Ventilation system for a vehicle cabin in the form of a pressurized cabin
Patent Information
- Application Number
- PCT/EP2026/061012
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-04-16
- Filing Date
- 2026-04-16
- Publication Date
- 2026-10-22
Smart Images
Figure EP2026061012_22102026_PF_FP_ABST
Abstract
Description
[0001] Door lock
[0002] Description
[0003] Technical field:
[0004] The present invention relates to a ventilation system for a vehicle cabin designed as a positive pressure cabin and to a method for changing the air pressure in a vehicle cabin designed as a positive pressure cabin of a vehicle with such a ventilation system.
[0005] State of the art:
[0006] When a vehicle door is closed, regardless of whether it's a standard door or a sliding door, air is typically drawn into the vehicle interior. If this air cannot escape, it creates overpressure inside the vehicle. This overpressure, which builds up during the closing process, can make it difficult to close the door completely, sometimes requiring significant force.
[0007] For this reason, vehicles are often equipped with ventilation slots or pivoting ventilation flaps, allowing air drawn into the vehicle interior when the door is closed to escape and reduce pressure in the cabin. These pivoting ventilation flaps are designed to open due to the surge of air created when the door is closed. When the air pressure inside the cabin and in the surrounding area is approximately the same, the ventilation flap pivots back into the closed position. A spring-loaded return mechanism is usually incorporated for this purpose.
[0008] Some types of vehicles, such as construction machinery, agricultural vehicles, and even industrial trucks, are used in environments that are hazardous to health, particularly those with high levels of dust and / or pollutants. While the air pressure inside conventional road vehicles usually matches the ambient air pressure, it is often desirable for construction machinery or agricultural vehicles to have a higher air pressure inside the cabin than the ambient air pressure. Therefore, construction machinery and agricultural vehicles are frequently equipped with pressurized cabins. This allows the level of pollutants or dust inside the cabin to be kept very low, even when there is a high level of pollutants or dust in the surrounding area.
[0009] One requirement for a pressurized cabin is that it is gas-tight when closed, so that no pressure equalization can take place between the inside of the pressurized cabin and the environment.
[0010] Vehicles with a pressurized cabin therefore have no additional openings through which a burst of compressed air generated when a vehicle door is closed could escape. On the contrary, the purpose of a pressurized cabin is to prevent any kind of leakage.
[0011] Compared to vehicles without a pressurized cabin, which typically have leaks and are therefore not airtight, vehicles with a pressurized cabin require more force to close their doors. This increased force puts significant stress on the door locks, causing them to wear out quickly. Furthermore, there is a risk that the door will not fully engage in the lock. In both cases, the vehicle's movement and / or the high pressure within the cabin can cause the door to unexpectedly open during operation.
[0012] While the installation and use of vent slots is unproblematic in vehicles operated under normal environmental conditions to release a burst of compressed air when a vehicle door is closed, vent slots are completely unsuitable for vehicles, especially construction or agricultural machinery, used in hazardous or dusty environments. Firstly, these vent slots allow pollutants or dust-laden ambient air to enter the vehicle cabin, even when the door is closed. Secondly, the vent slots cause a continuous pressure drop inside the pressurized cabin, so that over time, the level of pollutants or dust increases as the cabin pressure decreases.To avoid this, a relatively large amount of clean air must be constantly introduced into the vehicle cabin to maintain the desired positive pressure. However, this involves considerable costs and effort.
[0013] The existing, pivoting ventilation flaps, with or without a return spring, help in some cases to reduce the problem of the high force required to close a vehicle door in vehicles with a pressurized cabin, but they do not eliminate it entirely. In construction machinery or agricultural vehicles with a pressurized cabin, it is not guaranteed that the pivoting ventilation flaps will return to their initial position after being swung open due to a burst of compressed air and remain fully closed during vehicle operation. This is primarily because not only a burst of compressed air during door closing, but also the positive pressure within the cabin during operation, acts on the pivoting ventilation flap.The consequence of a vent flap not being fully closed during vehicle operation is a pressure drop in the vehicle cabin and / or the ingress of dust- or pollutant-laden ambient air. In construction machinery and agricultural vehicles, this is further complicated compared to conventional road vehicles because they are used in environments where they are subject to vibrations. This means that the pivoting vent flaps can be forced from the closed position to an open position not only due to overpressure but also due to vibrations. It has therefore been shown that the use of pivoting vent flaps that open from a closed position due to a burst of compressed air is problematic in construction machinery and agricultural vehicles.This is particularly problematic in construction machinery or agricultural vehicles with protective ventilation, as the air pressure in the vehicle cabin can drop to a level that poses a health risk to the operator due to the ventilation flap not being completely closed. To eliminate this health risk, appropriate monitoring systems are provided that alert the operator to a drop in cabin pressure. If the cabin pressure falls below a defined threshold, an alarm is triggered. This alarm can be an audible warning or a flashing light. Once an alarm is triggered, the operator must respond, which disrupts the workflow. [Representation of the invention:]
[0014] It is therefore an object of the present invention to provide a device capable of reducing the air pressure when a vehicle door to a vehicle cabin is closed, and which can be used in construction machinery or agricultural machinery where there is positive pressure in the cabin. Furthermore, it is also an object of the present invention to provide a device capable of reducing the air pressure when a vehicle door to a cabin of construction machinery or agricultural machinery subjected to strong vibrations is closed.
