Air dryer system and method of controlling pneumatic vehicle system

Abstract

An air dryer system and a method of controlling a pneumatic vehicle system are provided. An air dryer system (10) comprises a dryer inlet (1), a dryer outlet (2), a desiccant cartridge (22) and a dryer discharge (3). The air dryer system (10) comprises a purge valve (30) comprising a first purge valve port (31) connected to the dryer inlet (1) and a second purge valve port (32) connected to the dryer outlet (3). The air dryer system (10) comprises a switching valve (40) comprising a first switching valve port (41) connected to the dryer inlet (1), a second switching valve port (42) connected to the desiccant cartridge (22), and a third switching valve port (43) connected to the dryer outlet (3). An air dryer system (10) includes a solenoid valve assembly (59) configured to provide pneumatic control signals (CP1, CP2, CP3, CPR).

Description

Technical Field

[0001] The present invention relates to an air dryer system and a method of controlling a pneumatic vehicle system. The present invention particularly relates to an air dryer system including a pneumatically controllable valve assembly. Background Art

[0002] Many vehicles include one or more pneumatic consuming devices, such as brake cylinders, height adjusting cylinders, and / or sensor cleaning systems, but are not limited thereto. To supply compressed air to the pneumatic consuming device system, a compressor may be provided. For various types of pneumatic consuming devices, it is desirable to reduce the humidity of the compressed air before supplying the compressed air to the pneumatic consuming device. An air dryer including a desiccant cartridge may be installed downstream of the compressor. The air dryer system may be configured to provide desiccant regeneration.

[0003] US2013 / 0195682 A1 and EP 4 112 399 A1 disclose a pneumatic vehicle system including an air dryer system, the air dryer system including at least one pneumatic control valve. EP 4 112 399 A1 discloses a two-chamber air dryer.

[0004] The air dryer may be configured to provide a control pressure signal that interrupts the fluid communication between the air dryer inlet and the desiccant cartridge and causes the compressor to enter an unloaded state where the compressor idles or stops. While such an air dryer may be suitable for many applications, it may be beneficial to provide a more versatile air dryer operation. By way of illustration, it is desirable to provide an air dryer system that is operable such that regeneration can be performed without setting the compressor to an idle mode. Alternatively or additionally, it is desirable to provide an air dryer system that is operable to allow the exhaust of the compressor discharge line connected to the inlet without affecting the pneumatic consuming device system. It is particularly desirable to provide such an air dryer system that can provide the desired additional functionality with a small number of additional solenoid valves and / or the air dryer system can be used in combination with a two-chamber dryer configuration. Summary of the Invention

[0005] The object of the present invention is to provide an air dryer system that can be operated in a more general way and a control method for use with such an air dryer system. In an alternative object, there is provided an air dryer system and a control method in which the air dryer system is operable such that regeneration can be performed without setting the compressor to an unloaded state (e.g., idle or stopped), and / or the air dryer system allows the exhaust of the compressor discharge line without this exhaust affecting the pressure in the pneumatic consumption device system. A further alternative object is to provide such an air dryer system and control method that are operable to provide desired additional functions with a small number of additional solenoid valves and / or that can be used in combination with a two-chamber dryer configuration.

[0006] There is provided an air dryer system and a control method as set forth in the independent claims. The dependent claims define preferred and / or advantageous embodiments.

[0007] According to one aspect, there is provided an air dryer system. The air dryer system includes a dryer inlet, a dryer outlet, a desiccant cartridge, a dryer discharge port, and a pneumatic control valve assembly. The dryer inlet is configured to receive air from a compressor discharge line. The dryer outlet is configured to supply dry air. The desiccant cartridge is configured to receive air from the dryer inlet and provide dry air for output via the dryer outlet. The pneumatic control valve assembly includes a purge valve. The purge valve includes a first purge valve port connected to the dryer inlet and a second purge valve port connected to the dryer discharge port. The purge valve is pneumatically controllable. The pneumatic control valve assembly includes a switching valve. The switching valve includes a first switching valve port connected to the dryer inlet, a second switching valve port connected to the desiccant cartridge, and a third switching valve port connected to the dryer discharge port. The switching valve is pneumatically controllable. The air dryer system further includes a solenoid valve assembly. The solenoid valve assembly includes a first solenoid valve configured to provide a first control pressure signal to control the purge valve. The solenoid valve assembly includes a second solenoid valve configured to provide a second control pressure signal to control the compressor.

[0008] The air dryer system achieves various technical effects. Providing the first solenoid valve and the second solenoid valve allows the air dryer system to provide additional functions, such as enabling the desiccant cartridge to be regenerated without setting the compressor to an unloaded state (such as idle or stopped), wherein the first solenoid valve is configured to provide a first control pressure signal to control the purge valve, the second solenoid valve is separate from the first solenoid valve and the second solenoid valve is configured to provide a second control pressure signal to control the compressor. Providing a pneumatically controllable valve assembly in combination with the solenoid valve assembly also allows the compressor discharge line to be vented without affecting the pneumatic consumption device system that may be directly or indirectly coupled to the dryer outlet.

[0009] The solenoid valve assembly may include a third solenoid valve, which is configured to provide a regeneration control pressure signal to effect regeneration of the desiccant in the desiccant cartridge.

[0010] Thereby, the versatility of the air valve system is further enhanced. Providing a third solenoid valve, which is separate from the first solenoid valve operable to control the purge valve and separate from the second solenoid valve operable to control the compressor, enables the air valve system to provide functions such as reducing the pressure in the supply line even while the compressor is pumping, enabling the desiccant cartridge to be regenerated while reducing or eliminating actions on the compressor discharge line and / or enabling the compressor discharge line to be vented without affecting the pneumatic consumption device system pressure.

[0011] The third solenoid valve may be configured to provide both a regeneration control pressure signal and a third control pressure signal to control the switching valve.

[0012] Thereby, an air dryer system having three solenoid valves (especially for an air dryer system with a single-chamber configuration) or having four or five solenoid valves (for an air dryer system with a double-chamber configuration) can be used to achieve the following functions: on-load operation (wherein the compressor provides compressed air dried by the desiccant cartridge, and the dry air is provided to at least one pneumatic consumption device); off-load operation (wherein the compressor is set to an idle state or stopped); reducing the pressure in the supply line via the air dryer system without the compressor being in an off-load state; regenerating the desiccant cartridge (e.g., by an air flow from the dryer outlet through the air dryer system to the dryer discharge port) without affecting the compressor discharge line connected to the dryer inlet; and venting the compressor discharge line (e.g., via the air dryer discharge port) without affecting the pneumatic consumption device system pressure.

[0013] The solenoid valve assembly may be configured to provide the first control pressure signal, the second control pressure signal, and the regeneration control pressure signal independently of each other.

[0014] Accordingly, various states of the air dryer system can be achieved using the solenoid valve assembly to provide various control pressure signals.

[0015] The solenoid valve assembly can be configured such that the first solenoid valve, the second solenoid valve, and the third solenoid valve are independently controllable.

[0016] Accordingly, the following functions can be achieved by controlling the first solenoid valve, the second solenoid valve, and the third solenoid valve: on-load operation; off-load operation; reducing the pressure in the supply line via the air dryer system without the compressor being in the off-load state; regenerating the desiccant cartridge without affecting the compressor discharge line; and venting the compressor discharge line without affecting the pneumatic consumption device system pressure.

[0017] The air dryer system or the air dryer assembly including the air dryer system may include an electronic control unit (ECU) configured to provide electrical control signals to the solenoid valves of the solenoid valve assembly to control the solenoid valve assembly. The ECU can be configured to generate electrical control signals to control the solenoid valves of the solenoid valve assembly to achieve at least the following functions, including: regeneration without the compressor being in the off-load state; venting the discharge line, and venting the discharge line does not affect the pressure in the supply line connected to the dryer outlet. The ECU can be configured to generate electrical control signals for different solenoid valves of the solenoid valve assembly independently of each other but in a coordinated manner to achieve the desired functions.

[0018] Accordingly, the ECU can control the following functions: on-load operation; off-load operation; reducing the pressure in the supply line via the air dryer system without the compressor being in the off-load state; regenerating the desiccant cartridge without affecting the compressor discharge line; and venting the compressor discharge line without affecting the pneumatic consumption device system pressure.

[0019] The purge valve can have a first purge valve position and a second purge valve position. The purge valve can be configured such that when the purge valve is in the first purge valve position, the purge valve reduces or blocks the air passage between the dryer inlet and the dryer discharge port.

[0020] Accordingly, the purge valve is operable to prevent fluid communication between the dryer inlet and the dryer discharge port via the purge valve, thereby achieving functions such as: supplying dry air via the dryer outlet (establishing fluid communication between the dryer inlet and the desiccant cartridge via the switching valve while preventing fluid communication between the dryer inlet and the dryer discharge port via the purge valve); and regeneration (establishing fluid communication between the desiccant cartridge and the discharge port via the switching valve) without affecting the compressor discharge line connected to the dryer inlet.

[0021] The purge valve can be configured to provide fluid communication between the dryer inlet and the dryer outlet when the purge valve is in a second purge valve position.

[0022] Thereby, the purge valve can be operated to selectively achieve communication between the dryer inlet and the dryer outlet, for example, to vent a compressor discharge line connected to the dryer inlet, where the venting is performed through an air dryer system. In addition to the first solenoid valve, providing a second solenoid valve allows for controlling the purge valve and the compressor such that the compressor is in a pumping state and the purge valve establishes fluid communication between the compressor discharge line and the dryer outlet. Even when the compressor is pumping, the pressure in the pneumatic consumption device system can be reduced.

[0023] The purge valve can be configured such that it is normally in a first purge valve state and selectively transitions to a second purge valve state in response to a first control pressure signal (e.g., when the first control pressure signal is equal to the pressure at the dryer outlet).

[0024] Thereby, the purge valve can be maintained in its rest configuration for the loaded state while being selectively activated to reduce the pressure in the pneumatic consumption device system and / or for venting the discharge line.

