Ri is below the predefined limit value W (step 2910). Thus, in the first operating mode, the first air dryer 5.1 and the second air dryer 5.2 are also pneumatically decoupled from the first branch line 14.1 in a direction opposite to the filling direction B, so that the saturation of the respective air dryer 5.1, 5.2 is not pursued further.

[0155] The control device 1300 is further configured to actuate the main line switching valve 25 in step 4400 to block the pneumatic main line 12 in the event that the freezing risk Ri reaches or exceeds the predefined limit value W and the saturation level G of the first air dryer 5.1 exceeds a permissible maximum saturation level Gmax. Furthermore, in this case, the control device 1300 is designed to block the first branch line switching valve 24.1 to block the first branch line 14.1 (step 4410) and preferably to control the second branch line switching valve 24.2 to release the second branch line 14.2 in step 4420. By corresponding control, compressed air can then be guided from the compressed air connection 1 to the compressed air supply connection 2 via the second branch line 14.2 in the filling direction B in step 4500 and from the second air dryer 5.2, wherein the compressed air supply system 1200 is operated in the third operating mode B3.

[0156] FIG. 9 shows a third embodiment of the method 5000 according to the invention for controlling a compressed air supply system 1200, as shown in FIG. 4. The main line switching valve 25, the branch line switching valve 24, or optionally also two branch line switching valves, as shown in FIG. 1 and FIG. 3, the compressor vent valve 23.4, and preferably also the first vent valve 23.1 are designed as normally closed 2 / 2-way solenoid valves. Identical or similar method steps have identical reference numerals here, and reference is made to the description of the method shown in FIG. 7, with only differences being discussed. The method 5000 comprises the first step 2100 to the ninth step 2900 of the method 4000 according to FIG. 8.

[0157] According to method 5000, the actuation 2610 of the compressor vent valve 23.4 to release the compressor vent line 13.2 further includes energizing 2612 the compressor vent valve 23.4 with a heating current Si3. Thus, the compressor vent valve 23.4 can first be heated before it is energized with an opening current Sn to release the compressor vent line 13.2 in step 2200. It is also possible to continuously energize the valves with the heating current Si3 during operation, thus heating them.

[0158] Furthermore, the actuation of the main line switching valve 25 in the second operating mode B2 in step 3400 further includes energizing 3401 the main line switching valve 25 with a heating current Si3. Thus, the main line switching valve 25 can first be heated before it is energized with an opening current Sn in step 3400 to release the pneumatic main line 12.

[0159] Furthermore, the actuation of the first branch line switching valve 24.1 (see FIG. 3) or the branch line switching valve 24.1 (see FIG. 4) in the first operating mode B1 in step 2410 for releasing the (first) branch line 14,

[0160] 14.1 furthermore the energization 2411 of the (first) branch line switching valve 24,

[0161] 24.1 with a heating current Si3. Thus, the (first) branch line switching valve 24, 24.1 can first be heated before it is energized with an opening current Sn in step 2410 to release the (first) branch line 14, 14.1.

[0162] Furthermore, the actuation 4420 of a second branch line switching valve 24.2 in the third operating mode B3 in step 4420 further comprises energizing the second branch line switching valve 24.2 with a heating current Si3 in step 4421. Thus, the second branch line switching valve 24.2 can first be heated before it is energized with an opening current S11 in step 4420 to release the second branch line 14.2.

[0163] In a corresponding manner, the vent valve 23.1 can also first be supplied with a heating current Si3 before applying an opening current Sn.

[0164] Thus, all solenoid valves can be heated before they are energized with an opening current Sn to release the respective flow path.

[0165] When determining the freezing risk Ri depending on the ambient information lu and / or the operating state information IB of the compressed air transmitter 200 in step 2300, the control device 1300 determines a reduced freezing risk R12 in step 2326, since the control device 1300 is designed to apply a heating control current Si3 and the solenoid valves 23.1, 23.4, 24, 24.1, 24.2, 25 and the nozzle valves 302, 303 are thus protected from frost damage even at temperatures close to freezing point.