[0015] According to the invention, the problem is solved by means of a ventilation system for a vehicle cabin designed as a positive pressure cabin, comprising an air passage into the vehicle cabin, a shut-off device, wherein the shut-off direction is designed to close the air passage into the vehicle cabin gas-tight in a closed state and to open the air passage at least partially in an open state, a door contact sensor, an air pressure sensor, an actuator and a control device, wherein the door contact sensor is designed to detect an operating state of the vehicle door, wherein the air pressure sensor is designed to provide information about the air pressure conditions in the interior of the vehicle cabin and wherein the actuator is designed to actuate the shut-off device depending on the detected operating state of the vehicle door.
[0016] It should be noted that the term vehicle cabin also generally includes a vehicle interior that can be closed off by a vehicle door.
[0017] The vehicle door can be a sliding door or a swing door.
[0018] The door contact sensor can, for example, be a capacitive proximity sensor and / or a sensor integrated into a switch.
[0019] The air pressure sensor can determine the air pressure inside the vehicle cabin and / or the pressure difference between the interior of the vehicle cabin and the external environment. The ventilation system can be operated actively or passively. It can be an active ventilation system, such as in an air conditioning system, where air is deliberately moved, or a passive ventilation system, such as an exhaust system, where the air passively follows external physical parameters, such as existing pressure gradients.
[0020] It is understood that the locking device is not operated solely depending on the detected operating state of the vehicle door, but that other conditions may also exist that have an influence on the operating state of the locking device.
[0021] The control device is designed, among other things, to actuate the actuator and thus the locking device depending on the operating state of the vehicle door.
[0022] The operating status of the vehicle door can be detected using the door contact sensor as well as data from the air pressure sensor. For example, it can be assumed that the vehicle door is closed if the air pressure reaches a predefined value that is higher than the ambient air pressure.
[0023] For example, the specified value could be the target value for the air pressure that should be present in the vehicle cabin during normal operation. Furthermore, it can be assumed that a sudden drop in air pressure inside the vehicle cabin is caused by a vehicle door being opened. If the air pressure drops by a specified value within a short period of time, it is assumed that the vehicle door is in an open operating state.
[0024] The control device is designed, for example, to actuate the actuator and thus the shut-off device based on signals from the door contact sensor. Additionally or alternatively, the control device is designed to actuate the actuator and thus the shut-off device based on air pressure data detected by the air pressure sensor. The control device can therefore communicate with the door contact sensor, the air pressure sensor, and other sensors.
[0025] The control device is preferably an electronic control device, enabling electronic control of the locking device depending on the detected operating state of the vehicle door. The control device can be an independent component or integrated into the actuator. The vehicle door has an open operating state and a closed operating state. Preferably, the locking device is in an open state when the vehicle door is in an open operating state. Depending on the operating mode of the ventilation system, the locking device can be in an open or closed state when the vehicle door is in a closed operating state.
[0026] To prevent the locking device from being accidentally incompletely closed, it preferably has exactly two operating states when the vehicle is in operation and a driver is inside: a closed state and a fully open state. In particular, the locking device, such as a flap, has two limit switches that monitor whether the flap is fully open or closed. The actuator is therefore only capable of fully closing or fully opening the locking device.
[0027] The ventilation system can be operated as a device for changing the air pressure in a vehicle cabin designed as a positive pressure cabin.
[0028] In particular, the ventilation system can be operated as a device for reducing the air pressure when closing a vehicle door to a vehicle cabin, with the help of which it is possible to reduce the overpressure in the vehicle cabin in order to close the vehicle door with less counter-pressure and thus less effort, whereby in the closed operating state of the vehicle door the air passage is gas-tight sealed, so that the vehicle with overpressure cabin can be used as intended.
[0029] In particular, there is the possibility that the actuator opens the locking device when the vehicle door is moved from a closed operating state to an open operating state.
[0030] As soon as the door contact sensor detects that the vehicle door is closed, starting from a situation where it was open, the actuator can ensure that the locking device returns to the closed position. This ensures that, when the vehicle door is closed, no air is exchanged between the vehicle cabin and the environment through the closed air vent, while still allowing the compressed air surge that occurs when the vehicle door is closed to escape through the open air vent.
[0031] It is advantageous that the control device includes a time delay element. This allows the locking device to be activated with a time delay after the door contact sensor detects the signal. For example, the locking device can be switched to the closed position only after a predetermined time has elapsed following the detection of a closed operating state of the vehicle door.
[0032] Additionally or alternatively, the ventilation system can be used as a device to reduce the air pressure inside the vehicle cabin and / or as a purging device for pressurized cabins.
[0033] In a preferred embodiment, the ventilation system comprises a blower and a filter system, which can be controlled or regulated, for example, by means of a control device. In this case, the ventilation system forms a protective ventilation system, and the blower and filter system are part of this protective ventilation system. In a known manner, this supplies clean fresh air to the interior of a vehicle cabin and creates positive pressure within the cabin. The filter system can be selected according to the location and application. In particular, depending on the required dust separation efficiency, the filter system can be a gas filter, a dust filter, or a combination thereof, so that dust and / or aerosols can be separated. The blower is preferably speed-controlled or at least switchable in stages.