[0025] The purge valve can be or can include a 2 / 2-way valve.

[0026] Thereby, the operations mentioned can be achieved in an efficient manner.

[0027] The switching valve can have a first switching valve position and a second switching valve position. The switching valve can be configured to provide fluid communication between the dryer inlet and the desiccant cartridge when the switching valve is in the first switching valve position. The switching valve can be configured to prevent fluid communication between the desiccant cartridge and the dryer outlet when the switching valve is in the first switching valve position.

[0028] Thereby, the switching valve can be operated to establish fluid communication between the dryer inlet and the desiccant cartridge via the switching valve, thereby achieving functions such as supplying dry air via the dryer outlet (where fluid communication between the dryer inlet and the dryer outlet is blocked via the purge valve).

[0029] The switching valve can be configured to provide fluid communication between the desiccant cartridge and the discharge port when the switching valve is in the second switching valve position. The switching valve can be configured to prevent fluid communication between the dryer inlet and the desiccant cartridge when the switching valve is in the second switching valve position.

[0030] Thus, the switching valve is operable to selectively establish fluid communication between the desiccant cartridge and the dryer outlet via the switching valve while preventing fluid communication between the dryer inlet and the desiccant cartridge, thereby achieving functions such as reducing the pressure in the pneumatic consumption device system (e.g., by reducing the pressure in the supply line connected to the dryer outlet, which is performed via the air dryer system) or regeneration.

[0031] The switching valve can be configured such that it is normally in a first switching valve state and selectively transitions to a second switching valve state in response to a third control pressure signal (e.g., when the third control pressure signal is equal to the pressure at the dryer outlet).

[0032] Thus, the switching valve can be maintained in its rest configuration for the on-load state while being selectively activated to reduce the pressure in the pneumatic consumption device system without affecting the compressor discharge line and / or for regeneration.

[0033] The switching valve can be or can include a 3 / 2-way valve.

[0034] Thus, the above operations of the switching valve can be achieved in an efficient manner.

[0035] The air dryer system can include an outlet line (which can also be referred to as a supply port line), where the outlet line includes an outlet check valve and is connected to the desiccant cartridge and the dryer outlet. The regeneration line can include a regeneration check valve and can be in fluid communication with the outlet line at a location between the desiccant cartridge and the outlet check valve. The air dryer system is operable such that providing a regeneration signal to the regeneration line enables air to flow from the pneumatic consumption device system to the desiccant cartridge to perform regeneration.

[0036] Thus, regeneration can be implemented in an efficient manner.

[0037] The solenoid valve assembly can be configured such that each of the first solenoid valve, the second solenoid valve, and the third solenoid valve is operable to output a control pressure signal that can switch between two different signal pressure values (also referred to herein as a first pneumatic signal value and a second pneumatic signal value). These two states can also be represented as logic "0" (e.g., no positive pressure at the solenoid valve output) and logic "1" (the solenoid valve output pressure is equal to the pressure at the dryer outlet).

[0038] Thus, the solenoid valve assembly can be implemented in an efficient manner, where each solenoid valve has an input that is in fluid communication with the supply line or otherwise in fluid communication with the dryer outlet.

[0039] The solenoid valve assembly can be configured such that each of the first solenoid valve, the second solenoid valve, and the third solenoid valve outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output) for the loaded state in which the compressor pumps and the air dryer provides dry air at the dryer outlet. Thus, the solenoid valve assembly is operable to provide a control pressure signal for setting the air dryer assembly to the loaded state.

[0040] Alternatively or additionally, the solenoid valve assembly can be configured such that each of the first solenoid valve and the third solenoid valve outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output), and the second solenoid valve outputs a second pneumatic signal value (e.g., the pressure at the dryer outlet) for the unloaded state in which the compressor is set to unloaded operation (e.g., idle or stopped). Thus, the solenoid valve assembly is operable to provide a control pressure signal for setting the air dryer assembly to the unloaded state.

[0041] Alternatively or additionally, the solenoid valve assembly can be configured such that each of the first solenoid valve and the third solenoid valve outputs a second pneumatic signal value (e.g., the pressure at the dryer outlet), and the second solenoid valve outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output) for reducing the pressure in the pneumatic consumption device system while the compressor continues to pump. Thus, the solenoid valve assembly is operable such that the purge valve is set to the second purge valve state (establishing fluid communication between the dryer inlet and the dryer discharge port), the switching valve is set to the second switching valve state (which blocks fluid communication between the dryer inlet and the desiccant cartridge and establishes fluid communication between the desiccant cartridge and the discharge port), and an air flow from the dryer outlet to the desiccant cartridge is achieved (through the regeneration control pressure signal).

[0042] Alternatively or additionally, the solenoid valve assembly can be configured such that each of the second solenoid valve and the third solenoid valve outputs a second pneumatic signal value (e.g., the pressure at the dryer outlet), and the first solenoid valve outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output) for regeneration. Thus, the solenoid valve assembly is operable such that the compressor is set to unloaded operation (e.g., idle or stopped), the purge valve is in the first purge valve state (blocking fluid communication between the dryer inlet and the dryer discharge port), the switching valve is set to the second switching valve state (which blocks fluid communication between the dryer inlet and the desiccant cartridge and establishes fluid communication between the desiccant cartridge and the discharge port), and an air flow from the dryer outlet to the desiccant cartridge is achieved (through the regeneration control pressure signal). Thus, regeneration is implemented in a manner that has no effect on the compressor discharge line connected to the dryer inlet.

[0043] Alternatively or additionally, the solenoid valve assembly can be configured such that each of the first solenoid valve and the second solenoid valve outputs a second pneumatic signal value (e.g., the pressure at the dryer outlet), and the third solenoid valve outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve outlet) for performing the exhaust of the compressor discharge line. Thus, the solenoid valve assembly is operable such that the compressor is set to an unloaded operation (e.g., idling or stopped), the purge valve is set to a second purge valve state (establishing fluid communication between the dryer inlet and the dryer discharge port), and the switching valve is in a first switching valve state (which blocks fluid communication between the desiccant cartridge and the discharge port through the switching valve). Thus, the compressor discharge line is exhausted without affecting the pneumatic consumption device system pressure.

[0044] The ECU can be configured to generate a first electrical control signal for controlling the first solenoid valve, a second electrical control signal for controlling the second solenoid valve, and a third electrical control signal for controlling the third solenoid valve to provide the various functions herein.

[0045] The air dryer system can include additional desiccant cartridges.

[0046] Thus, the air dryer system can have a two-chamber configuration. This provides the effect of further increasing the lifespan before the cartridge needs to be replaced.

[0047] The air dryer system can include an additional pneumatic control valve assembly, the additional pneumatic control valve assembly including an additional purge valve and an additional switching valve. The additional purge valve can be pneumatically controllable. The additional switching valve can be pneumatically controllable.

[0048] Thus, pneumatic control is implemented for the two chambers of the two-chamber air dryer system. This allows the use of, for example, four or five solenoid valves to achieve various functions.

[0049] The first solenoid valve can be configured to provide a first control pressure signal to control both the purge valve and the additional purge valve.

[0050] Thus, the first solenoid valve can be used to pneumatically control both the purge valve and the additional purge valve.

[0051] The air dryer system can include an additional inlet port and an additional discharge port, wherein the additional inlet port is configured to be coupled to the compressor discharge line. The additional purge valve can be configured to selectively establish fluid communication between the additional inlet port and the additional discharge port. The additional switching valve can be configured to establish fluid communication between the additional desiccant cartridge and one of the additional inlet port and the additional discharge port.

[0052] Accordingly, the additional purge valve and the additional switching valve are configured to operate as explained in connection with the purge valve and the switching valve.

[0053] The solenoid valve assembly may include at least one fourth solenoid valve configured to generate at least one fourth control pressure signal to control at least one of the switching valve and the additional switching valve.

[0054] Accordingly, it is possible to select which one of the desiccant cartridge and the additional desiccant cartridge is used to dry the air received from the compressor discharge line, and which one of the desiccant cartridge and the additional desiccant cartridge will be regenerated.

[0055] The solenoid valve assembly may be configured such that the at least one fourth control pressure signal selects one of the desiccant cartridge and the additional desiccant cartridge to perform desiccant regeneration or air drying.

[0056] Accordingly, it is possible to select which one of the desiccant cartridge and the additional desiccant cartridge is used to dry the air received from the compressor discharge line, and which one of the desiccant cartridge and the additional desiccant cartridge will be regenerated.

[0057] An air dryer is also disclosed. The air dryer may include an air dryer housing and an air dryer system of any aspect or embodiment disclosed herein. The pneumatic control valve assembly may be disposed in the air dryer housing. The solenoid valve assembly may be disposed in the air dryer housing.

[0058] Accordingly, since both the solenoid valve assembly and the pneumatic control valve assembly are disposed in the air dryer housing, ease of installation is achieved.

[0059] In another aspect, the solenoid valve assembly may be provided outside the air dryer and separated from the air dryer. The combination of the air dryer and the solenoid valve assembly is also referred to herein as an air dryer assembly.

[0060] Accordingly, an air dryer assembly is also disclosed. The air dryer assembly may include an air dryer housing and an air dryer system of any aspect or embodiment disclosed herein. The pneumatic control valve assembly is disposed in the air dryer housing. The solenoid valve assembly is disposed outside the air dryer housing and connected to the pneumatic control valve assembly through a pneumatic connection.

[0061] Accordingly, greater flexibility is achieved in positioning the solenoid valve assembly. Providing the solenoid valve assembly separately from the air dryer may also be beneficial for use with a two-chamber air dryer.

[0062] The air dryer housing may have a first control pressure port configured to receive a first control pressure signal, a second control pressure port configured to receive a second control pressure signal, a third control pressure port configured to receive a third control pressure signal, and a regeneration control signal port configured to receive a regeneration control pressure signal.

[0063] Thus, ports configured to receive various pressure control signals are provided on the air dryer housing.

