Device for supplying a breathing gas

Abstract

A device for supplying respiratory gas, which has a respiratory gas supply driven by an electric motor and a motor control system comprising at least one sensor for detecting a measured value, wherein the motor control system (14) has a control characteristic for reducing a current target speed of the electric motor (13) as a function of the measurement signal of the sensor when a predeterminable limit value of an operating parameter is exceeded, characterized in that the motor control system (14) has a control characteristic for reducing the speed as a function of the measured value while simultaneously maintaining a limit value for a further operating parameter, wherein the control characteristic is designed to maintain a minimum value for a ventilation pressure, wherein the motor control system (14) is designed to evaluate at least one detected breathing event,wherein the motor control regulates the mean pressure level in the time range of a user's expiration to at least 2 hPa by means of a control device, and wherein the pressure level in the time range of an expiration is variable independently of a user's specification, and wherein a user can specify the extent of the change in the pressure level for the time range of an expiration, wherein the breathing events are oral expiration and leakage, and wherein, upon automatic detection of these events, the pressure control takes into account those metrological parameters which are evaluated by the control in a normal state for a pressure increase or a pressure decrease and which can no longer be reliably evaluated when these events occur, for the duration of the occurrence of these events,that the operating mode reducing noise and / or energy consumption and / or respiratory effort is activated, with a pressure reduction occurring upon detection of these events.

Description

[0001] The invention relates to a device for supplying a breathing freshening gas to the nasopharyngeal and oral cavity of a user.

[0002] The regulatory criteria for such devices, as well as the measurement methods used to demonstrate compliance with these criteria, are defined in the relevant European and national legislation. Low-noise devices significantly increase user comfort and acceptance, leading to better treatment outcomes.

[0003] In surveys of users who discontinued their ventilation therapy, about 40% cited mask problems as the main disturbing factor and about 19% felt disturbed by the noise of the device.

[0004] Due to the large number of patient interfaces available on the market, the mask problem can often be solved quite quickly by selecting other user interfaces.

[0005] However, various applications outside the field of medical technology are also possible. For example, with ventilators for divers or firefighters, the problem may arise that energy consumption must be minimized when powered by batteries, or that acoustic perception should be impaired by as little background noise as possible. The same problem can also arise in the industrial sector for activities that require the use of ventilators to protect the person concerned from the effects of environmental gases, and where the person concerned does not have their hands free to control the ventilators themselves due to the intended activities. Finally, applications are also conceivable in the field of ventilators used by astronauts or pilots.

[0006] To date, manufacturers have regularly used the approach of surrounding the device with a soundproof capsule / sound insulation solution or dampening the sound as effectively as possible to contain / limit the noise emissions of the device with a view to complying with legal regulations and increasing user compliance. The multitude of solutions known from patents and implemented in practice on devices for supplying a breathing freshener to the nasopharynx and oral cavity of a user makes a specific reference unnecessary here. The sound-reducing measures are designed and materially constructed in such a way that the relevant legal requirements regarding noise reduction / noise limitation are met. However, sound insulation measures have several disadvantages: They significantly increase the number of components, manufacturing costs, and weight.

[0007] In addition, the materials and components used for sound insulation may need to be cleaned and / or replaced regularly.

[0008] DE 101 05 383 A1 discloses a device for supplying breathing gas, which comprises an electric motor, a motor controller, and at least one sensor. A comparable device is also disclosed in US 2005 / 0 103 339 A1.

[0009] Devices with the above-mentioned combination of features are also described in WO 2005 / 013 879 A2 and US 5 199 424 A.

[0010] The object of the invention is therefore to design a low-noise device for supplying a breathing freshener to the nasopharyngeal and oral cavity of a user of the generic type in such a way that costly encapsulation / cladding / sound insulation of the device is at least partially dispensable, while still meeting the statutory requirements regarding sound radiation / noise limitation and increasing user compliance. Furthermore, the weight should remain low.

[0011] The object of the invention is also to provide a method which, in CPAP, bilevel, APAP, titration, home, emergency and hospital devices for supplying a respiratory freshening gas to the nasopharyngeal and oral cavity of a user, which ventilate the user invasively and / or non-invasively, achieves a reduction in noise generation by targeted intervention in the control electronics in those phases in which the user is sufficiently treated and which can be implemented easily and cost-effectively in commercially available devices.