[0034] It is advantageous for the locking device to be vibration-resistant and / or shock-resistant. This prevents the locking device from accidentally opening due to vibrations affecting the vehicle cabin. Furthermore, it ensures that the locking device opens fully when needed, regardless of external mechanical influences, and is not blocked in any way.
[0035] Preferably, the actuator therefore comprises an electric drive, in particular an electric motor. An actuator with an electric drive has the advantage of being independent of external parameters that could potentially cause the shut-off device to be actuated. For example, the actuator with an electric drive is independent of the pressure difference between the vehicle cabin and the environment or independent of inertial forces due to vibrations of the vehicle. With the aid of the electrically driven actuator, it is possible to selectively open the air passage to such an extent that the required pressure equalization between the vehicle cabin and the environment occurs as intended, regardless of external parameters.
[0036] Furthermore, the actuator can be used with an electric drive to apply a force that prevents the shut-off device from accidentally opening due to external air pressure or mechanical vibration of the vehicle, thus ensuring that the air passage is gas-tight even during operation of a vehicle.
[0037] Since the actuator is electrically operated, it is advantageous to have a power supply such as a battery.
[0038] To prevent contamination of the vehicle cabin, the shut-off device should be closed whenever the door is in a closed operating position. In particular, the shut-off device should always be closed when the vehicle is parked, the door is closed, and the engine is off. It is therefore advantageous for the actuator to have a battery independent of the vehicle's battery, ensuring operation of the shut-off device even when the engine is not running.
[0039] Preferably, the shut-off device is designed as a flap, ball valve or as perforated plates that can be moved relative to each other.
[0040] In a preferred embodiment, the locking device has a flap that opens towards the vehicle cabin. For example, the locking device is attached to a housing of the vehicle cabin and faces into the interior of the vehicle cabin. This has the advantage that the high pressure in the vehicle cabin acts on the flap and additionally prevents the locking device from accidentally opening due to mechanical impacts.
[0041] Furthermore, it is advantageous that the flap is installed and operated in such a way that it initially moves parallel to the sealing surface of the shut-off device and then opens. The present invention also relates to a vehicle comprising a vehicle cabin designed as a pressurized cabin, a vehicle door and a ventilation system according to one of the preceding claims, wherein the vehicle is preferably a mobile work machine with a pressurized cabin, in particular a construction machine with a pressurized cabin, an agricultural vehicle with a pressurized cabin or a forklift truck with a pressurized cabin.
[0042] All these types of vehicles can be used in dusty or pollutant-laden environments. Typically, such vehicles used in dusty or pollutant-laden environments employ pressurized cabins to reduce the risk of pollutant-laden or dust-laden air entering the cabin, due to the higher air pressure inside the cabin compared to the ambient air.
[0043] If the vehicle door of such a vehicle is in the closed position, the vehicle cabin is sealed gas-tight and there is an overpressure in the vehicle cabin compared to the outside environment.
[0044] For electrically operated actuators, it is advantageous for the ventilation system and the vehicle to have separate, independent power supplies. This ensures that the ventilation system can be operated regardless of the vehicle's operating status.
[0045] In a preferred embodiment, the vehicle cabin has a housing and the air passage is an opening in the housing, with the shut-off device attached to the housing. Alternatively, the vehicle cabin has a housing and the air passage is an opening in the housing, wherein an air duct with two end sections is provided, the air duct opening into the opening in the housing at one end section and the shut-off device being provided at the other end section.
[0046] Furthermore, the present invention includes a method for changing the air pressure in a vehicle cabin designed as a positive pressure cabin of a vehicle with a ventilation system according to the invention, characterized by the following steps:
[0047] Detection of the air pressure inside the vehicle cabin using the air pressure sensor; detection of the operating status of the vehicle door using the door contact sensor and / or using the air pressure inside the vehicle cabin.
[0048] • wherein the vehicle door has an open operating state and a closed operating state,
[0049] • Activation of the locking device depending on the detected operating state of the vehicle door.
[0050] The operating status of the vehicle door can be determined both by means of a door contact sensor and by means of the air pressure inside the vehicle cabin.
[0051] Typically, a target value is set for the air pressure inside the vehicle cabin, which is above atmospheric pressure or above the air pressure outside the cabin. If a first upper threshold value for the air pressure inside the cabin is set, which is above the air pressure outside the cabin, particularly in the range of the target value for the air pressure inside the cabin, it can be assumed that the vehicle door is closed when this first upper threshold value for the air pressure inside the cabin is exceeded. The upper pressure threshold value can therefore be used to determine the operating status of the vehicle door.
[0052] In a preferred method, the locking device is opened when the vehicle door is in an open operating state, and after a change from the open operating state of the vehicle door to the closed operating state of the vehicle door, the locking device is closed again.
[0053] This method is suitable for reducing the air pressure when closing a vehicle door to a vehicle cabin.
[0054] This situation occurs, for example, when the driver enters or exits the vehicle cabin. With the help of the aforementioned design, the driver can close the vehicle door relatively easily after having opened it. The subsequent closing of the locking device ensures that the overpressure in the vehicle cabin can rebuild.