[0064] Also disclosed is a pneumatic vehicle system. The pneumatic vehicle system may include a compressor, an air dryer or an air dryer assembly, a pneumatic consumption device system, a compressor discharge line connecting to the discharge port of the compressor and the dryer inlet, a supply line connecting to the dryer outlet and the pneumatic consumption device system, and an electronic control unit configured to control a solenoid valve assembly.

[0065] Thus, a pneumatic vehicle system is provided in which the air dryer or the air dryer assembly provides enhanced functionality.

[0066] The pneumatic vehicle system may include a pneumatic braking system (such as an electro-pneumatic braking system) and / or a pneumatic leveling system (such as an electro-pneumatic leveling system).

[0067] Also disclosed is a commercial vehicle including the pneumatic vehicle system.

[0068] Thus, a commercial vehicle is provided in which the air dryer or the air dryer assembly provides enhanced functionality.

[0069] According to another aspect, a method of controlling a pneumatic vehicle system is provided. The pneumatic vehicle system includes a compressor and an air dryer. The compressor includes a compressor discharge port, and the air dryer is connected to the compressor discharge port through a compressor discharge line. The air dryer includes a dryer inlet, a dryer outlet, a desiccant cartridge, and a dryer discharge port. The dryer inlet is configured to receive air from the compressor discharge line, the dryer outlet is configured to supply dry air, the desiccant cartridge is configured to receive air from the dryer inlet and provide dry air for output via the dryer outlet. The air dryer further includes a pneumatic control valve assembly. The pneumatic control valve assembly includes a purge valve and a switching valve. The purge valve includes a first purge valve port connected to the dryer inlet and a second purge valve port connected to the dryer discharge port, and the purge valve is pneumatically controllable. The switching valve includes a first switching valve port connected to the dryer inlet, a second switching valve port connected to the desiccant cartridge, and a third switching valve port connected to the dryer discharge port, and the switching valve is pneumatically controllable. The method includes providing a first control pressure signal by a first solenoid valve to control the purge valve, and providing a second control pressure signal by a second solenoid valve to control the compressor.

[0070] Various technical effects are achieved through the control method. By using a first solenoid valve to provide a first control pressure signal to control a purge valve and using a second solenoid valve to provide a second control pressure signal to control a compressor, the air dryer system can provide additional functions. Examples of such functions include enabling the desiccant cartridge to be regenerated without setting the compressor to an unloaded state (such as idle or stopped). By using solenoid valve assemblies in combination with the solenoid valve assemblies, the control method also enables the compressor discharge line to exhaust without affecting the pressure in the supply line connected to the dryer outlet.

[0071] The method may include providing a regeneration control pressure signal through a third solenoid valve to effect regeneration of the desiccant in the desiccant cartridge.

[0072] Thereby, the versatility of the air valve system is further enhanced. A third solenoid valve is provided, which is separate from the first solenoid valve operable to control the purge valve and separate from the second solenoid valve operable to control the compressor, enabling the air valve system to provide functions such as reducing the pressure in the supply line even when the compressor is pumping, enabling the desiccant cartridge to be regenerated while reducing or eliminating actions on the compressor discharge line and / or enabling the compressor discharge line to exhaust without affecting the pneumatic consumption device system pressure.

[0073] The method may include providing both a regeneration control pressure signal and a third control pressure signal by the third solenoid valve to control a switching valve.

[0074] Thereby, various functions can be implemented without significantly increasing the complexity of the solenoid valve assembly.

[0075] The method may further include providing an electrical control signal from an electronic control unit (ECU) to the solenoid valves of the solenoid valve assembly to control the solenoid valve assembly. The method may include generating an electrical control signal by the ECU to control the solenoid valves of the solenoid valve assembly in order to implement at least the following functions, including: regeneration without the compressor being in an unloaded state; and discharging the discharge line, the discharge of the discharge line not affecting the pressure in the supply line connected to the dryer outlet.

[0076] Thereby, the ECU can control various functions of the air dryer assembly.

[0077] Additional features of the control method and the effects achieved thereby correspond to the features disclosed in association with an air dryer system, an air dryer or an air dryer assembly, a pneumatic vehicle system or a commercial vehicle.

[0078] The method may be performed by or using an air dryer system, an air dryer or an air dryer assembly, a pneumatic vehicle system or a commercial vehicle disclosed herein.

[0079] Various effects and advantages are achieved by the air dryer system, air dryer, air dryer assembly, pneumatic vehicle system, commercial vehicle, and control method disclosed herein. The air dryer system is more versatile and provides additional functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] Additional embodiments are defined in the claims. These and other aspects of the invention will be apparent from and more particularly described in the embodiments described with reference to the following drawings, in which:

[0081] Figure 1 is a pneumatic circuit diagram of an air dryer system according to an embodiment;

[0082] Figure 2 is a pneumatic circuit diagram of an air dryer system according to another embodiment;

[0083] Figure 3 is a schematic diagram of a pneumatic system of an air dryer system including Figure 2 ;

[0084] Figure 4 is a schematic diagram of a pneumatic system of an air dryer system including Figure 1 ;

[0085] Figure 5 is a pneumatic circuit diagram of an air dryer system having a dual-chamber configuration according to an embodiment;

[0086] Figure 6 is a pneumatic circuit diagram of an air dryer system having a dual-chamber configuration according to another embodiment;

[0087] Figure 7 is a schematic diagram of a vehicle including a pneumatic vehicle system according to an embodiment;

[0088] Figure 8 is a schematic diagram of a vehicle including a pneumatic braking system according to an embodiment;

[0089] Figure 9 is a schematic diagram of a vehicle including a pneumatic braking system according to an embodiment;

[0090] Figure 10 is a flowchart of a method according to an embodiment;

[0091] Figure 11 is a flowchart of a method according to an embodiment;

[0092] Figure 12 is a schematic diagram of a commercial vehicle including an air dryer system according to an embodiment. DETAILED DESCRIPTION

[0093] Embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, like or identical reference numerals denote elements having like or identical configurations and / or functions.

[0094] To avoid repetition in the drawings and in the description of the various aspects and illustrative embodiments, it should be understood that many features are common to several aspects and embodiments. Omitting an aspect from the description or the drawings does not mean that the aspect is missing from an embodiment that includes that aspect. Rather, the aspect may be omitted for clarity. The same reference numerals in two or more figures denote the same or similar elements.

[0095] An air dryer system, an air dryer, an air dryer assembly, and a pneumatic vehicle system will be described. As used herein, the term "air dryer system" refers to a system that includes components integrated into an air dryer, and it is not required that all components of the air dryer system be structural elements of the air dryer. By way of illustration, an air dryer system according to some embodiments may include a solenoid valve assembly that is separate from and fluidly connected to the air dryer. The term "air dryer assembly" refers to an assembly that includes an air dryer that includes an air dryer system according to an embodiment, or refers to an assembly that includes a solenoid valve assembly and an air dryer that includes at least a pneumatic control valve assembly that can be controlled by the solenoid valve assembly. The air dryer assembly may include additional components such as one or more of a compressor, a compressor discharge line, and / or a supply line. A pneumatic vehicle system includes an air dryer system, a compressor, and at least one pneumatic consumption device system. The at least one pneumatic consumption device system may include, but is not limited to, a pneumatic brake system and / or a pneumatic leveling system. As used herein, the term "pneumatic vehicle system" encompasses electro-pneumatic vehicle systems (such as electro-pneumatic brakes and / or leveling systems).

[0096] Figure 1 A pneumatic circuit diagram of an air dryer system 10 is shown. The air dryer system 10 includes a desiccant cartridge 22, a pneumatically controllable valve assembly including a purge valve 30 and a switching valve 40, and a solenoid valve assembly 59. The air dryer system 10 may include an air dryer 20 having a housing 21. At least the purge valve 30 and the switching valve 40 may be disposed in the housing 21. The desiccant cartridge 22 may be configured to reversibly engage and disengage from the housing 21 in a non-destructive manner.

[0097] The air dryer system 10 has a dryer inlet 1, a dryer outlet 2, and a dryer discharge port 3. The air dryer system 10 is configured to receive air from the compressor discharge line 11 at the dryer inlet 1. The air can be pressurized air having a pressure above ambient pressure. The air dryer system 10 is configured to supply dry air to the supply line 12, thereby supplying dry air to the pneumatic consumption device system. The air dryer system 10 is configured to discharge air through the dryer discharge port 3, for example, during one, several, or all of the regeneration of the desiccant cartridge 22, the venting of the compressor discharge line 11, and the pressure reduction in the pneumatic consumption device system.

[0098] The desiccant cartridge 22 has a desiccant cartridge port 23 and an additional desiccant cartridge port 24. The additional desiccant cartridge port 24 is connected to the outlet line 28. The outlet line 28 is also connected to the dryer outlet 2. The outlet line 28 has an outlet check valve 25.

[0099] The air dryer 20 includes a regeneration line 27. The regeneration line 27 is connected to the outlet line 28 at a position between the additional desiccant cartridge port 24 and the outlet check valve 25. The regeneration line 27 includes a regeneration check valve 26. This configuration allows the regeneration of the desiccant cartridge 22 in response to the provision of a regeneration control pressure signal CPR to the regeneration line 27.

[0100] The air dryer 20 includes a number of control input ports, including a first control input port 4P, a second control input port 4R, and a third control input port 4S. The second control input port 4R is configured to receive a regeneration control pressure signal CPR.

[0101] The purge valve 30 has a first purge valve port 31 and a second purge valve port 32. The first purge valve port 31 is in fluid communication with the dryer inlet 1 via a first purge valve connection line 51. The second purge valve port 32 is in fluid communication with the dryer discharge port 3 via a second purge valve connection line 52. The purge valve 30 is pneumatically controllable. The air dryer system 20 is configured such that the purge valve control input 33 is in fluid communication with the first control input port 4P via a purge valve control signal line 53. By a first control pressure signal CP1, the purge valve 30 can be selectively set to a second purge valve state, in which the purge valve 30 provides an air flow path from the first purge valve port 31 to the second purge valve port 32 and thus to the dryer discharge port 3. The purge valve 30 has a first purge valve state (which can be the rest state of the purge valve 30), in which the purge valve 30 blocks or significantly reduces the air flow from the first purge valve port 31 through the purge valve 30 to the dryer discharge port 3. The purge valve 30 can be implemented as a 2 / 2-way valve.