[0166] In the context of the invention, it should be understood that the first operating mode B1 denotes a bypass mode in which non-dried compressed air or compressed air only partially dehumidified by the water separator 6 is conveyed to the compressed air supply connection 2. The second operating mode B2 relates to a basic operating mode in which compressed air dried by the (first) air dryer 5, 5.1 is conveyed to the compressed air supply connection 2. The third operating mode B3 relates to an alternative drying operating mode in which compressed air for the compressed air consumer 300 and / or for the regeneration of the first air dryer 5.1 is conveyed through the second air dryer 5.2. Reference numerals (part of the description)

[0167] 1 compressed air connection

[0168] 2 compressed air supply connection

[0169] 3 vent connection

[0170] 5 air dryers

[0171] 5.1 first air dryer

[0172] 5.2 second air dryer

[0173] 6 water separators

[0174] 8 Throttle

[0175] 8.1 first throttle

[0176] 8.2 second throttle

[0177] 9 Pressure sensor

[0178] 12 pneumatic main line

[0179] 13 Ventilation line

[0180] 13.1 first vent line

[0181] 13.2 second vent line

[0182] 13.3 Compressor vent line

[0183] 14 Branch Management

[0184] 14.1 first branch line

[0185] 14.2 second branch line

[0186] 15 Bypass line

[0187] 16 condensation dryers

[0188] 20 Pneumatic arrangement

[0189] 21 Throttle valve in pneumatic main line

[0190] 21A throttle point

[0191] 21 B Control pressure line

[0192] 23 Vent valve arrangement

[0193] 23.1 first vent valve

[0194] 23.2 Vent check valve

[0195] 23.3 second vent valve

[0196] 23.4 Compressor vent valve

[0197] 23.5 Control valve .5A Control line .5B Bypass .5C Line

[0198] Switching valve .1 first branch line switching valve .2 second branch line switching valve pneumatic switching valve

[0199] Separator , 27.1 , 27.2 first check valve , 28.1 , 28.2 second check valve , 29.1 , 29.2 return throttle valve first check valve second check valve

[0200] ventilation unit

[0201] pressure regulator

[0202] Compressed air source

[0203] reservoir

[0204] Reservoir switching valve

[0205] Reservoir pressure sensor

[0206] Temperature sensor

[0207] Data interface

[0208] Data bus

[0209] CAN bus 0 Compressed air supply system 1 Pressure control module 0 Compressed air at the compressed air connection 0 Partially dehumidified compressed air in the pneumatic main line 0' Dried compressed air in the pneumatic main line 1 Moist compressed air in the vent line 1 Compressed air in / from the first branch line 1 ' Relaxed compressed air from the first branch line 0 Compressed air sensor 1 Compressor 203 Electric motor

[0210] 204 BLDC electric motor

[0211] 300 compressed air consumers

[0212] 301 Sensor cleaning device

[0213] 302 first nozzle valve

[0214] 303 second nozzle valves

[0215] 304 2 / 2-way valve

[0216] 305 magnetic part

[0217] 306 Pneumatic part

[0218] 307 coil

[0219] 308 anchors

[0220] 309 Air gap

[0221] 310 first compressed air passage

[0222] 311 second compressed air passage

[0223] 312 valve stem part

[0224] 313 impact surface

[0225] 314 valve spring

[0226] 315 valve seat

[0227] 400 Humidity Sensor

[0228] 410 Ambient temperature sensor

[0229] 1000 vehicles

[0230] 1100 passenger cars

[0231] 1200 compressed air supply system

[0232] 1300 control unit

[0233] 1310 computing device

[0234] 1320 processor

[0235] 1400 front area of ​​the vehicle

[0236] 1600 on-board network

[0237] 1610 On-board network memory

[0238] 1620 On-board network battery

[0239] 1700 navigation system

[0240] 2000, 4000, 5000 procedures

[0241] 2100 Receiving a supply demand 2110 Receiving or determining a supply pressure and / or a supply volume flow