[0055] In a preferred embodiment, when the vehicle door is opened to reduce the air pressure when closing the vehicle door into the vehicle cabin, the door contact sensor detects an open operating state of the vehicle door and sends a signal to the actuator to open the locking device. The transmission of the signal from the door contact sensor to the actuator can be carried out by means of a control device. When the vehicle door is closed again, the door contact sensor detects a closed operating state of the vehicle door and sends a signal to the actuator to close the locking device. During the closing process, the locking device is in the open position, so that the air pressure surge generated when the vehicle door is closed can escape through the open locking device.
[0056] As an alternative to the described methods for reducing air pressure when closing a vehicle door to a vehicle cabin, the operating state of the vehicle door can be determined instead of the door contact sensor by means of the first upper threshold for the air pressure in the interior.
[0057] The locking device can be activated immediately after the vehicle door changes from the open to the closed operating state. Preferably, however, the locking device closes with a time delay after the change from the open to the closed operating state of the vehicle door, in order to quickly and effectively expel the air inside the vehicle cabin.
[0058] For example, the actuator can have a time delay module so that the locking device is only closed with a short delay of a few seconds after the vehicle door is closed.
[0059] Furthermore, it is advantageous that the shut-off device is closed at a low speed to prevent the shut-off device itself from generating a burst of compressed air when closing.
[0060] In a vehicle with a pressurized cabin, the positive pressure in the cabin can be restored when the shut-off device is closed. It is important that the shut-off device, when the cabin is closed, seals the air passage gas-tight both when the vehicle is stationary and when it is in operation. The ventilation system and the derived method for reducing the air pressure in the cabin when the vehicle door is closed ensure that the door closing process requires less force and does not affect the air pressure in the cabin during vehicle operation.
[0061] In a further preferred embodiment, a setpoint for the air pressure in the vehicle cabin and a second upper threshold for the air pressure in the vehicle cabin are defined, wherein the second upper threshold for the air pressure in the vehicle cabin is higher than the setpoint for the air pressure in the vehicle cabin and wherein the locking device is opened when the second upper threshold for the air pressure in the vehicle cabin is exceeded and the vehicle door is in a closed operating state.
[0062] In a beneficial further development, a first lower threshold value for the air pressure in the vehicle cabin is set, which is equal to or below the target value for the air pressure in the vehicle cabin. The open locking device closes when the lower threshold value for the air pressure in the vehicle cabin is undershot and the vehicle door is in a closed operating state.
[0063] This method is suitable for regulating the overpressure in a vehicle cabin during operation, i.e., when the vehicle with a pressurized cabin is at the deployment site. In particular, it allows for the reduction of undesirably high pressure in the pressurized cabin without the need to open a vehicle door.
[0064] While a protective ventilation system ensures that clean air enters the vehicle cabin, it cannot prevent contaminants from entering the cabin via other sources. Examples of such sources include an open vehicle door when entering or exiting the cabin, or contaminated clothing or shoes worn by the driver.
[0065] In a preferred embodiment of the method, an additional purging mode is provided, which is initiated when purging conditions are present. The purging mode serves, in particular, to remove contaminated air from the interior of the vehicle cabin. The purging mode can be performed during the intended operation of the vehicle, i.e., while the vehicle is in operation and a driver may be inside the cabin, or when the vehicle is parked and no driver is present.
[0066] Preferably, the purging conditions include a trigger signal, wherein the trigger signal is at least one of the following: exceeding a previously defined threshold of a quality parameter of the air inside the vehicle cabin, exceeding a predetermined time signal, transition from the open operating state of the vehicle door to the closed operating state of the vehicle door.
[0067] Air quality parameters can include, among other things, the CO2 content or dust levels in the vehicle cabin. Alternatively, specific time intervals can be programmed after which a purge cycle is initiated. When a time interval has elapsed, a signal can be sent to start the purge cycle. Furthermore, the purge cycle can be initiated after the vehicle door is opened.
[0068] In this process, it is advantageous if the blower is speed-controlled or a two-stage fan is used.
[0069] In a preferred advanced training mode, a third upper threshold for the air pressure in the vehicle cabin is defined, which is above atmospheric pressure or above the air pressure outside the vehicle cabin. The purge mode is initiated when the air pressure exceeds this third upper threshold, the vehicle door is in a closed operating state, and a trigger signal is present. This is a first-type purge mode that occurs during normal vehicle operation.
[0070] In an advantageous embodiment of this method, the air pressure inside the vehicle cabin is additionally increased to a value above the third upper threshold, the air pressure inside the vehicle cabin preferably being controllable by means of the shut-off device. This is a second type of purging mode when the vehicle is parked. In this embodiment of the method, after the purging mode has been started, the air pressure in the cabin can be increased to a value above the third upper threshold for air pressure. The air pressure can, for example, reach the maximum value that an existing blower or fan can supply. This has the advantage that the maximum possible volume of air is available for purging. Regulation of the air pressure in the cabin can then be achieved, for example, via the shut-off device, in particular via a flap of the shut-off device.In this case, it is advantageous if the locking device can assume not only two end positions but also intermediate positions. Due to the high pressure in the vehicle cabin, this method is particularly suitable when the vehicle is parked and no driver is inside.