[0102] The switching valve 40 has a first switching valve port 41, a second switching valve port 42, and a third switching valve port 43. The first switching valve port 41 is in fluid communication with the dryer inlet 1 via a first switching valve connection line 54. The second switching valve port 42 is in fluid communication with the desiccant cartridge port 23 via a second switching valve connection line 55. The third switching valve port 43 is in fluid communication with the dryer discharge port 3 via a third switching valve communication line 56. The switching valve 40 is pneumatically controllable. The air dryer system 20 is configured such that a switching valve control input 44 is in fluid communication with a third control input port 4P via a switching valve control signal line 57. The switching valve 40 has a first switching valve state in which the switching valve 40 provides fluid communication between the first switching valve port 41 and the second switching valve port 42 while preventing fluid communication between the second switching valve port 42 and the third switching valve port 43. The switching valve 40 has a second switching valve state in which the switching valve 40 prevents fluid communication between the first switching valve port 41 and the second switching valve port 42 while providing fluid communication between the second switching valve port 42 and the third switching valve port 43. By a third control pressure signal CP3, the switching valve 40 can be selectively set to the second switching valve state in which the switching valve 40 provides an air flow path from the second switching valve port 44 to the third switching valve port 43 and thus to the dryer discharge port 3. The switching valve 40 can be implemented as a 3 / 2-way valve.

[0103] The air dryer system 10 includes a solenoid valve assembly 59. The solenoid valve assembly 30 is configured to provide a first control pressure signal CP1, a second control pressure signal CP2 for unloading the compressor (e.g., by putting the compressor into an idle mode or stopping), a third control pressure signal CP3, and a regeneration control pressure signal CPR. The solenoid valve assembly 59 includes a first solenoid valve 60 configured to provide the first control pressure signal CP1. The solenoid valve assembly 59 includes a second solenoid valve 70 configured to provide the second control pressure signal CP2. The solenoid valve assembly 59 includes a third solenoid valve 80 configured to provide the regeneration control pressure signal CPR and the third control pressure signal CP3. The first solenoid valve 60, the second solenoid valve 70, and the third solenoid valve 80 can be independently controlled. The first solenoid valve 60, the second solenoid valve 70, and the third solenoid valve 80 can be configured to output a first control pressure value (such as ambient pressure) in their normal solenoid valve state (i.e., in the solenoid valve rest state where the solenoid is not energized). The first solenoid valve 60, the second solenoid valve 70, and the third solenoid valve 80 can be configured to output a second control pressure value in their energized state, and the second control pressure value can be equal to the pressure in the supply line 12. In other words, the first solenoid valve 60, the second solenoid valve 70, and the third solenoid valve 80 can be configured to selectively provide the supply line pressure as a control pressure signal.

[0104] The first solenoid valve 60 may include a first solenoid valve input port 61 and a first solenoid valve output port 62. The first solenoid valve input port 61 is in fluid communication with the supply line 12 via a first solenoid valve input line 64. The first solenoid valve output port 62 is in fluid communication with the first control input port 4P via a first control signal line 63. The first solenoid valve 60 is configured to establish fluid communication between the first solenoid valve input port 61 and the first solenoid valve output port 62 in response to a first electrical control signal S1.

[0105] The second solenoid valve 70 may include a second solenoid valve input port 71 and a second solenoid valve output port 72. The second solenoid valve input port 71 is in fluid communication with the supply line 12 via a second solenoid valve input line 74. The second solenoid valve output port 72 is configured to supply a second control pressure signal CP2 to the compressor via a compressor unload control line 13. The second solenoid valve 70 is configured to establish fluid communication between the second solenoid valve input port 71 and the second solenoid valve output port 72 in response to a second electrical control signal S2.

[0106] The third solenoid valve 80 may include a third solenoid valve input port 81 and a third solenoid valve output port 82. The third solenoid valve input port 81 is in fluid communication with the supply line 12 via a third solenoid valve input line 84. The third solenoid valve output port 82 is in fluid communication with the second control input port 4R via a regeneration control signal line 83. The third solenoid valve output port 82 is in fluid communication with the third control input port 4S via a third control signal line 83. The third solenoid valve 80 is configured to establish fluid communication between the third solenoid valve input port 81 and the third solenoid valve output port 82 in response to a third electrical control signal S3.

[0107] The first solenoid valve 60, the second solenoid valve 70, and the third solenoid valve 80 may be implemented as 3 / 2-way valves (where the third solenoid valve port is in communication with the ambient atmosphere) or 2 / 2-way valves, respectively.

[0108] The solenoid valve assembly 59 may be configured such that each of the first solenoid valve 60, the second solenoid valve 70, and the third solenoid valve 80 outputs a first pneumatic signal value for the loaded state (e.g., no positive pressure at the solenoid valve output ports 62, 72, 82), where the compressor pumps and the air dryer 20 provides dry air at the dryer outlet 2. Thus, the solenoid valve assembly 59 is operable to provide a control pressure signal for setting the air dryer assembly 10 to the loaded state.

[0109] The solenoid valve assembly 59 can be configured such that both the first solenoid valve 60 and the third solenoid valve 80 output a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output ports 62, 82), and the second solenoid valve 70 outputs a second pneumatic signal value (e.g., the pressure at the dryer outlet 2) to unload the compressor (e.g., to set the compressor to an idle mode or stop the compressor). Thus, the solenoid valve assembly 59 is operable to provide a control pressure signal for setting the air dryer assembly 10 to an unloaded state.

[0110] The solenoid valve assembly 59 can be configured such that both the first solenoid valve 60 and the third solenoid valve 80 output a second pneumatic signal value (e.g., the pressure at the dryer outlet 2), and the second solenoid valve 70 outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output port 72) for reducing the pressure in the pneumatic consumption device system while the compressor continues to pump. Thus, the solenoid valve assembly 59 is operable such that the purge valve 30 is set to a second purge valve state (establishing fluid communication between the dryer inlet 1 and the dryer discharge port 3), the switching valve 40 is set to a second switching valve state (which blocks fluid communication between the dryer inlet 1 and the desiccant cartridge 22 and establishes fluid communication between the desiccant cartridge 22 and the discharge port 3), and an air flow from the dryer outlet 2 to the desiccant cartridge 22 is achieved (through the regeneration control pressure signal CPR).

[0111] The solenoid valve assembly 59 can be configured such that both the second solenoid valve 70 and the third solenoid valve 80 output a second pneumatic signal value (e.g., the pressure at the dryer outlet 2), and the first solenoid valve 60 outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output port 72) for regeneration. Thus, the solenoid valve assembly 59 is operable such that the compressor is set to an unloading operation (e.g., idle or stopped), the purge valve 30 is in a first purge valve state (blocking fluid communication between the dryer inlet 1 and the dryer discharge port 3), the switching valve 40 is set to a second switching valve state (which blocks fluid communication between the dryer inlet 1 and the desiccant cartridge 22 and establishes fluid communication between the desiccant cartridge 22 and the discharge port 3), and an air flow from the dryer outlet 2 to the desiccant cartridge 22 is achieved (through the regeneration control pressure signal CPR). Thus, regeneration is implemented in a manner that has no effect on the compressor discharge line 11 connected to the dryer inlet 1.

[0112] The solenoid valve assembly 59 can be configured such that both the first solenoid valve 60 and the second solenoid valve 70 output a second pneumatic signal value (e.g., the pressure at the dryer outlet 2), and the third solenoid valve outputs 80 a first pneumatic signal value (e.g., no positive pressure at the third solenoid valve output port 82) for performing the exhaust of the compressor discharge line 11. Thus, the solenoid valve assembly 59 is operable such that the compressor is set to an unloaded operation (e.g., idling or stopped), the purge valve 30 is set to a second purge valve state (establishing fluid communication between the dryer inlet 1 and the dryer discharge port 3), and the switching valve 40 is in a first switching valve state (which prevents fluid communication between the desiccant cartridge 22 and the discharge port 3 through the switching valve 40). Thus, the compressor discharge line is exhausted without affecting the pneumatic consumption device system pressure (e.g., not affecting the pressure in the supply line 12).

[0113] Accordingly, the solenoid valve assembly 59 in combination with the pneumatically controllable valve assembly including the purge valve 30 and the switching valve 40 is configured to provide a more versatile air dryer system function. In particular, the air dryer system 10 is configured to allow regeneration to be performed without affecting the compressor discharge line 11, and / or to perform the exhaust of the compressor discharge line 11 without affecting the pressure in the pneumatic consumption device system (e.g., not affecting the pressure in the supply line 12). The air dryer system 10 also allows the pressure in the pneumatic consumption device system to be reduced while the compressor is pumping.

[0114] Figure 1 The air dryer system 10 includes a solenoid valve assembly 59 that is separate from the air dryer 20 and in fluid communication with the control input ports 4P, 4S, 4R of the air dryer 20. This configuration provides greater flexibility in positioning the solenoid valve assembly 59. This configuration is also suitable for use in combination with a two-chamber air dryer (as will be explained in more detail with reference to Figure 5 and Figure 6 ).

[0115] Figure 2 An air dryer 20 including the air dryer system 10 is shown. The solenoid valve assembly 59, the purge valve 30, and the switching valve 40 are constituted by the air dryer 20. The solenoid valve assembly 59, the purge valve 30, and the switching valve 40 can be arranged in the housing 21 of the air dryer 20. The desiccant cartridge 22 can be reversibly engaged with and disengaged from the housing 21 in a non-destructive manner.

[0116] The air dryer 20 includes a solenoid valve assembly 59. Accordingly, the housing 21 does not need to have the control input ports 4P, 4R, 4S. The housing 21 has a compressor control output port 4 to provide a second control signal CP2 for unloading the compressor.