[0242] 2200 Control of a compressed air sensor

[0243] 2210 Control of supply pressure and / or volume flow

[0244] 2220 Control of an additional compressed air source

[0245] 2300 Determining a freezing risk

[0246] 2310 Determining the environmental information

[0247] 2320 Retrieving environmental information

[0248] 2312, 2322 Retrieving location information and surrounding information

[0249] 2324 Retrieve the current temperature and / or humidity

[0250] 2326 Determining a reduced risk of freezing

[0251] 2400 Control of a main line switching valve in the first operating mode

[0252] 2410 Control of a first branch line switching valve in the first operating mode

[0253] 2411 Energize the (first) branch line switching valve with a heating current

[0254] 2420 Control of a second branch line switching valve in the first operating mode

[0255] 2500 Supplying compressed air through the (first) branch line

[0256] 2510 Control of the pneumatic arrangement

[0257] 2512 Control of the throttle valve

[0258] 2600 Flushing the pneumatic main line

[0259] 2610 Control the compressor vent valve for venting

[0260] 2612 Energize the compressor vent valve with a

[0261] Heating electricity

[0262] 2700 pneumatic decoupling

[0263] 2800 Determining a saturation level

[0264] 2900 Control of a first shut-off valve

[0265] 2910 Control of a second shut-off valve

[0266] 2101 Prefilling the pneumatic main line

[0267] 2102 Release of the pre-filled pneumatic main line 3400 Control of the main line switching valve in the second operating mode

[0268] 3401 Energize the main line switching valve with a heating

[0269] Electricity

[0270] 3410 Control of a first branch line switching valve in the second operating mode

[0271] 3420 Control of a second branch line switching valve in the second operating mode

[0272] 3500 Supplying compressed air through the pneumatic main line

[0273] 3512 Control of the throttle valve

[0274] 4400 Control of a second branch line switching valve in the third operating mode

[0275] 4410 Control of a first branch line switching valve in the third operating mode

[0276] 4420 Control of a main line switching valve in the third operating mode

[0277] 4421 Energize the second branch line switching valve with a heating current