[0012] In a conventional low-noise device for supplying a breathing freshener to the nasopharyngeal and oral cavity of a user with an encapsulated pressurized gas source, which is usually designed as an electric motor with a fan impeller, the operation of the pressurized gas source is regulated by a motor controller based on data stored in a data storage device. Within data limits, motor operation frequently occurs under various functional states, causing noise emissions that are inherently higher than those required by law and / or user acceptance, but can be adequately attenuated through design-based insulation measures.

[0013] According to the invention, the values ​​for power- and / or speed-reducing operation, which are at least partially different from those of standard operation, are stored in free and / or additionally provided data storage locations. Furthermore, the engine control unit is preferably assigned an electronic control unit with a microprocessor, data and program memory, and input and output peripherals, which serves to control the engine control unit for noise-reducing operation of the engine.

[0014] It is a further aspect of the invention to also store the values ​​for energy-saving operation in free and / or additionally provided data storage locations, which are at least partially different from those values ​​of standard operation.

[0015] It is an additional aspect of the invention to store the values ​​for such an operation that reduces the user's work of breathing in free and / or additionally provided data storage locations. These values ​​are at least partially different from those of standard operation.

[0016] The control unit calculates the fan wheel acceleration under specific operating conditions in conjunction with correspondingly signaled operating data and / or events and compares it with predefined acceleration limits stored in its data memory. If these limits are exceeded, the control unit then sends a command to a data memory selection circuit, which then triggers a change to a correspondingly different data set, the values ​​of which are then used to adjust the control system for noise-reduced and / or energy-saving motor operation and / or for reducing the user's exhalation effort.

[0017] These measures are based on empirically obtained knowledge of the noise generation, energy consumption, and respiratory effort of the user of the device in question for supplying a breathing freshener to the nasopharynx and oral cavity. This information reveals, for example, under which operating conditions the legally prescribed noise limits are exceeded. These operating conditions, for example, constitute the events to be used in the invention.

[0018] In addition, characteristic operating states, which usually occur due to a user's breathing maneuvers on the device, constitute control-determining events.

[0019] According to the invention, the legally prescribed sound radiation limit values ​​are to be specified as target values ​​and these are to be used in accordance with the invention in such a way that the device cannot essentially be operated in at least one operating state in such a way that these sound limit values ​​are exceeded.

[0020] In the event of an imminent exceedance of the specified noise limits, control measures are initiated. Noise-reducing engine control measures are initiated when the specified noise limits are imminently exceeded. This occurs in coordination with the user's breathing maneuvers, ensuring that the user's needs are essentially always met.

[0021] In this way, the motor is always automatically set to operate, if necessary independently of the respective user, in such a way that the permissible noise emission limits are not exceeded. In the event that the device for supplying a breathing freshening gas to the nasopharynx and oral cavity of a user also has a fully automated operating mode, the operating mode changes are carried out automatically by the motor control unit or a detection electronics communicating with it, so as not to throttle the breathing gas supply during noise-reducing motor operation.

[0022] In the case of devices for supplying a breathing freshening gas to the nasopharyngeal and oral cavity of a user, which devices have at least two different operating states to be specified by the user and / or an operating state that follows specified patterns, the user preferably receives, when a power and speed reducing line is called up by the control unit and / or such a line can be called up, a visual and / or acoustic indication at the same time that he can switch to a further operating mode in order to be able to continue the operation of the device for supplying a breathing freshening gas to the nasopharyngeal and oral cavity of a user within the range of the characteristic values ​​of the previously selected operating mode, supplemented with control-related changes that result in a reduction in noise and / or energy savings and / or a reduction in the user's work of breathing.

[0023] As a result, the measures according to the invention ensure that the expensive motor encapsulations and / or device encapsulations previously required for sound insulation can either be dispensed with entirely or at least replaced by comparatively inexpensive partial partitions.

[0024] The solution according to the invention is explained in more detail below with reference to embodiments shown in the drawings.