[0117] The first solenoid valve input port 61, the second solenoid valve input port 71, and the third solenoid valve input port 81 are in fluid communication with the dryer outlet 2. For illustration, the first solenoid valve input port 61, the second solenoid valve input port 71, and the third solenoid valve input port 81 may be in fluid communication with a portion of the output line 28 between the outlet check valve 25 and the dryer outlet 2.

[0118] The first solenoid valve outlet port 62 is connected to the purge valve control signal line 53, which is also connected to the purge valve control signal input 33. The second solenoid valve outlet port 72 is connected to the compressor control outlet port 4 to provide a second control signal CP2 to the compressor via the compressor unload line 13. The third solenoid valve output port 83 is connected to the switching valve control port 44 via the switching valve control signal line 57. The third solenoid valve output port 83 is also connected to the regeneration line 27.

[0119] The solenoid valve assembly 59, the purge valve 30, and the switching valve 40 are configured to operate as explained in connection with Figure 1 Thus, Figure 2 the air dryer 20 is configured to perform, in particular, the regeneration of the desiccant cartridge 22 without affecting the compressor discharge line 11 and / or the exhaust of the compressor discharge line 11 without affecting the pneumatic consumption device system pressure.

[0120] The housing 22 includes an electrical interface to receive a first electrical control signal S1, a second electrical control signal S2, and a third electrical control signal S3 from an electronic control unit.

[0121] Figure 3 A schematic diagram of a pneumatic vehicle system 90 according to an embodiment is shown. The pneumatic vehicle system 90 includes an air dryer 20, which includes a solenoid valve assembly 59, a purge valve 30, a switching valve 40, and a desiccant cartridge. The air dryer 20 may be constructed and operated as explained with reference to Figure 2 The pneumatic vehicle system 90 includes a compressor 91. The compressor 91 is connected to a compressor intake line 93 having an intake opening for air intake. The compressor 91 is coupled to the air dryer 20 via a compressor discharge line 11 and a compressor unload control line 13. The compressor 91 is operable to enter an unloaded state (e.g., idle or stopped) in response to a second control pressure signal CP2 received via the compressor unload control line 13.

[0122] The pneumatic system 90 includes an electronic control unit 90. The electronic control unit 90 is configured to generate a first electrical control signal S1, a second electrical control signal S2, and a third electrical control signal S3 to control the solenoid valve assembly 59. The electronic control unit 90 interfaces with the solenoid valve assembly 59 via one or more electrical control signal links 98.

[0123] The pneumatic system 90 may include components of a pneumatic consumption device system and / or components for interfacing the air dryer 20 with the pneumatic consumption device system, such as a supply tank 94 connected to the dryer outlet 2 via a supply line 12. The pneumatic consumption device system may include a pneumatic consumption device system reservoir 95 and other pneumatic components, such as a check valve 96.

[0124] Figure 4 A schematic diagram of a pneumatic vehicle system 90 according to an embodiment is shown. The pneumatic vehicle system 90 includes an air dryer 20 and a solenoid valve assembly 59 separate from the air dryer 20. The air dryer includes a purge valve 30, a switching valve 40, and a desiccant cartridge 21. The air dryer 20 and the solenoid valve assembly 59 may be constructed and operated as explained with reference to Figure 1 what follows.

[0125] For an air dryer system 10 having one desiccant cartridge 22 (as shown in Figure 1 , Figure 2 , Figure 3 and Figure 4 ), the air dryer system 10 is operable to provide the various functions discussed herein by generating a control pressure signal using the solenoid valve assembly 59, where the solenoid valve assembly 59 includes a first solenoid valve 60, a second solenoid valve 70, and a third solenoid valve 80. In this case, the air dryer system 10 may be constructed such that the control pressure signals received for the following operations are provided by the first solenoid valve 60, the second solenoid valve 70, and the third solenoid valve 80: on-load operation; off-load operation; reducing the pneumatic consumption device system pressure using a running compressor 91; regeneration without affecting the compressor discharge line 11; and venting the compressor discharge line 12. The air dryer system 10 may be constructed such that the control pressure signals received for the following operations are provided by no more than three different solenoid valves 60, 70, 80: on-load operation; off-load operation; reducing the pneumatic consumption device system pressure using a running compressor 91; regeneration without affecting the compressor discharge line 11; and venting the compressor discharge line 12.

[0126] The solenoid valve assembly 59 may include more than three solenoid valves, for example, when used in a two-chamber air dryer.

[0127] Figure 5 A pneumatic circuit diagram of a pneumatic vehicle system 90 including a compressor 91 and an air dryer system 10 providing a two-chamber air dryer configuration is shown. The air dryer system 10 includes an air dryer 20, an additional air dryer 120, and a solenoid valve assembly including a first solenoid valve 60, a second solenoid valve 70, a third solenoid valve 80, and a fourth solenoid valve 150.

[0128] The air dryer 20 includes a desiccant cartridge 22, a purge valve 30, a switching valve 40, an outlet line 28 including an outlet check valve 25, and a regeneration line 27 including a regeneration check valve 26. The air dryer 20 includes a dryer inlet 1, a dryer outlet 2, and a dryer drain 3. The air dryer 20 includes a first control input port 4S, a second control input port 4P, and a third control input port 4R. These components of the air dryer 20 have been discussed herein and may be constructed and operated as previously described in connection with, for example Figure 1 as discussed.

[0129] The air dryer 20 includes a selection control output port 2C that can be used to select one of the air dryer 20 and another air dryer 120 for on-load operation or for regeneration. The selection control output port 2C is coupled to the outlet line 28 at a location between the desiccant cartridge 22 and the outlet check valve 25.

[0130] The other air dryer 120 may have the same construction as the air dryer 20. This facilitates manufacturing and maintenance. The other air dryer 120 includes another desiccant cartridge 122, another purge valve 130, and another switching valve 140, another outlet line 128 including another outlet check valve 125, and another regeneration line 127 including another regeneration check valve 126. The other air dryer 120 includes another dryer inlet 101, another dryer outlet 102, and another dryer drain 103. The other air dryer 120 includes another first control input port 104S, another second control input port 104P, and another third control input port 104R. These components of the other air dryer 120 may be constructed and operated as previously described in connection with, for example Figure 1 as discussed.

[0131] The other air dryer 120 may include another selection control output port 102C that may be rendered inoperative (e.g., closed) in the other air dryer 120.

[0132] The dryer inlet 1 and the other dryer inlet 101 are connected to the compressor discharge line 11. The dryer outlet 2 and the other dryer outlet 102 are connected to a supply line 12 to supply dry air to a pneumatic consumer device system.

[0133] The first solenoid valve 60 has a first solenoid output port that is in fluid communication with both the first control input port 4P of the air dryer 4P and the other first control input port 104P of the other air dryer 104P. The first solenoid valve 60 is configured to set the purge valve 30 and the other purge valve 130 to a second purge valve state. This causes the purge valve 30 to establish fluid communication between the dryer inlet 1 and the dryer discharge port 3, and causes the other purge valve 130 to establish fluid communication between the other dryer inlet 1 and the other dryer discharge port 103. This is useful for reducing the pneumatic consumption device system pressure while the compressor 91 continues to pump and / or for venting the compressor discharge line 11.

[0134] The second solenoid valve 70 is operable to provide a second control pressure signal to the compressor 91 via the compressor unload control line 13 to selectively unload the compressor 91. The second solenoid valve 70 has a second solenoid valve output port connected to the compressor unload control line 13.

[0135] The third solenoid valve 80 has a third solenoid control output port that is in fluid communication with both the second control input port 4R and the other second control input port 104R. Accordingly, the third solenoid valve 80 is configured to provide a regeneration control pressure signal to the second control input port 4R and the other second control input port 104R (note that only one of the air dryers 20 and the other air dryer 120 is selected for regeneration at any given time).

[0136] The fourth solenoid valve 150 includes a fourth solenoid valve input port 151 that is in fluid communication with the supply line 12. The fourth solenoid valve 150 includes a fourth solenoid valve input port 152 that is in fluid communication with the third control input port 4S of the air dryer 20 via the fourth control signal line 153 to provide a fourth control pressure signal CP4. Accordingly, the air dryer system 10 is configured such that different solenoid valves 150, 80 are provided to control the switching valve 40 (via the fourth solenoid valve 150) and to provide a regeneration control pressure signal (via the third solenoid valve 80). The fourth electromagnetic control valve 50 can be controlled by a fourth electrical control signal S4 that can be generated by the electrical control unit 97.

[0137] The fourth solenoid valve 150 is configured to control the switching valve 40 to implement a selection function, i.e., to select one of the air dryer 20 and the additional air dryer 120 for on-load operation (where the air is dried by the selected one of the air dryer 20 and the additional air dryer 120) and for regeneration (where depending on the output of the fourth solenoid valve, regeneration is performed on one of the air dryer 20 and the additional air dryer 120 for on-load operation). Thus, the fourth solenoid valve 150 implements switching between the desiccant cartridge 22 and the additional desiccant cartridge 122 for on-load operation and regeneration, respectively. To implement such a change, the selection control output port 2C is in fluid communication with the additional third control input port 104S of the additional air dryer 120 via the selection interconnect line 105.

[0138] The solenoid valve assembly 59 can be configured such that each of the first solenoid valve 60, the second solenoid valve 70, the third solenoid valve 80, and the fourth solenoid valve 150 outputs a first pneumatic signal value for the on-load state (e.g., no positive pressure at the solenoid valve output port), in which the compressor pumps and the air dryer 20 provides dry air at the dryer outlet 2. Thus, the solenoid valve assembly 59 is operable to provide a control pressure signal that sets the air dryer assembly 10 to the on-load state, in which the cartridge 22 of the air dryer 20 provides dry air.