[0278] 4500 Supplying compressed air through the (second) branch line

[0279] S1 first signal line

[0280] S2 second signal line

[0281] S3 third signal line

[0282] S4 fourth signal line

[0283] S5 fifth signal line

[0284] S6 sixth signal line

[0285] S6.1 CAN bus connection

[0286] S7 seventh signal line

[0287] S8 eighth signal line

[0288] S9 ninth signal line

[0289] S10 tenth signal line

[0290] F Direction of travel

[0291] B Filling direction

[0292] R Return direction E Vent direction

[0293] B1 first operating mode

[0294] B2 second operating mode

[0295] B3 third operating mode

[0296] K Condensate

[0297] P Inlet pressure, sensor information

[0298] PV supply pressure

[0299] Vv supply volume flow

[0300] Bv supply needs

[0301] H Humidity, sensor information

[0302] T Temperature, sensor information

[0303] HA average humidity

[0304] TA average temperature

[0305] TD Temperature of the compressed air sensor

[0306] S sensor signal

[0307] G Saturation level

[0308] GMSX maximum saturation level

[0309] M Engine speed

[0310] IGPS location information lu environmental information tß operating time

[0311] I Current

[0312] W limit

[0313] VL line volume

[0314] FF spring force

[0315] FM magnetic force

[0316] Si control current

[0317] Sn opening control current

[0318] 512 Holding control current

[0319] 513 Heating control current

[0320] Ps control pressure

[0321] Q flow cross-section

[0322] Ri freezing risk Rr reduced freezing risk

[0323] Pi current location

[0324] P Route

[0325] P3 Destination

Claims

Patent claims 1. Method (2000, 4000, 5000) for controlling a compressed air supply system (1200) for a vehicle (1000), in particular a passenger car (1100), wherein a control device (1300) is assigned to the compressed air supply system for supplying a compressed air consumer via a compressed air supply connection (2), and the compressed air supply system (1200) comprises a compressed air generator (200) for providing compressed air (110) at a compressed air connection (1), a pneumatic main line (12) with an air dryer (5, 5.1) for drying and guiding compressed air (110, 120, 120') to the compressed air supply connection (2) in a filling direction (B), and a pneumatic main line (12) leading from the pneumatic main line (12) in the filling direction (B) upstream of the air dryer (5, 5.1) and downstream of the air dryer (5, 5.1 , 5.2) has a branch line (14, 14.1 , 14.2) connecting to the branch line (14, 14.1 , 14.2), and the method (2000, 4000, 5000) comprises the steps: Receiving (2100) a supply requirement (Bv) of the compressed air consumer (300) by the control device (1300), Controlling (2200) the compressed air generator (200), in particular an electric motor (203) associated with the compressed air generator (200), by the control device (1300) to provide compressed air (110) at the compressed air connection (1 ), in the event that the control device (1300) receives a supply requirement (Bv), Determining (2300) a freezing risk (Ri) by the control device (1300) depending on environmental information (lu) and / or operating state information (IB) of the compressed air generator (200), Controlling (2400) a main line switching valve (25) by the control device (1300) to block the pneumatic main line (12) in a first operating mode (B1) in the event that the freezing risk (Ri) is below a predefined limit value (W), Leading (2500) compressed air (141) through the branch line (14, 14.1, 14.2) to the compressed air supply connection (2) in the filling direction (B) in the first operating mode (B1) to supply the compressed air consumer (300).

2. Control method (2000, 4000, 5000) according to claim 1, further comprising the steps of: Controlling (3400) the main line switching valve (25) by the control device (1300) to release the pneumatic main line (12) in a second operating mode (B2) in the event that the freezing risk (Ri) reaches or exceeds the limit value (W), Leading (3500) through the pneumatic main line (12) to the compressed air supply connection in a filling direction (B) depending on the supply requirement (Bv) and drying compressed air (120) by the air dryer (5, 5.1) in the second operating mode (B2).

3. Control method (2000, 4000, 5000) according to claim 1 or 2, wherein determining (2300) the freezing risk (Ri) further comprises determining (2310) and / or retrieving (2320) the environmental information (lu) by the control device (1300).

4. Control method (2000, 4000, 5000) according to claim 3, wherein the environmental information (lu) comprises one, several or all of the following: a current temperature (T) of the environment (A), a current humidity (H) of an environment (A), a climate zone, an average temperature (TA) of the environment (A), an average humidity (HA) of the environment (A).

5. Control method (2000, 4000, 5000) according to one of claims 2 to 4, wherein the environmental information (lu) is determined at a current location (Pi) and / or along a route (P) and / or at a destination (P3), and determining (2310) the environmental information (lu) comprises retrieving (2312) location information (IGPS) relating to the route (P) and / or the (P3) destination from an on-board network (1600) connected via a data interface (70) and / or a navigation system (1700), and / or the retrieval (2320) of the environmental information (lu) comprises the retrieval (2322) of location information (IGPS) relating to the route (P) and / or the destination (P3) from an on-board network (1600) connected via a data interface (70) and / or a navigation system (1700).

6. Control method (2000, 4000, 5000) according to one of claims 4 or 5, wherein the temperature (T) and / or the air humidity (H) comprise a current temperature (T) and / or air humidity (H) of the environment (A), and the retrieval (2320) of the environmental information (lu) comprises the retrieval (2324) of the current temperature (T) and / or air humidity (H) by the control device (1300) from at least one signal-conductingly connected ambient temperature sensor (410) and / or air humidity sensor (400) or from a signal-conductingly connected on-board network (1600).