[0025] The drawings illustrate embodiments of the invention. They show: Fig. 1 a basic structure of a device for ventilation with a breathing mask, Fig. 2 a block diagram illustrating an engine control system taking into account current operating data, Fig. 3 a diagram illustrating a pressure reaction to an event, Fig. 4 an example of an event to be detected, Fig. 5 another diagram illustrating event detection and processing, Fig. 6 a schematic representation to illustrate obstructive events, Fig. 7 a further illustration to take obstructions into account, Fig. 8 a diagram illustrating the detection of a so-called flutter state and Fig. 9 a diagram illustrating the course of measured variables during central events.

[0026] Fig. 1 shows the basic structure of a ventilation device. A breathing gas pump is arranged in the interior of the device in the area of ​​a device housing (1) with a control panel (2) and display (3). A connecting hose (5) is connected via a coupling (4). An additional pressure measuring hose (6) can run along the connecting hose (5) and can be connected to the device housing (1) via a pressure inlet nozzle (7). To enable data transmission, the device housing (1) has an interface (8). An exhalation element (9) is arranged in the area of ​​an extension of the connecting hose (5) facing away from the device housing (1). Fig. Figure 1 also shows a user interface (10) designed as a nasal mask. Fixation in the area of ​​a user's head can be achieved via a hood (11). The ventilation mask (10) has a connection piece (12) in the area of ​​its extension facing the connecting tube (5).

[0027] To prevent the airways from drying out, it is particularly useful to humidify the breathing air during longer ventilation phases. Such humidification of the breathing air can also be achieved in other applications. For humidification, adaptable respiratory humidifiers are typically inserted into the airway between the device for supplying a freshening gas to the user's nasopharynx and mouth.

[0028] In addition, an oxygen supply valve can be adapted to supply a user with an increased amount of oxygen with the breathing gas.

[0029] The display preferably shows real-time data. Numerical displays of inspiratory and expiratory pressure, leak, respiratory rate, apnea / hypopnea, tidal volume, minute ventilation, and target ventilation are particularly preferred. Data on pressure, flow, leak, minute ventilation, target ventilation, respiratory rate, tidal volume, flow limitation index, and other events can be exported via the interface. The data can also be stored on the device and transferred via wireless communication.

[0030] Communication can take place via the following interfaces: USB Firewire Bluetooth radio Infrared SMS GSM EDGE WCDMA ZigBee Wi-Fi Infrared.

[0031] Additional modules can be adapted via the interface. One module, for example, monitors arterial oxygen saturation. Data exchange via a removable storage device is also planned.

[0032] It is also planned that data can be read out via an interface and evaluated by external software.

[0033] The drive unit of the device for supplying a breathing freshener to the user's nasopharynx and mouth consists of an electric motor with a fan impeller that accelerates and compresses the air drawn in. Pressure is increased by increasing the fan impeller's speed, while pressure is decreased by decreasing the fan impeller's speed and / or additionally by deliberately increasing a leak.

[0034] The weight of the device for supplying a breathing freshening gas to the nasopharynx and mouth of a user is preferably less than 2.5 kg, particularly preferably less than 2.0 kg, very particularly preferably less than 1.5 kg. The volume of the device for supplying a breathing freshening gas to the nasopharynx and mouth of a user is preferably less than 30 dBA at 10 mbar at a distance of 1 m, particularly preferably less than 27 dBA at 10 mbar at a distance of 1 m, very particularly preferably less than 25 dBA at 10 mbar at a distance of 1 m. The pressure range is preferably in the range 0 to 80 mbar, particularly preferably in the range 2 to 35 mbar. An adjustable ramp time is preferably in the range 0 to 30 min.

[0035] Fig. Figure 2 schematically shows the motor 13, which is supplied with power via a power source (not shown). The operation of the motor 13 and its power control via a corresponding adjustment of the power supply can be controlled by a motor controller 14. This controller has a microprocessor 15, an analyzer 16, at least one data memory 17, and an input peripheral 18 and output peripheral 19. The individual components of the motor controller are linked to one another via a data bus system 20. The motor controller 14 operates on the basis of current operating data or values ​​reported to it by at least one sensor 21, such as gas pressure, gas flow, resistance, ODS signal, gas temperature, other events, selected operating mode, fan speed, motor speed, motor power consumption, and device noise.