[0071] The purging process can be stopped if a stop criterion is present, where the stop criterion is at least one of the following: open operating state of the vehicle door, falling below the third upper threshold for the air pressure in the vehicle cabin, falling below a previously defined lower threshold of a quality parameter of the air inside the vehicle cabin, exceeding a predetermined time interval.
[0072] Since the contaminated air is discharged via the air passage of the shut-off device during the rinsing process, and not via the filter system as was previously the norm, the service life of the filter system can be significantly extended.
[0073] The purging process can also be used to regulate air quality parameters such as the CO2 content of the air or the dust content in the air.
[0074] Brief description of the drawings:
[0075] Preferred embodiments are explained in more detail with reference to the accompanying drawings, which show:
[0076] Fig. 1 shows a schematic representation of a vehicle with a ventilation system according to a first embodiment suitable for reducing the air pressure when closing a vehicle door to a vehicle cabin and for rinsing operations.
[0077] Fig. 2 shows a schematic representation of a vehicle with a ventilation system according to a second embodiment, suitable for reducing the air pressure when a vehicle door to a vehicle cabin is closed, for regulating the air pressure inside the vehicle cabin, and for purging operations. Fig. 3 shows a schematic representation of a vehicle with a ventilation system according to a third embodiment, suitable for reducing the air pressure when a vehicle door to a vehicle cabin is closed, for regulating the air pressure inside the vehicle cabin, and for purging operations.
[0078] Ways to implement the invention and its industrial applicability:
[0079] Fig. 1 shows a schematic representation of a vehicle 10 with a ventilation system 12 according to a first embodiment, wherein the ventilation system 12 is designed as a device for reducing the air pressure when a vehicle door 14 to a vehicle cabin 16 is closed. It is also suitable for carrying out rinsing processes as described below.
[0080] Vehicle 10 is a construction or agricultural vehicle with a pressurized cabin, i.e., a vehicle cabin 16, in which there is positive pressure compared to the surrounding environment. The positive pressure in the vehicle cabin 16 is achieved by ensuring that the cabin 16 is gas-tight when closed and by supplying clean air to the cabin 16 while closed. Access to the vehicle cabin 16 is provided by the vehicle door 14. The vehicle cabin 16 typically has windows, which, however, cannot be opened.
[0081] For the driver's comfort, an air conditioning system, heating, and a filter system are provided. For the sake of clarity, these are not shown in Fig. 1. The air pressure and composition of the air in the vehicle cabin 16, and thus the quality of the air in the vehicle cabin 16, are monitored by means of corresponding sensors (not shown) and a control device (not shown). In particular, an air pressure sensor (not shown) is located inside the vehicle cabin 16 to detect the overpressure in the vehicle cabin 16.
[0082] Vehicle door 14 is a sliding door. Alternatively, vehicle door 14 can be designed as a swing door.
[0083] Regardless of whether the vehicle door 14 is designed as a sliding door or a swing door, closing the vehicle door 14 generates a pressure surge that leads to a pressure increase in the vehicle cabin 16. The higher air pressure in the vehicle cabin 16 compared to the surrounding environment means that a force opposes the closing of the vehicle door 14, requiring increased force to close it. In pressurized vehicle cabins 16, the situation is further complicated by the fact that the already relatively high pressure within the cabin cannot dissipate the pressure surge due to the gas-tight construction of the cabin. For this reason, the ventilation system 12 is provided.
[0084] The ventilation system 12 includes a door contact sensor 20, a control device 22, a shut-off device 24 in the form of a flap and an actuator 26 in the form of an electric drive with an electric motor that actuates the shut-off device 24.
[0085] The door contact sensor 20 is a capacitive proximity sensor. However, it can also be designed as a switch. The door contact sensor 20 detects whether the vehicle door 14 is in an open or closed operating state.
[0086] The control device 22 is an electrical control device. A time delay element may be provided in the control device 22.
[0087] The shut-off device 24 has an open state and a closed state. By means of the actuating device 26, which includes an electric drive with an electric motor, the shut-off device 24 can be moved from the open state to the closed state and vice versa. Intermediate states between an open state and a closed state are not provided outside of a second type of flushing mode described below.
[0088] The actuating device 26 with an electric drive not only ensures that the locking device 24 is moved from an open state to a closed state, but also that in the closed state of the locking device 24 a force is applied which holds the locking device 24 in the closed state against possible external forces, for example due to vibrations of the vehicle 10 or due to pressure equalization.
[0089] The control device 22 is connected via appropriate communication channels 28 to the door contact sensor 20 and the actuator 26, and optionally to the shut-off device 24. The communication channels 28 can be cables or radio links. The vehicle cabin 16 has a housing 30 with an opening 32 into which a channel 34 opens. The opening 32 serves as an air passage and can be located at any suitable point in the vehicle cabin 16. The shut-off device 24 is attached to the other end of the channel 34 and, when closed, seals the channel 34 gas-tight. When the shut-off device 24 is open, the channel 34 is permeable to air and provides a connection between the vehicle cabin 16 and the environment.
[0090] When the vehicle door 14 is open, the door contact sensor 20 detects this and sends a signal to the control device 22. The control device 22 in turn sends a signal to the actuator 26 of the shut-off device 24 and the shut-off device 24 is opened, so that the channel 34 is permeable to air.