7. Control method (2000, 4000, 5000) according to claim 6, wherein the freezing risk (Ri) is below the predefined limit value (W) in the event that the environmental information (lu) satisfies at least one of the following conditions: the air humidity is at most 1 g / m 3, the ambient temperature is at least 15°C, in particular at least 20°C, the average temperature is at least 20°C, the average humidity is at most 0.5 g / m 3 , in particular not more than 0.25 g / m 3 , the climate zone is tropical or subtropical.

8. Control method (2000, 4000, 5000) according to one of the preceding claims, wherein the operating state information (IB) comprises one, several or all of the following: an operating time (tß) of the compressed air generator (200), in particular of the electric motor (203), which is transmitted via a signal-conducting connection (S6), in particular re via a CAN bus connection (S6.1), monitored by the control device (1300), a temperature of the compressed air generator (200), in particular of the electric motor (203, 203.1, 203.2), which is measured directly or indirectly by at least one temperature sensor (60) and monitored by the control device (1300).

9. Control method (2000, 4000, 5000) according to claim 8, wherein the freezing risk (Ri) is below the predefined limit value (W) in the event that at least the operating state information (IB) fulfills at least one of the following conditions: the operating time (tß) of the compressed air generator (200) within 15 minutes is at least 5 minutes, the temperature (TD) of the compressed air generator (200) is at least 60 °C 10. Control method (2000, 4000, 5000) according to one of the preceding claims 2 to 9, wherein the method further comprises controlling (3410) a branch line switching valve for blocking the branch line in the filling direction (B) in the second operating mode (B2) in the event that the freezing risk (Ri) exceeds the predefined limit value.

11. The control method (2000, 4000, 5000) according to claim 10, wherein the method further comprises at least one of the following steps: Flushing (2600) the pneumatic main line (12) against the filling direction (B) and / or the branch line (14, 14.1, 14.2) in the filling direction (B) by means of compressed air (120') provided at the compressed air connection (1) and dried by the air dryer (5) and discharging the compressed air (120') via the vent line (13), and / or Flushing the compressed air receiver (300) by means of compressed air (120') provided at the compressed air connection (1) and dried by the air dryer and discharging the compressed air (120') via the compressed air receiver (300), and / or Controlling (2700) the main line switching valve (25) and the branch line switching valve (24, 24.1, 24.2) for pneumatically decoupling the pneumatic main line (12), in particular the air dryer (5, 5.1), and the branch line (14, 14.1, 14.2), from the compressed air connection (1).

12. Control method (2000, 4000, 5000) according to one of the preceding claims, wherein the compressed air supply system (1200) has a pneumatic arrangement associated with the compressed air supply connection and connected to the control device (1300) in a signal-conducting manner, and the method (2000, 4000, 5000) further comprises at least one of the following steps: Pre-filling (2101) of the pneumatic main line (12) and / or the branch line (14, 14.1, 14.2) with compressed air (110, 120) via the compressed air connection (1), wherein the pneumatic arrangement (20) pneumatically decouples the pneumatic main line (12) and / or the branch line (14, 14.1, 14.2) and / or the compressed air supply connection (2) from the compressed air consumer (300), Controlling (2102) the pneumatic arrangement (20) to release the compressed air supply connection (2) and / or the pneumatic main line (12) after pre-filling (2101) the pneumatic main line (12).

13. Control method (2000, 4000, 5000) according to one of the preceding claims, wherein the branch line (14.1) is a first branch line (14.1) with a first branch line switching valve (24.1) and the compressed air supply system (1200) further comprises a second branch line (14.2) with a second branch line switching valve (24.2) and a second air dryer (5.2), and the method (2000, 4000, 5000) comprises: Determining (2800) a saturation level of the first air dryer (5.1) and preferably of the second air dryer (5.2) by the control device (1300) depending on the environmental information (lu) and / or the operating state information (IB), Controlling (4400) the second branch line switching valve (24.2) by the control device (1300) to release the second branch line (14.2) in a third operating mode (B3) in the event that the risk of freezing (Ri) reaches or exceeds the limit value (W) and the saturation level (G) of the first air dryer (5.1) reaches a maximum saturation level (Giviax), Leading (4500) compressed air through the second branch line (14.2) to the compressed air supply connection (2) in a filling direction (B) depending on the supply requirement (Bv) and drying compressed air by the second air dryer (5.2) in the third operating mode (B3).