[0036] The engine control 14 has a data storage capacity which either has sufficient free memory locations to store the data / values ​​required for the control system according to the invention, or is considerably expanded compared to a control system previously used to control the same engine, whereby this can be achieved by replacing the previously used data memory 17 with a data memory 22 designed for a higher storage capacity, in particular by supplementing the previously used data memory 17 with at least one further data memory 23 or 24 of the same or higher storage capacity.The values ​​which define the predefined and / or automatic operating mode are primarily stored in the data memory 17 and / or 22. In contrast, the values ​​which are at least partially different from those of the standard predefined and / or automatic operating modes are stored in the additional memory locations of the data memory 22, 23, 24 and are used according to the invention for an operation which causes less noise, an energy-saving operation or an operation which reduces the respiratory effort of the user of the device for supplying a breathing freshening gas to the nasopharynx and oral cavity of a user.

[0037] Fig. Figure 3 shows an example of a pressure response to an event. Fig. 4 - 9 show examples of events to be detected.

[0038] The controller for the energy-saving operating mode has an analyzer for detecting at least one event, and the analyzer is coupled to the controller in such a way that the energy-saving operating mode is activated upon detection of the event.

[0039] The controller for the noise-reducing operating mode has an analyzer for detecting at least one event, and the analyzer is coupled to the controller in such a way that the noise-reducing operating mode is activated upon detection of the event.

[0040] The control for the operating mode reducing the user's work of breathing has an analyzer for detecting at least one event, and the analyzer is coupled to the control in such a way that the operating mode reducing the user's work of breathing is activated upon detection of the event.

[0041] Preferably, when an event is detected, a control-specific sequence circuit is activated.

[0042] The device and method according to the invention exploit the fact that specific events lead to typical influences on the measured respiratory parameter. The corresponding typical temporal profiles of the respiratory parameter, which are assigned to a specific event, enable automatic evaluation of the signal profile with regard to the respective profiles and thus control-related identification of the respective event.

[0043] Corresponding specific events that can be identified from the signal curve are, for example, - Oral expiration, - mouth breathing, - Leakage, - Swallow, - Speak, - sneezing, - Cough, - Increase in respiratory flow, - decrease in respiratory flow, - flattening of the respiratory flow, - cessation of respiratory flow, - Increase in resistance, - Leakage, - apnea, - Hypopnea, - snoring, - Cough - sneezing, - Speak, - Swallow, - Inhalation, - exhalation, - breathing space, - Increase in respiratory volume, - decrease in respiratory volume, - inspiratory notch of the respiratory flow, - Increase in the pressure of the breathing fresh gas, - Decrease in the pressure of the breathing fresh gas, - Increase in the flow of respiratory fresh gas, - decrease in the flow of respiratory fresh gas, - Increase in the volume of breathing fresh gas delivered, - Decrease in the volume of breathing fresh gas delivered,

[0044] With automatic detection of such events, it is possible to modify the pressure control in such a way that those measurement parameters which are evaluated by the control system in a normal state for a pressure increase or a pressure decrease and which can no longer be reliably evaluated when the respective event occurs are taken into account by the control system for the duration of the event occurrence in such a way that the operating mode which reduces the noise and / or the energy consumption and / or the work of breathing is activated.

[0045] Based on the occurrence or non-occurrence of events, the device can automatically change its pressure level and / or change its operating state, such as activating or deactivating a specific mode, permanently and / or only during the event. If the detected event is an artifact that causes other parameters to no longer be reliably evaluated, other events can be ignored.

[0046] A typical procedure is carried out by the control system being designed to carry out CPAP, APAP, bilevel, home ventilation, hospital, intensive care, and emergency ventilation.

[0047] According to one embodiment, the analyzer is designed to evaluate a flow profile.

[0048] In addition, it is also considered that the analyzer is designed to evaluate a pressure curve.