[0091] When the previously open vehicle door 14 is closed, a burst of air pressure is generated, which can be discharged to the outside through the channel 34. This usually occurs within a few milliseconds. As soon as the vehicle door 14 is closed, the door contact sensor 20 detects this and sends a signal to the control device 22. The control device 22, in turn, sends a signal to the actuator 26, so that the shut-off device 24 is closed by means of the electric drive. This usually occurs after a short delay. When the shut-off device 24 is fully closed, overpressure can build up again in the vehicle cabin 16, since the vehicle cabin is gas-tight.
[0092] Although not shown, an independent power supply for the ventilation system 12 in the form of a battery is provided, so that the shut-off device 26 can also be operated when the engine of the vehicle 10 is switched off.
[0093] In the illustrated embodiment, the shut-off device 26 is a flap. Alternatively, a ball valve can be provided. The use of perforated plates that can be slid against each other is also conceivable.
[0094] In an embodiment not shown, channel 34 is omitted. If the vehicle's structural conditions permit, the shut-off device can be attached directly to the vehicle cabin housing.
[0095] The vehicle can be designed as a tracked vehicle or as a wheeled vehicle. Fig. 2 shows a schematic representation of the vehicle 10 with a ventilation system 112 according to a second embodiment, wherein the ventilation system 112 is both a device for reducing the air pressure when closing a vehicle door 14 to a vehicle cabin 16 and a device for regulating the air pressure inside the vehicle cabin 16 as well as a device for rinsing a vehicle cabin 16.
[0096] Figure 2 differs from the embodiment shown in Figure 1 in that the control device 122 is additionally connected to the air pressure sensor 140, which is located inside the vehicle cabin 16. Figure 2 explicitly shows the air pressure sensor 140, as well as the blower 150 and the filter system 160 of an air conditioning or protective ventilation system. Fresh air enters the interior of the vehicle cabin 16 by means of the blower 150 and the filter system 160.
[0097] Fig. 3 shows a schematic representation of the vehicle 10 with a ventilation system 212 according to a third embodiment. The embodiment of a ventilation system 212 shown in Fig. 3 differs from the embodiment of a ventilation system 112 shown in Fig. 2 in that the shut-off device 224 is installed inside the vehicle cabin 16.
[0098] The shut-off device 224 is an adjustable flap with a sealing surface that closes the opening 32, which is designed as an air passage. The flap is adjusted parallel to the opening 32 of the air passage and moves from the closed to the open position into the interior of the vehicle cabin. In doing so, the flap is first moved parallel to the sealing surface of the shut-off device and then pivoted.
[0099] This embodiment has the advantage that the high air pressure inside the vehicle cabin 16 acts on the flap, thus providing additional protection against accidental opening.
[0100] The embodiments shown in Figs. 2 and 3 function like the embodiment shown in Fig. 1 as a device for reducing the air pressure when closing a vehicle door 14 to a vehicle cabin 16.
[0101] In the methods described in connection with Figures 1, 2 and 3, the operating state of the vehicle door is detected by means of the door contact sensor 20. As an alternative to the previously described method for reducing the air pressure when closing a vehicle door to a vehicle cabin, in the embodiments shown in Figures 2 and 3, the air pressure prevailing inside the vehicle cabin 16 can be used as an indicator of the operating state of the vehicle door 14 instead of the door contact sensor 20.
[0102] In the proper operation of vehicle 10, a target value for the air pressure is provided which is above atmospheric pressure or above the air pressure outside the vehicle cabin, so that there is an overpressure in the vehicle cabin.
[0103] First, an initial upper threshold for the interior air pressure is defined. This threshold should be above atmospheric pressure or the outside air pressure, and below or equal to the target pressure inside the vehicle. If this threshold is exceeded, the system interprets the vehicle door as being closed.
[0104] The embodiments shown in Figures 2 and 3 are able to regulate the air pressure inside, in particular to reduce it.
[0105] For this purpose, the air pressure sensor 140, which is installed inside the vehicle cabin 16, is connected to the control device 122 of the ventilation system 112; 212.
[0106] Furthermore, a second upper threshold value for the air pressure in the vehicle cabin 16 is defined. This value is above the target value for the air pressure in the vehicle cabin 16, which is required for the proper operation of the vehicle 10. Additionally, a first lower threshold value for the air pressure in the vehicle cabin 16 is defined, which is equal to or below the target value for the air pressure in the vehicle cabin 16, which is required for the proper operation of the vehicle 10.
[0107] The air pressure sensor 140, located inside the vehicle cabin 16, detects the air pressure inside the cabin. The operating status of the vehicle door 14 is also detected. The detection of the vehicle door's operating status can be carried out using the door contact sensor 20, as described in connection with Fig. 1, or, as described above, using the air pressure inside the vehicle cabin 16. If the control device 122 detects an air pressure value above the second upper threshold, the shut-off device 24; 224 opens and releases the opening 32 if the vehicle door 14 is closed. Air can then escape through the opening 32, thus reducing the air pressure inside the vehicle cabin 16.If the lower threshold for the air pressure in the vehicle cabin 16 is undershot and the vehicle door 14 is in a closed state, the open locking device 24; 224 is closed again.