[0139] The solenoid valve assembly 59 can be configured such that each of the first solenoid valve 60, the second solenoid valve 70, and the third solenoid valve 80 outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output port), and the fourth solenoid valve 150 outputs a second pneumatic signal value for the on-load state (e.g., the pressure at the supply line 12), in which the compressor pumps and the additional air dryer 120 provides dry air at the additional dryer outlet 102. Thus, the solenoid valve assembly 59 is operable to provide a control pressure signal that sets the air dryer assembly 10 to the on-load state, in which the additional cartridge 122 of the additional air dryer 20 provides dry air. The selection or switching between the cartridges is achieved by the control pressure signal provided by the fourth solenoid valve 150 to the third control input port 4S of the air dryer 20 and then provided to the additional third control input port 104S of the additional air dryer 120 via the selection control output port 2C and the selection interconnect line 105.

[0140] The solenoid valve assembly 59 can be configured such that each of the first solenoid valve 60, the third solenoid valve 80, and the fourth solenoid valve 150 outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output port), and the second solenoid valve 70 outputs a second pneumatic signal value (e.g., the pressure at the supply line 12) to unload the compressor (e.g., to set the compressor to an idle mode or stop the compressor). Thus, the solenoid valve assembly 59 is operable to provide a control pressure signal for setting the air dryer assembly 10 to an unloaded state.

[0141] The solenoid valve assembly 59 can be configured such that both the first solenoid valve 60 and the third solenoid valve 80 output a second pneumatic signal value (e.g., the pressure at the supply line 12), and both the second solenoid valve 70 and the fourth solenoid valve 150 output a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output port 72) for reducing the pressure in the pneumatic consumption device system connected to the supply line while the compressor 91 continues to pump.

[0142] The solenoid valve assembly 59 can be configured such that each of the second solenoid valve 70, the third solenoid valve 80, and the fourth solenoid valve outputs a second pneumatic signal value (e.g., the pressure at the supply line 12), and the first solenoid valve 60 outputs a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output port 72) to perform regeneration of the cartridge 22 of the air dryer 20.

[0143] The solenoid valve assembly 59 can be configured such that both the second solenoid valve 70 and the third solenoid valve 80 output a second pneumatic signal value (e.g., the pressure at the supply line 12), and both the first solenoid valve 60 and the fourth solenoid valve 150 output a first pneumatic signal value (e.g., no positive pressure at the solenoid valve output port 72) for performing regeneration of the additional cartridge 122 of the additional air dryer 120.

[0144] The solenoid valve assembly 59 can be configured such that both the first solenoid valve 60 and the second solenoid valve 70 output a second pneumatic signal value (e.g., the pressure at the dryer outlet 2), and the third solenoid valve 80 outputs a first pneumatic signal value (e.g., no positive pressure at the third solenoid valve output port) for performing exhaust of the compressor discharge line 11. In this case, the output of the fourth solenoid valve 150 can be the first pneumatic signal value or the second pneumatic signal value. Thus, the compressor discharge line is exhausted without affecting the pneumatic consumption device system pressure (e.g., without affecting the pressure in the supply line 12).

[0145] Accordingly, the solenoid valve assembly 59 in combination with the pneumatically controllable valve assembly including purge valve 30, switching valve 40, additional purge valve 130, and additional switching valve 140 is configured to provide a more versatile air dryer system function. In particular, the air dryer system 10 is configured to allow regeneration to be performed separately for cartridge 22 and additional cartridge 122 without affecting the compressor discharge line 11. The air dryer system 10 is configured to exhaust the compressor discharge line 11 without affecting the pressure in the pneumatic consumption device system (e.g., without affecting the pressure in supply line 12).

[0146] For an air dryer system 10 having a two-chamber configuration and including a desiccant cartridge 22 and an additional desiccant cartridge 122, the air dryer system 10 is operable to provide the various functions discussed herein by generating control pressure signals using a solenoid valve assembly 59 including a first solenoid valve 60, a second solenoid valve 70, a third solenoid valve 80, and a fourth solenoid valve 150. In this case, the air dryer system 10 can be constructed such that the control pressure signals received for implementing the following functions are provided by the first solenoid valve 60, the second solenoid valve 70, the third solenoid valve 80, and the fourth solenoid valve 150, where the functions include: a loaded operation of drying using desiccant cartridge 22; a loaded operation of drying using additional desiccant cartridge 122; an unloading operation; reducing the pneumatic consumption device system pressure while the compressor 91 is running; regenerating desiccant cartridge 22 without affecting the compressor discharge line 11; regenerating additional desiccant cartridge 22 without affecting the compressor discharge line 11; and exhausting the compressor discharge line 12.

[0147] The electronic control unit 97 is operable to provide a fourth electrical control signal S4 to control the fourth solenoid valve 150.

[0148] Figure 6 An air dryer system 10 having a two-chamber configuration is shown. The air dryer system 10 includes an air dryer 20 and an additional air dryer 120. Both the air dryer 20 and the additional air dryer 120 can have the same construction and operation as Figure 1 air dryer 20. Compared with Figure 5 the air dryer 20 and the additional air dryer 120 do not have a switching control output port 2C.

[0149] The selection of one of the air dryer 20 and the additional air dryer 120 for on-load operation is performed by the fourth electromagnetic control valve 150 and an additional fourth electromagnetic control valve 160. The additional fourth electromagnetic control valve 160 has an additional fourth solenoid valve input port 161 and an additional fourth solenoid valve output port 162, and the additional fourth solenoid valve output port 162 is connected to an additional third control input port 104S via an additional fourth control signal line 163 to provide an additional fourth control pressure signal CP4'. The additional fourth electromagnetic control valve 160 can be controlled by an additional fourth electrical control signal S4', and the additional fourth electrical control signal S4' can be generated by the electrical control unit 97.

[0150] The solenoid valve assembly 59 is operable such that when either on-load operation or regeneration is being performed, one of the fourth solenoid valve 150 and the additional fourth solenoid valve 160 outputs a first pneumatic signal value (e.g., no positive pressure at the output port), and the other of the fourth solenoid valve 150 and the additional fourth solenoid valve 160 outputs a second pneumatic signal value (e.g., the pressure at the supply line 12). Thereby, the desiccant cartridge 22 or the additional desiccant cartridge 122 is selected to dry the air or be regenerated. Other aspects of the operation of the solenoid valve assembly 59 correspond to those described in conjunction with Figure 5 those.

[0151] For the air dryer system 10 having a two-chamber configuration and including the desiccant cartridge 22 and the additional desiccant cartridge 122, Figure 6 the air dryer system 10 is operable to provide the various functions discussed herein by generating control pressure signals using the solenoid valve assembly 59, where the solenoid valve assembly 59 includes a first solenoid valve 60, a second solenoid valve 70, a third solenoid valve 80, a fourth solenoid valve 150, and an additional fourth solenoid valve 160. In this case, the air dryer system 10 can be constructed such that the control pressure signals received for implementing the following functions are provided by the first solenoid valve 60, the second solenoid valve 70, the third solenoid valve 80, the fourth solenoid valve 150, and the additional fourth solenoid valve 160, where the functions include: on-load operation of drying using the desiccant cartridge 22; on-load operation of drying using the additional desiccant cartridge 122; unload operation; reducing the pneumatic consumption device system pressure while the compressor 91 is running; regenerating the desiccant cartridge 22 without affecting the compressor discharge line 11; regenerating the additional desiccant cartridge 22 without affecting the compressor discharge line 11; and venting the compressor discharge line 12.

[0152] Although Figure 6 the air dryer system 10 requires five solenoid valves, the air dryer system 10 provides enhanced switching consistency and signal independence.

[0153] Figure 7 FIG. 1 is a schematic illustration of a vehicle 170 that includes a pneumatic vehicle system 90. The pneumatic vehicle system 170 includes an air dryer system 10 according to one aspect or embodiment, and the air dryer system 10 may be disposed within an air dryer 20. The pneumatic vehicle system 170 includes a compressor 91, a driver 171 configured to drive the compressor 91, and an intake pipeline 93 having an intake opening for ambient air intake. The pneumatic vehicle system 170 includes a compressor discharge pipeline 11 that is connected to a discharge port of the compressor 91 and is connected to a dryer inlet 1 of the air dryer 20. The pneumatic vehicle system 170 includes a compressor unload control pipeline 13 that is connected to an unload control port of the compressor 91 and is configured to provide a second control pressure signal CP2 to the compressor 91.

[0154] The pneumatic vehicle system 170 includes a pneumatic consumption device system 173. The pneumatic consumption device system 173 includes at least one pneumatic consumption device 174. The pneumatic consumption device system 173 is in fluid communication with a supply pipeline 12 and may be directly connected to the supply pipeline 12. The pneumatic consumption device system 173 may include at least one pneumatic consumption device system valve 175 that is interconnected between the supply pipeline 12 and the at least one pneumatic consumption device 174. The pneumatic consumption device system 173 may further include a pneumatic consumption device system connection 176 that is configured to provide dry air to the at least one pneumatic consumption device 174.

[0155] As previously described, the pneumatic vehicle system 170 may include a tank and / or at least one controllable valve (such as Figure 3 and Figure 4 shown) that is coupled to the supply pipeline 12.

[0156] The vehicle 170 may in particular be a commercial vehicle.

[0157] Figure 8 FIG. 2 shows a schematic illustration of a vehicle 170 that includes a pneumatic vehicle system that includes a pneumatic brake system 180, such as an electro-pneumatic brake system. The vehicle 170 may be a commercial vehicle. The vehicle 170 has a plurality of wheels 179 and a plurality of axles 178, 178'.

[0158] The pneumatic braking system 180 includes a pneumatic consumption device, which includes a plurality of brake cylinders 181. The plurality of brake cylinders 181 are in fluid communication with the output ports of at least one modulator 183, 184. In the illustrated embodiment, the pneumatic braking system 180 includes a front axle modulator 183, which has an electrical control interface 186 connected to the electronic control unit 97 via at least one electrical modulator control line 187. The pneumatic braking system 180 includes a rear axle modulator 184, which has an electrical control interface 186 connected to the electronic control unit 97 via the at least one electrical modulator control line 187. The modulators 183, 184 can also interface with sensors 182, such as wheel speed sensors.

[0159] An air supply system including a compressor 91 and an air dryer system 10 provides dry pressurized air, which can be supplied to the brake cylinders 181 under the control of the modulators 183, 184.