[0049] One variant of the method involves the analyzer being designed to evaluate inspiration phases. It is also possible for the analyzer to be designed to evaluate expiration phases.

[0050] A simple evaluation principle involves the analyzer being designed to evaluate amplitude values. It is also possible for the analyzer to be designed to evaluate power values.

[0051] According to a further embodiment, the analyzer is provided with a reference value comparator. Frequency-dependent signal evaluation is supported by bandpass filtering of the measured pressure signal.

[0052] In particular, it is envisaged that a frequency band during bandpass filtering is defined in such a way that the amplitude of a volume oscillation generated by the device is measured. An excitation signal adapted to the bandpass filtering can be provided by generating the volume oscillation using a diaphragm pump.

[0053] A good compromise between simple device-technical feasibility and good evaluation of the excitation signal is to generate a volume oscillation with a frequency of about 20 Hz.

[0054] According to a typical evaluation procedure, an evaluation is carried out in such a way that an expiratory narrowing of the airways is detected by an expiratory increase in the pressure oscillation amplitude compared to a reference value.

[0055] A special variant of disturbance detection consists in an evaluation in such a way that individual or cumulative expiratory constrictions are evaluated as events.

[0056] By storing and evaluating events, it is possible to refine the quality of the response of the device for supplying a breathing freshening gas to the nasopharyngeal and oral cavity of a user when events are detected by a self-learning system.

[0057] The ventilation device comprises a compressed gas source connectable to a user interface, a control unit for the compressed gas source, and a measuring device for detecting at least one respiratory parameter. The control unit is equipped with an adaptation device for changing the pressure provided by the compressed gas source depending on an evaluation of the measured respiratory parameter. The control unit has an analyzer for detecting at least one event. The analyzer is coupled to the control unit in such a way that, upon detection of an event, the device for supplying a respiratory freshening gas to the nasopharynx and oral cavity of a user is switched to an alternative operating mode.

[0058] The ventilation device can be coupled to the nasopharyngeal cavity of a user via a biocompatible, electrically insulating connector for transmitting the fresh breathing gas to the nasopharyngeal cavity of the user. At least one leakage device is provided in the area of ​​the device, which essentially also serves to flush the used exhaled air into the environment. The ventilation device uses an electrically controlled breathing gas source to deliver a substantially positive breathing gas pressure, which can be in the range of 0 to 80 mbar.

[0059] The ventilation device comprises a measuring device and / or a sensor for recording analog signals, from which events can be detected through signal processing and / or pattern recognition. In at least one operating mode, at least two of the following events are recorded within a time range of less than one minute: - Oral expiration, - mouth breathing, - Leakage, - Swallow, - Speak, - sneezing, - Cough, - Increase in respiratory flow, - decrease in respiratory flow, - flattening of the respiratory flow, - cessation of respiratory flow, - Increase in resistance, - Leakage, - apnea, - Hypopnea, - snoring, - Cough - sneezing, - Speak, - Swallow, - Inhalation, - exhalation, - breathing space, - Increase in respiratory volume, - decrease in respiratory volume, - inspiratory notch of the respiratory flow, - Increase in the pressure of the breathing fresh gas, - Decrease in the pressure of the breathing fresh gas, - Increase in the flow of respiratory fresh gas, - decrease in the flow of respiratory fresh gas, - Increase in the volume of breathing fresh gas delivered, - Decrease in the volume of fresh breathing gas delivered,

[0060] The ventilation device preferably has a control device for controlling the supply of fresh respiratory gas in accordance with the events detected by the measuring device in order to set a suitable pressure level which can be in the range 0 hPa to 80 hPa.

[0061] In a typical embodiment, the control device increases the pressure level in at least one operating mode and decreases the pressure level in at least one other operating mode. The control device considers at least one event before decreasing the pressure level, and the decrease in the pressure level is substantially consistent with the user's exhalation phase. The control device typically does not allow the pressure to drop below 2 mbar. In at least one other operating mode, the pressure level is decreased in accordance with the user's exhalation phase, with the pressure being decreased more significantly than in another operating mode.