[0108] The ventilation systems 12; 112; 212 shown in Figures 1 and 2 can also be used as a device for purging the vehicle cabin 16 in order to clean the vehicle cabin when the air in the vehicle cabin 16 is contaminated. A controlled air exchange in the vehicle cabin 16 is possible with the aid of the ventilation system 12; 112; 212.
[0109] Two types of flushing modes are distinguished. The first type of flushing mode occurs while the vehicle is in operation, while the second type of flushing mode occurs when the vehicle is parked and in operation.
[0110] In the first type of purge mode, the ventilation system 12; 112; 212 is switched from a standard mode to a purge mode. The change from a standard mode to a purge mode can be initiated by various signals.
[0111] Standard mode is understood to be the mode of the ventilation system 12; 112; 212 when the vehicle 10 is operated as intended, for example when it is in use on a construction site and it is intended that the driver is inside the vehicle cabin 16.
[0112] The purging mode is only performed if the pressure inside the vehicle cabin 16 is higher than outside the vehicle cabin 16. Therefore, a third upper threshold for air pressure is defined for the purging mode, which is above atmospheric pressure or above the air pressure outside the vehicle cabin 16.
[0113] To initiate the flushing mode, at least one trigger signal must be present; that is, flushing conditions must exist. For example, the flushing mode can always be initiated automatically after a change in the operating state from open to closed vehicle door 14. In this case, the trigger signal is the transition from an open to a closed operating state of vehicle door 14.
[0114] Furthermore, air quality parameters can trigger a signal. In an additional or alternative embodiment, a parameter describing the quality of the air inside the vehicle cabin 16 is therefore first defined and detected by means of corresponding sensors located in the vehicle cabin 16.
[0115] Parameters that measure the air quality in the vehicle cabin and can be recorded include, for example, the CO2 concentration or the dust concentration inside the vehicle cabin. Furthermore, an upper and, if applicable, a lower threshold value is defined for the selected parameter to describe the air quality. This could, for example, be an upper and a lower threshold value for the CO2 concentration inside the vehicle cabin.
[0116] The transition from standard mode to purge mode is initiated when the upper threshold for the selected parameter, such as the CO2 content of the air inside the vehicle cabin 16, is exceeded.
[0117] If the vehicle door 14 is closed and the air pressure value is above the third upper threshold for air pressure, the purging process in purging mode is started after a trigger signal by opening the shut-off device 24; 224. Fresh, purified air enters the interior of the vehicle cabin 16 by means of the blower 150 and the filter system 160. The used or contaminated air inside the vehicle cabin 16 is discharged from the vehicle cabin 16 via the open air vent 34.
[0118] In one variant of this procedure, the second type of purge mode, the air pressure inside the vehicle cabin 16 is increased to a value above the third upper threshold after the purge mode has been initiated. An existing blower or fan can supply the maximum possible volume of air to the vehicle cabin 16 at its maximum output, allowing the air pressure to reach its maximum possible value. The maximum possible volume of air is now available for the purge process. The air pressure in the cabin can then be regulated, for example, via the shut-off device, specifically via a flap on the shut-off device. In this case, unlike the standard mode, the shut-off device can assume not only two end positions but also intermediate positions.
[0119] If the lower threshold for the selected parameter, such as the CO2 content of the air inside the vehicle cabin 16, is undershot, the purging process is stopped and the ventilation system 12; 112; 212 switches from purging mode to standard mode. The lower threshold for the selected parameter serves as the stop criterion. The shut-off device 24; 224 is then closed again.
[0120] If no lower threshold value exists for the selected parameter, the rinsing process can also be automatically stopped after a predefined time period, and the system can switch from rinsing mode to standard mode. The elapsed time interval can therefore also serve as a stop criterion.
[0121] It is understood that a fourth upper threshold of air pressure can be set, which serves as an upper limit to switch off the blower 150 again, so that an excessive increase inside the vehicle cabin 16 is prevented.
[0122] In an alternative embodiment, instead of the value for the air quality inside the vehicle cabin 16, a time interval for an operating duration can be defined, so that the switch from standard mode to purge mode occurs at regular intervals. Time intervals can be defined for both standard mode and purge mode.
[0123] Incidentally, the purge mode not only makes it possible to maintain air exchange in the vehicle cabin, but also to regulate various parameters that describe the quality of the air.
Claims
23 Patent claims:
1. Ventilation system for a vehicle cabin designed as a positive pressure cabin, comprising an air passage (32) into the vehicle cabin (16) of the vehicle (10), a shut-off device (24; 224), wherein the shut-off direction (24; 224) is designed to close the air passage (32) into the vehicle cabin (16) gas-tight in a closed state and to open the air passage (32) at least sectionally in an open state, a door contact sensor (20), an air pressure sensor (140), an actuating device (26) and a control device (22, 122, 222), wherein the door contact sensor (20) is designed to detect an operating state of the vehicle door (14), wherein the air pressure sensor (140) is designed to provide information about the air pressure conditions inside the vehicle cabin (16), and wherein the actuator (26) is designed to actuate the locking device (24; 224) depending on the detected operating state of the vehicle door (14).