14. Control method (2000, 4000, 5000) according to one of the preceding claims, wherein the method (2000, 4000, 5000) further comprises: Controlling (2900) a first shut-off valve (32) arranged downstream of the first air dryer (5, 5.1) in the filling direction (B) to shut off the pneumatic main line (12) in the first operating mode (B1) in the event that the risk of freezing (Ri) is below the predefined limit value (W), and / or Actuating (2910) a second shut-off valve (34) arranged downstream of the second air dryer (5.2) in the filling direction (B) to shut off the second branch line (14.2) in the first operating mode (B1), in the event that the risk of freezing (Ri) is below a predefined limit value (W, and / or Controlling (3420) the second branch line switching valve to block the second branch line (14.2) in the second operating mode (B2) and / or Controlling (4410) the first branch line switching valve to block the first branch line (14, 14.1) in the third operating mode (B3).

15. Control method (2000, 4000, 5000) according to one of the preceding claims, wherein the method (2000, 4000, 5000) further comprises, after receiving the supply requirement (Bv): Determining (2110) a supply pressure (Vp) and / or a supply volume flow (Vv) depending on the supply requirement (Bv) of the Compressed air supply connection (2) to be provided by the control device (1300), Regulating (2210) the supply pressure (Vp) and / or the supply volume flow (Vv) of the compressed air provided at the compressed air supply connection (2) by the control device (1300) depending on the supply requirement (Bv), wherein the control device (1300) is signal-conductingly connected to at least one pressure sensor (9) arranged in the pneumatic main line (12) for providing sensor signals (S) and to a pressure regulator (40) assigned to the pneumatic main line (12) and / or the compressed air connection (1), and regulating the supply pressure (2210) comprises controlling (2212) the pressure regulator (40) by the control device (1300) depending on the sensor signals (S), and / or the control device (1300) is signal-conductingly connected to the electric motor (203), in particular BLDC electric motor (204), wherein regulating the supply pressure (2210) comprises regulating (2214) a motor speed (M) of the electric motor (203) by the control device (1300).

16. Control method (2000, 4000, 5000) according to one of the preceding claims, wherein the control device (1300) is connected to a pneumatic arrangement (20) associated with the compressed air supply connection (2), and the method (2000, 4000, 5000) comprises: Controlling (2212) the pneumatic arrangement (20) by the control device (1300) depending on sensor signals (S) of a temperature sensor (60) associated with the compressed air generator (200) and / or the supply requirement (Bv), and / or Controlling (220) an additional compressed air source (50) depending on the supply requirement (Bv) of the air dryer (5, 5.1, 5.2) and / or a sensor signal (S) of a temperature sensor (60) assigned to the compressed air generator (200).

17. Control method (5000) according to one of the preceding claims, one, several or all of the following are designed as normally closed solenoid directional control valves: the at least one branch line switching valve (24, 24.1, 24.2), the at least one main line switching valve (25, 32, 34), at least one nozzle valve (302, 303) of a sensor cleaning device (301) connected to the compressed air supply system (100), the at least one vent valve (23.1), and a compressor vent valve (23.4), The method further comprises selectively energizing with an opening control current (Sn) and a heating control current (S13) one, several or all of the following: the at least one branch line switching valve (24, 24.1, 24.2), the at least one main line switching valve (25, 32,34), the at least one nozzle valve (302, 303) of a sensor cleaning device (301) connected to the compressed air supply system (100), the at least one vent valve (23.1), and the compressor vent valve (23.4).