[0062] In a preferred embodiment, the breathing gas source, the measuring device and the control device are designed in a coordinated interaction as a detection electronics which reduces the exhalation work of a user and / or the energy consumption and / or the noise generation in the initial phase of a pressure reduction.

[0063] In a further preferred embodiment, the pressure level of the breathing gas is increased substantially by increasing the speed of a fan wheel and decreased by decreasing the speed of a fan wheel.

[0064] According to this exemplary embodiment, the control device increases the pressure level in at least one operating mode and reduces it in at least one other operating mode, wherein the control device takes into account at least one event before reducing the pressure level and the reduction in the pressure level is substantially consistent with the exhalation phase of a user. In this case, the control device does not allow the pressure to fall below 2 mbar. When reducing the pressure level in line with the exhalation phase of a user, the control device reduces the pressure more sharply in an initial phase than in another operating mode. By reducing the pressure level of respiratory freshening gas via the electrically controlled respiratory gas source in at least one operating state, the energy consumption and / or noise generation of the device are reduced.

[0065] In at least one operating mode, the measuring device will cause a decrease in the speed of a fan wheel via the control device after detecting at least one event.

[0066] According to a further embodiment, the respiratory gas source, the measuring device, and the control device communicate essentially via an electronic controller. Communication with the electronic controller is established via an interface. The electronic controller can be expanded via the interface to include at least one additional operating mode. This operating mode enables the pressure level to be reduced in accordance with the user's exhalation phase, with the pressure being particularly preferably reduced more sharply in an initial phase, thereby specifically reducing the user's exhalation effort.

[0067] In at least one operating mode, at least one event is taken into account before the pressure level is reduced, whereby a control device does not allow the pressure to fall significantly below 2 mbar and the pressure change occurs essentially in the range between 0 and 0.2 mbar / 1 / min.

[0068] In at least one operating mode, at least one event is taken into account before the pressure level is reduced, whereby the pressure change can be adjusted by the user in the range between 0 and 0.2 mbar / 1 / min.

[0069] According to the invention, the pressure level during a user's inspiration can be increased substantially to over 4 hPa by means of a control device, whereby the user can specify the extent of the pressure increase. Regardless of a user's specification, the pressure level during an inspiration is kept constant for at least 1 second. During the end of an inspiration, the control device controls a reduction in the pressure level and essentially does not allow the pressure to fall below 2 hPa.

[0070] According to the invention, the average pressure level during a user's expiration can be regulated to at least 2 hPa by means of a control device. The pressure level during an expiration can be varied independently of a user's specification. A user can specify the extent of the pressure level change for the expiration period.

[0071] According to a further embodiment, the noise emission of the device in at least one operating mode, measured at any point not far from the maximum external dimension of the device in at least one operating mode, is essentially always below 29 dBa. Preferably, the device is portable, weighs less than 4 kg, and optionally has a power supply that maintains at least one function of the device for more than 2 hours when the device is not powered by a power plug. Mobility can be enhanced by the additional option of connecting to a vehicle's cigarette lighter or to another corresponding power source.

[0072] According to the invention, the noise generation of the device is reduced by at least 1 to 3 dBa by means of a control device in accordance with a change in the pressure level of breathing gas in at least one operating state.

[0073] In the area of ​​the device, a data memory with a capacity of more than 10 kb is preferably provided and, in at least one operating state, relevant data regarding the pressure and / or flow of respiratory gas and / or other events are stored in this memory in a readable manner.

[0074] In the area of ​​the device, a programmable electronic data memory is preferably provided on which essential information for controlling at least one operating mode is stored.

[0075] By communicating with the programmable electronic data memory, at least one modified operating mode can be easily and quickly loaded, which can be executed in the configuration area of ​​the device.

[0076] A particular aspect of the invention is to design the data memory in such a way that it can be replaced and / or filled with new data by an update via the input peripherals, wherein the new data memory and / or the data memory filled with new data preferably receives new data that can establish a new operating mode. Such a new operating mode is characterized in that event detection is carried out by an analyzer and, as a result of an event, the motor control is influenced in such a way that the user's work of breathing is specifically reduced and / or the noise level of the device for supplying a freshening gas to the nasopharynx and oral cavity of a user is lowered and / or the device for supplying a freshening gas to the nasopharynx and oral cavity of a user saves energy and / or the fan wheel rotates at fewer revolutions than before the event.