2. Ventilation system according to claim 1, characterized in that the vehicle door (14) has an open operating state and a closed operating state and the locking device (24; 224) is in the open state when the vehicle door (14) is in an open operating state and the locking device (24; 224) is in the closed or open state when the vehicle door (14) is in a closed operating state.
3. Ventilation system according to one of the preceding claims, characterized in that the control device (22; 122, 222) has a time delay element.
4. Ventilation system according to one of the preceding claims, characterized in that the ventilation system (12; 112; 212) comprises a blower (150) and a filter system (160).
5. Ventilation system according to one of the preceding claims, characterized in that the actuating device (26) comprises an electric drive, in particular an electric motor.
6. Ventilation system according to one of the preceding claims, characterized in that the shut-off device (24; 224) is designed as a flap, ball valve or as perforated plates that can be displaced relative to each other.
7. Ventilation system according to one of the preceding claims, characterized in that the shut-off device (24; 224) has a flap that opens towards the vehicle cabin.
8. Vehicle comprising a vehicle cabin (16) designed as a pressurized cabin, a vehicle door (14) and a ventilation system (12; 112; 212) according to one of the preceding claims.
9. Vehicle according to claim 8, characterized in that the ventilation system (12; 112; 212) a first power supply and the vehicle (10) has a second power supply.
10. Vehicle according to one of claims 9 or 10, characterized in that the vehicle cabin (16) has a housing (30) and the air passage (32) is an opening in the housing (30), wherein the shut-off device (24; 224) is attached to the housing, or that the vehicle cabin (16) has a housing (30) and the air passage (32) is an opening in the housing, and that an air duct (34) with two end sections is provided, wherein the air duct (34) opens into the opening in the housing (30) at one end section and the shut-off device (24; 224) is provided at the other end section.
11. Method for changing the air pressure in a vehicle cabin designed as a positive pressure cabin of a vehicle with a ventilation system according to one of claims 1 to 7, characterized by the following steps: Detection of the air pressure inside the vehicle cabin (16) using the air pressure sensor (140) • Detection of the operating status of the vehicle door (14) using the door contact sensor and / or using the air pressure inside the vehicle cabin (16) • wherein the vehicle door (14) has an open operating state and a closed operating state, • Actuation of the locking device depending on the detected operating state of the vehicle door (14).
12. Method according to claim 11, characterized in that a first upper threshold for the air pressure in the interior, which is above the air pressure outside the vehicle cabin (16), is set and that a closed operating state of the vehicle door (14) is detected when the first upper threshold for the air pressure in the interior of the vehicle cabin (16) is exceeded.
13. Method according to claim 11 or 12, characterized in that the locking device is opened when the vehicle door (14) is in an open operating state and that the locking device is closed again after a change from the open operating state of the vehicle door (14) to the closed operating state of the vehicle door (14).
14. Method according to claim one of claims 11 to 13, characterized in that the locking device (24; 224) is closed with a time delay after the change from the open operating state of the vehicle door (14) to the closed operating state of the vehicle door (14) has taken place.
15. Method according to one of claims 11 to 14, characterized in that a setpoint for the air pressure in the vehicle cabin (16) and a second upper threshold for the air pressure in the vehicle cabin (16) are defined, wherein the first upper threshold for the air pressure in the vehicle cabin (16) is higher than the setpoint for the air pressure in the vehicle cabin (16) and wherein the shut-off device (24; 224) is opened when the second upper threshold for the air pressure in the vehicle cabin (16) is exceeded and the vehicle door (14) is in a closed operating state.
16. Method according to claim 15, characterized in that a first lower threshold value for the air pressure in the vehicle cabin (16) is set, which 26 is equal to or below the target value for the air pressure in the vehicle cabin (16), and the open locking device (24; 224) is closed when the lower threshold for the air pressure in the vehicle cabin (16) is undershot and the vehicle door (14) is in a closed operating state.
17. Method according to one of claims 11 to 16, characterized in that an additional rinsing mode is provided which is started when rinsing conditions are present.
18. Method according to claim 17, characterized in that the purging conditions include a trigger signal, wherein the trigger signal is at least one of the following: exceeding a previously defined threshold value of a quality parameter of the air inside the vehicle cabin (16), exceeding a predetermined time signal, transition from the open operating state of the vehicle door (14) to the closed operating state of the vehicle door (14).
19. Method according to one of claim 18, characterized in that a third upper threshold for the air pressure in the vehicle cabin (16), which is above the air pressure outside the vehicle cabin (16), is set and the purge mode is started when the value of the air pressure in the vehicle cabin (16) is higher than the third upper threshold for the air pressure in the vehicle cabin (16), the vehicle door (14) is in a closed operating state and a trigger signal is present.
20. Method according to one of claims 17 to 19, characterized in that the air pressure inside the vehicle cabin (16) is increased to a value above the third upper threshold value, wherein the air pressure inside the vehicle cabin (16) is preferably controllable by means of the shut-off device (24; 224).
21. Method according to one of claims 17 to 20, characterized in that the rinsing process is stopped when a stop criterion is present, wherein the stop criterion is at least one of the following: open operating state of the vehicle door (14), falling below the third upper threshold for the air pressure in the vehicle cabin (16), falling below a previously defined lower threshold of a quality parameter of the air inside the vehicle cabin (16), exceeding a predetermined time interval.