[0160] Figure 9 A schematic view of a vehicle 170 including a pneumatic vehicle system is shown, the pneumatic vehicle system including a pneumatic leveling system 190, such as an electro-pneumatic leveling system. The vehicle 170 can be a commercial vehicle. The vehicle 170 has a plurality of wheels 179 and a plurality of axles 178, 178'.

[0161] The pneumatic leveling system 190 includes a pneumatic consumption device, which includes a plurality of leveling valves 191. The plurality of leveling valves 191 are in fluid communication with the output ports of at least one modulator 193, 194. In the illustrated embodiment, the pneumatic leveling system 190 includes a front axle modulator 193, which has an electrical control interface 186 connected to the electronic control unit 97 via at least one electrical modulator control line 197. The pneumatic leveling system 190 includes a rear axle modulator 194, which has an electrical control interface 186 connected to the electronic control unit 97 via the at least one electrical modulator control line 197. The modulators 193, 194 can also interface with sensors 192, such as distance sensors.

[0162] An air supply system including a compressor 91 and an air dryer system 10 provides dry pressurized air, which can be supplied to the leveling valves 191 under the control of the modulators 193, 194.

[0163] Figure 10It is a flowchart of a method 200 for controlling a pneumatic vehicle system. The method 200 can be automatically executed by or with the air dryer system 10. The method 200 includes generating 201 a first control pressure signal CP1 by a first solenoid valve 60 to control a purge valve 30 of the air dryer system 10. The purge valve 30 can be controlled to selectively establish fluid communication between a dryer inlet 1 and a dryer discharge port 3 via the purge valve 30. Generating the first control pressure signal CP1 can include controlling the first solenoid valve 60 by an ECU 79.

[0164] The method 200 includes generating 202 a second control pressure signal CP2 by a second solenoid valve 70 to be supplied to a compressor 91 via a compressor unload control line 13. The compressor 91 can be controlled to selectively unload the compressor (e.g., idle mode or stop). Generating the second control pressure signal CP2 can include controlling the second solenoid valve 70 by an ECU 79.

[0165] The method 200 includes generating 203 a third control pressure signal CP3 by a third solenoid valve 70 to control a switching valve 40 and a regeneration control pressure signal CPR to be supplied to a regeneration line 27. The switching valve 40 can be controlled to selectively block fluid communication between the dryer inlet 1 and a desiccant cartridge 22, and selectively establish fluid communication between the desiccant cartridge and the dryer discharge port 3. Generating the third control pressure signal CP3 and the regeneration control pressure signal CPR can include controlling the third solenoid valve 80 by an ECU 79.

[0166] In the method 200, various control pressure signals are generated such that the following functions are selectively achieved: loaded operation; unload operation; reducing the pressure in the supply line via the air dryer system without the compressor being in an unloaded state; regenerating the desiccant cartridge without affecting the compressor discharge line; and venting the compressor discharge line without affecting the pneumatic consumption device system pressure.

[0167] Figure 11 It is a flowchart of a method 210 for controlling a pneumatic vehicle system. The method 210 can be performed by an air dryer system 10 such as Figure 5 the air dryer system 10 or Figure 6The air dryer system 10) is automatically executed or executed automatically using the air dryer system 10. The method 210 includes generating 211 a first control pressure signal CP1 by a first solenoid valve 60 to control a purge valve 30 and an additional purge valve 130 of the air dryer system 10. The purge valve 30 can be controlled to selectively establish fluid communication between a dryer inlet 1 and a dryer discharge port 3 via the purge valve 30. The additional purge valve 130 can be controlled to selectively establish fluid communication between an additional dryer inlet 101 and an additional dryer discharge port 103 via the additional purge valve 130. Generating the first control pressure signal CP1 can include controlling the first solenoid valve 60 by an ECU 79.

[0168] The method 210 includes generating 212 a second control pressure signal CP2 by a second solenoid valve 70 to be supplied to a compressor 91 via a compressor unload control line 13. The compressor 91 can be controlled to selectively unload the compressor (e.g., idle mode or stop). Generating the second control pressure signal CP2 can include controlling the second solenoid valve 70 by an ECU 79.

[0169] The method 210 includes generating 213 a regeneration control pressure signal CPR by a third solenoid valve 70 to be supplied to a regeneration line 27 and an additional regeneration line 127. Generating a third control pressure signal CP3 and the regeneration control pressure signal CPR can include controlling the third solenoid valve 80 by an ECU 79.

[0170] The method 210 includes by a fourth solenoid valve 150 ( Figure 5 ) or by a fourth solenoid valve 150 and an additional fourth solenoid valve 160 ( Figure 6 ) generating 214 at least one third control pressure signal to control a switching valve 40 and an additional switching valve 140. The switching valve 40 can be controlled to selectively block fluid communication between the dryer inlet 1 and a desiccant cartridge 22, and selectively establish fluid communication between the desiccant cartridge and the dryer discharge port 3. The additional switching valve 140 can be controlled to selectively block fluid communication between the additional dryer inlet 101 and an additional desiccant cartridge 122, and selectively establish fluid communication between the additional desiccant cartridge 122 and the additional dryer discharge port 103. Generating the at least one third control pressure signal can include controlling the switching valve 40 and the additional switching valve 140 by an ECU 79.

[0171] In method 220, various control pressure signals are generated to selectively achieve the following functions: an on-load operation using the desiccant cartridge 22 for drying; an on-load operation using the additional desiccant cartridge 122 for drying; an off-load operation; reducing the pressure in the supply line via the air dryer system without the compressor being in an off-load state; regenerating the desiccant cartridge 22 without affecting the compressor discharge line; regenerating the additional desiccant cartridge 122 without affecting the compressor discharge line; and venting the compressor discharge line without affecting the pneumatic consumption device system pressure.

[0172] The techniques disclosed herein are particularly applicable in combination with commercial vehicles, but are not limited thereto.

[0173] Figure 12 is a schematic view of a commercial vehicle 220. The commercial vehicle 220 includes at least one pneumatic vehicle system 221. According to an embodiment, the at least one pneumatic vehicle system 220 includes an air dryer system 10.

[0174] Embodiments of the present invention achieve various effects and advantages. By way of illustration, embodiments provide an air dryer system that can be operated in a more general manner and a control method for use with such an air dryer system. The air dryer system and the control method allow regeneration to be performed without having to set the compressor to an off-load state (e.g., idling or stopped) and / or allow venting of the compressor discharge line, and such venting does not affect the pneumatic consumption device system. The air dryer system and the control method provide such functions with a small number of additional solenoid valves. The air dryer system and the control method are easily applicable to a two-chamber air dryer configuration.

[0175] Various modifications can be made in additional embodiments. By way of illustration, although the pneumatic vehicle system can include a pneumatic braking system and / or a pneumatic leveling system, the pneumatic vehicle system can include alternative or additional pneumatic consumption device systems, such as a sensor cleaning system (which can be part of a driver assistance system). By way of further illustration, although an air dryer system having a two-chamber configuration can include two air dryers having the same configuration, the air dryer system can also include two air dryers having different configurations.

[0176] The present disclosure also separately covers all additional features shown in the drawings, even though they may not be described in the foregoing or following description. Moreover, individual alternatives of the embodiments described in the drawings and individual alternatives of their descriptions and features can be detached from the subject matter of the present invention or from the disclosed subject matter. The present disclosure includes the subject matter consisting of the features defined in the claims or exemplary embodiments and the subject matter including said features.

[0177] In addition, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single unit or step may perform the functions of several features recited in the claims. The fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used advantageously. Terms such as "essentially", "about", "approximate", "substantially", etc., in connection with an attribute or a value, also respectively and specifically define exactly the said attribute or the said value. Any reference signs in the claims shall not be construed as limiting the scope.

[0178] List of reference signs (part of the description)

[0179] 1 Dryer inlet

[0180] 2 Dryer outlet

[0181] 2C Select control output port

[0182] 3 Dryer discharge port

[0183] 4. Compressor control output port

[0184] 4P First control input port

[0185] 4R Second control input port

[0186] 4S Third control input port

[0187] 10 Air dryer system

[0188] 11 Compressor discharge line

[0189] 12 Supply line

[0190] 13 Compressor unload control line

[0191] 20 Air dryer

[0192] 21 Housing

[0193] 22 Desiccant cartridge

[0194] 23 Desiccant cartridge port

[0195] 24 Additional desiccant cartridge port

[0196] 25 Outlet check valve

[0197] 26 Regeneration check valve

[0198] 27 Regeneration line

[0199] 28 Outlet line

[0200] 29 Select control line.