18. Control method (5000) according to claim 17, wherein the control device (1300) determines (2326) a reduced freezing risk (R12) when determining (2300) the freezing risk (Ri) depending on the environmental information (lu) and / or the operating state information (IB) of the compressed air generator (200), in the event that the control device (1300) is designed to apply a heating control current (S13).

19. Control device (1300) for controlling a compressed air supply system (1200) for a vehicle (1000), in particular a passenger car (1100), wherein the control device (1300) is assigned to the compressed air supply system (1200) for supplying a compressed air consumer (300) via a compressed air supply connection (2) and the compressed air supply system (1200) comprises a compressed air generator (200) for providing compressed air (110) at a compressed air connection (1), a pneumatic main line (12) with a Air dryer (5, 5.1) for drying and guiding compressed air (110, 120, 120') to the compressed air supply connection (2) in a filling direction (B) and a branch line (14, 14.1, 14.2) leading from the pneumatic main line (12) in the filling direction (B) upstream of the air dryer (5, 5.1) and connecting again downstream of the air dryer (5, 5.1, 5.2), wherein the control device (1300) is designed to determine a freezing risk (Ri) depending on environmental information (lu) and / or operating state information (IB) of the compressed air generator (200) and to control a main line switching valve (25) for blocking the pneumatic main line (12) in a first operating mode (B1), in the event that the Freezing risk (Ri) is below a predefined limit (W).

20. A vehicle, in particular a passenger car, comprising a compressed air supply system (1200) for supplying a compressed air consumer via a compressed air supply connection (2), wherein the compressed air supply system (1200) comprises a compressed air generator (200) for providing compressed air (110) at a compressed air connection (1), a pneumatic main line (12) with an air dryer (5, 5.1) for drying and guiding compressed air (110, 120, 120') to the compressed air supply connection (2) in a filling direction (B), and a branch line (14, 14.1, 14.2) branching off from the pneumatic main line (12) in the filling direction (B) upstream of the air dryer (5, 5.1) and reconnecting downstream of the air dryer (5, 5.1, 5.2), a compressed air supply system (1200) associated control device (1300) according to claim 17, and a compressed air consumer (300), in particular a sensor cleaning device (301) connected to a compressed air supply connection (2).

21. Vehicle according to claim 20, further comprising: at least one sensor (9, 400, 410) which is connected to the control device (1300) in a signal-conducting manner and is designed to provide sensor information (S, T, H) for determining a saturation level (G) of the air dryer (5, 5.1, 5.2) and / or a permissible humidity (Hmax), and / or at least one data interface (70), preferably bus (71), in particular CAN bus (72), which is connected to the control device (1300) in a signal-conducting manner and is designed to provide stored sensor information (S, T, H) for determining a degree of saturation (G) of the air dryer (5, 5.1, 5.2) and / or a permissible humidity (Hmax).

22. Vehicle according to claim 20 or 21, further comprising: an on-board electrical system (1600) which is connected to the control device (1300) via the data interface (70) and is designed to provide one, several or all of the following: location information (IGPS) of a navigation system (1600), environmental information (lu) associated with the location information (IGPS), stored sensor information (S, T, H) of an on-board electrical system memory (1610), sensor information (S, T, H) of at least one sensor (400, 410) connected to the on-board electrical system (1600), in particular an ambient temperature sensor (410) and / or a humidity sensor (400), and an on-board electrical system battery (1620) which is designed to supply the on-board electrical system (1600) and / or the compressed air transmitter (200) and / or the compressed air receiver (300) and / or the control device (1300). with current (I), wherein the control device (1300) is preferably designed todepending on the provided sensor information (S, T, H) and / or location information (IGPS) and / or the environmental information (lu), to determine the current and / or predicted temperature (T) of the environment (A) and / or the current and / or predicted humidity (H) of the environment (A) at at least one of the following positions: at a current location (Pi), along a route (P) and at a destination (P3).

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