[0201] 30 Blow-off valve

[0202] 31 First blow-off valve port

[0203] 32 Second blow-off valve port

[0204] 33 Blow-off valve control input

[0205] 40 Switching valve

[0206] 41 First switching valve port

[0207] 42 Second switching valve port

[0208] 43 Third switching valve port

[0209] 44 Switching valve control input

[0210] 51 First blow-off valve connecting pipeline

[0211] 52 Second blow-off valve connecting pipeline

[0212] 53 Blow-off valve control signal pipeline

[0213] 54 First switching valve connecting pipeline

[0214] 55 Second switching valve connecting pipeline

[0215] 56 Third switching valve connecting pipeline

[0216] 57 Switching valve control signal pipeline

[0217] 59 Solenoid valve assembly

[0218] 60 First solenoid valve

[0219] 61 First solenoid valve input port

[0220] 62 First solenoid valve output port

[0221] 63 First control signal pipeline

[0222] 64 First solenoid valve input pipeline

[0223] 70 Second solenoid valve

[0224] 71 Second solenoid valve input port

[0225] 72 Second solenoid valve output port

[0226] 73 Second control signal pipeline

[0227] 74 Second solenoid valve input pipeline

[0228] 80 Third solenoid valve

[0229] 81 Third solenoid valve input port

[0230] 82 Third solenoid valve output port

[0231] 83 Regeneration control signal pipeline

[0232] 84 Third control signal pipeline

[0233] 85 Third solenoid valve input pipeline

[0234] 90 Pneumatic vehicle system

[0235] 91 Compressor

[0236] 92 Compressor discharge port

[0237] 93 Compressor intake pipeline

[0238] 94 Supply tank

[0239] 95 Pneumatic consumption device system reservoir

[0240] 96 Check valve

[0241] 97 Electronic control unit

[0242] 98 Electrical control signal link

[0243] 99 Control pressure signal pipeline

[0244] 101 Additional dryer inlet

[0245] 102 Additional dryer outlet

[0246] 102C Additional selection control output port

[0247] 103 Additional dryer discharge port

[0248] 104P Additional first control input port

[0249] 104R Additional second control input port

[0250] 104S Additional third control input port

[0251] 105 Selection interconnecting pipeline

[0252] 120 Additional air dryer

[0253] 121 Additional housing

[0254] 122 Additional desiccant cartridge

[0255] 125 Additional outlet check valve

[0256] 126 Regeneration check valve

[0257] 130 Additional purge valve

[0258] 140 Additional switching valve

[0259] 150 Fourth solenoid valve

[0260] 151 Fourth solenoid valve input port

[0261] 152 Fourth solenoid valve output port

[0262] 153 Fourth control signal pipeline

[0263] 160 Additional fourth solenoid valve

[0264] 161 Additional fourth solenoid valve input port

[0265] 162 Additional fourth solenoid valve output port

[0266] 163 Additional fourth control signal pipeline

[0267] 170 Vehicle

[0268] 171 Compressor driver

[0269] 173 Pneumatic consumption device system

[0270] 174 Pneumatic consumption device

[0271] 175 Pneumatic consumption device system valve

[0272] 176 Pneumatic consumption device system connection

[0273] 178, 178’ Axle

[0274] 179 Wheel

[0275] 180 Brake system

[0276] 181 Brake cylinder

[0277] 182 Sensor

[0278] 183, 184 Modulator

[0279] 186 Electric control interface

[0280] 187 Electric modulator control line

[0281] 190 Air spring system

[0282] 191 Air spring

[0283] 192 Sensor

[0284] 193 and 194 Modulators

[0285] 196 Modulator Output

[0286] 197 Electric Modulator Control Line

[0287] 200 Method

[0288] 201 Method Steps

[0289] 202 Method Steps

[0290] 203 Method Steps

[0291] 210 Method

[0292] 211 Method Steps

[0293] 212 Method Steps

[0294] 213 Method Steps

[0295] 214 Method Steps

[0296] 220 Commercial Vehicle

[0297] 221 Pneumatic Vehicle System

[0298] CP1 First Control Pressure Signal

[0299] CP2 Second Control Pressure Signal

[0300] CP3 Third Control Pressure Signal

[0301] CPR Regeneration Control Pressure Signal

[0302] S1 First Electric Control Signal

[0303] S2 Second Electric Control Signal

[0304] S3 Third Electric Control Signal

[0305] S4 Fourth Electric Control Signal

[0306] S4’ Another Fourth Electric Control Signal

Claims

1. An air dryer system (10) comprising: A dryer inlet (1) configured to receive air from a compressor discharge line (11), A dryer outlet (2) configured to supply dried air, A desiccant cartridge (22) configured to receive air from the dryer inlet (1) and provide dried air for output via the dryer outlet (2), A dryer discharge port (3), A pneumatic control valve assembly (30, 40) comprising A purge valve (30) having a first purge valve port (31) connected to the dryer inlet (1) and a second purge valve port (32) connected to the dryer discharge port (3), the purge valve (30) being pneumatically controllable, and A switching valve (40) having a first switching valve port (41) connected to the dryer inlet (1), a second switching valve port (42) connected to the desiccant cartridge (22), and a third switching valve port (43) connected to the dryer discharge port (3), the switching valve (40) being pneumatically controllable, and A solenoid valve assembly (59) comprising A first solenoid valve (60) configured to provide a first control pressure signal (CP1) to control the purge valve (30), and A second solenoid valve (70) configured to provide a second control pressure signal (CP2) to control the compressor (91).

2. The air dryer system (10) according to claim 1, wherein, The solenoid valve assembly (59) further comprises: A third solenoid valve (80) configured to provide a regeneration control pressure signal (CPR) to effect regeneration of the desiccant in the desiccant cartridge (22).

3. The air dryer system (10) according to claim 2, wherein, The third solenoid valve (80) is configured to provide both the regeneration control pressure signal (CPR) and a third control pressure signal (CP3) to control the switching valve (40).

4. The air dryer system (10) according to claim 2 or 3, wherein, The solenoid valve assembly (59) is configured to provide the first control pressure signal (CP1), the second control pressure signal (CP2), and the regeneration control pressure signal (CPR) independently of each other.

5. The air dryer system (10) according to any one of the preceding claims, wherein, The purge valve (30) has a first purge valve position and a second purge valve position, wherein the purge valve (30) is configured such that when the purge valve (30) is in the first purge valve position, the purge valve (30) reduces or blocks the air passage between the dryer inlet (1) and the dryer discharge port (3) through the purge valve (30), and wherein the purge valve (30) is configured to provide fluid communication between the dryer inlet (1) and the dryer discharge port (3) when the purge valve (30) is in the second purge valve position.

6. The air dryer system (10) according to any one of the preceding claims, wherein, The switching valve (40) has a first switching valve position and a second switching valve position, Wherein, the switching valve (40) is configured to provide fluid communication between the dryer inlet (1) and the desiccant cartridge (22) when the switching valve (40) is in the first switching valve position, and wherein, the switching valve (40) is configured to provide fluid communication between the desiccant cartridge (22) and the discharge port when the switching valve (40) is in the second switching valve position.

7. The air dryer system (10) according to any one of the preceding claims, comprising: an additional desiccant cartridge (122), and an additional pneumatic control valve assembly (130, 140), the additional pneumatic control valve assembly (130, 140) including an additional purge valve (130) and an additional switching valve (140), the additional purge valve (130) being pneumatically controllable, and the additional switching valve (140) being pneumatically controllable, wherein, the first solenoid valve (60) is configured to provide the first control pressure signal (CP1) to control both the purge valve (30) and the additional purge valve (130).

8. The air dryer system (10) according to claim 7, comprising an additional inlet port (101) and an additional discharge port (103), the additional inlet port (101) being configured to be connected to the compressor discharge line (11), Among them, the additional purge valve (30) being configured to selectively establish fluid communication between the additional inlet port (101) and the additional discharge port (103), and wherein, the additional switching valve (40) is configured to establish fluid communication between the additional desiccant cartridge (22) and one of the additional inlet port (101) and the additional discharge port (103).

9. The air dryer system (10) according to claim 7 or 8, wherein, The solenoid valve assembly (59) further comprises: at least one fourth solenoid valve (150; 150, 160), the at least one fourth solenoid valve being configured to generate at least one fourth control pressure signal (CP4; CP4, CP4') to control at least one of the switching valve (40) and the additional switching valve (140).

10. The air dryer system (10) according to claim 9, wherein, The solenoid valve assembly (59) is configured such that the at least one fourth control pressure signal (CP4; CP4, CP4') selects one of the desiccant cartridge (22) and the additional desiccant cartridge (122) to perform desiccant regeneration or air drying.

11. An air dryer (20), comprising an air dryer housing (21), and the air dryer system (10) according to any one of the preceding claims, Among them, wherein the pneumatic control valve assembly (30, 40) and the solenoid valve assembly (59) are arranged in the air dryer housing (21).

12. An air dryer assembly (20, 59), comprising an air dryer housing (21), the air dryer system (10) according to any one of the preceding claims, Among them, wherein the pneumatic control valve assembly (30, 40) is arranged in the air dryer housing (21), and Wherein, the solenoid valve assembly (59) is arranged outside the air dryer housing (21) and is connected to the pneumatic control valve assembly (30, 40) through a pneumatic connector (99).

13. A pneumatic vehicle system (90; 180; 190; 221), comprising: a compressor (91), the air dryer (20) according to claim 11 or the air dryer assembly (20, 59) according to claim 12, a pneumatic consumption device system (95; 173; 181, 183, 184; 191, 193, 194), a compressor discharge line (11) that connects the discharge port of the compressor (91) and the dryer inlet (1), a supply line (12) that connects the dryer outlet (2) and the pneumatic consumption device system (95; 173; 181, 183, 184; 191, 193, 194), and an electronic control unit (97) configured to control the solenoid valve assembly (59).

14. A commercial vehicle (220) comprising the pneumatic vehicle system (90; 180; 190; 221) according to claim 13.

15. A method of controlling a pneumatic vehicle system (90; 180; 190; 221), the pneumatic vehicle system (90; 180; 190; 221) comprising a compressor (91) and an air dryer (20), the compressor (91) comprising a compressor discharge port, the air dryer (20) being connected to the compressor discharge port through a compressor discharge line (11), Among them, the air dryer (20) comprising a dryer inlet (1), a dryer outlet (2), a desiccant cartridge (22) and a dryer discharge port (3), wherein the dryer inlet (1) is configured to receive air from the compressor discharge line (11), the dryer outlet (2) is configured to supply dried air, the desiccant cartridge (22) is configured to receive air from the dryer inlet (1) and provide dried air for output via the dryer outlet (2), wherein, the air dryer (20) comprises a pneumatic control valve assembly (30, 40), the pneumatic control valve assembly (30, 40) comprising: a purge valve (30) comprising a first purge valve port (31) connected to the dryer inlet (1) and a second purge valve port (32) connected to the dryer discharge port (3), the purge valve (30) being pneumatically controllable, and a switching valve (40) comprising a first switching valve port (41) connected to the dryer inlet (1), a second switching valve port (42) connected to the desiccant cartridge (22) and a third switching valve port (43) connected to the dryer discharge port (3), the switching valve (40) being pneumatically controllable, wherein, the method comprises: A first control pressure signal (CP1) is provided by a first solenoid valve (60) to control the purge valve (30), and A second control pressure signal (CP2) is provided by a second solenoid valve (70) to control the compressor (91).

Images