[0077] Preferably, in the event of incidents, selected from the group: - Deviation from the set pressure by more than 2 hPa - Increase in leakage by more than 2% - Noise emission from the device exceeding 30 dBa measured at any point close to the maximum external dimension of the device - Energy consumption of the device increased by more than 5% in at least one operating mode - Hose system integrity - Heating of the device, in particular a defined inadmissible heating of the device - Power outage

[0078] Signals are generated that are suitable to alert a user to a malfunction of the device.

[0079] A key aspect of the invention is the event-driven control of the electric motor of the respiratory gas supply. Event-driven control can ensure that a predefined limit value for at least one operating parameter is not exceeded. As a secondary condition for this limit value monitoring, it can be implemented in the motor control system that a further limit value for another operating parameter must not be exceeded or undershot. In particular, the aim is to keep the noise emissions and / or energy consumption of the ventilator below predefined limits while still ensuring a minimum ventilation pressure.

[0080] The measurement using the sensor can be directed directly at the operating parameter to be maintained, for example, sound emissions or energy consumption. Sound emissions can be measured directly, for example, via a microphone. Energy consumption can be measured directly via current consumption, for example, at a constant supply voltage. Alternatively, sensory detection is also possible by measuring at least one parameter corresponding to the respective parameter to be monitored. For example, the speed of the respiratory gas delivery system corresponds to sound emissions, while energy consumption can be determined using motor characteristics or based on the respiratory gas flow.

[0081] Further event-driven control of the electric motor can be achieved through direct measurement or indirect detection of breathing events. In particular, the goal here is to consider not only temporally constant limit values, but also functional limit value profiles with regard to the limit values ​​to be observed for an operating parameter. The functional limit value profiles can represent temporal functional profiles or any functional relationships between at least two operating parameters. When several operating parameters are functionally linked, compliance with limit values ​​is particularly important, taking multidimensional limit value profiles into account.

[0082] According to one embodiment, a connecting tube is connected to the device for supplying a respiratory freshening gas to the nasopharyngeal and oral cavity of a user via a coupling. A user interface, which can be designed as a nasal mask, is arranged in the area of ​​an extension of the connecting tube facing away from the device housing. A respiratory humidifier can be introduced into the airway to humidify the respiratory freshening gas. A device housing with a control panel is used to facilitate device operation. A respiratory gas pump, which can be designed as an electric motor with a fan impeller, is arranged in the interior of the device. The operation of the electric motor is controllable via a motor control. The operation of the motor and the power control of the motor are controllable by the motor control. The motor control takes into account measurement data from at least one sensor.Preferably, the sensor detects at least one signal related to the respiratory fresh gas flow. An analyzer uses the signal related to the respiratory fresh gas flow to determine data for characterizing inspiration and expiration phases, in particular the duration of the individual phases, the temporal position of the phases, and, if applicable, pressure and / or volume profiles within the individual phases.

[0083] A detection unit uses the signal associated with the fresh gas flow to determine the difference between the current fresh gas flow and a baseline flow. The baseline flow is the fresh gas flow that occurs without the user breathing. The baseline flow is therefore determined by leaks, purge flow, measurement inaccuracies, and other parameters. The difference determined by the detection unit, or an amount of this difference, is multiplied by a temporally constant proportionality factor within a range of 0 to 0.2 mbar / (liters / min). The target pressure is reduced with a time delay by the amount of the multiplication result. The time delay is typically between 0.001 and 0.5 seconds.

[0084] In at least one operating state, the motor control regulates the fan speed depending on the determined breathing phase such that a substantially constant positive pressure is maintained during the inspiration phase. In at least one further operating state, the motor control regulates the fan speed depending on the determined breathing phase such that a pressure reduction occurs during the expiration phase.

Claims

[1] Device for supplying breathing gas, which has a breathing gas supply driven by an electric motor and a motor control which comprises at least one sensor for detecting a measured value, wherein the motor control (14) has a control characteristic for reducing a current target speed of the electric motor (13) depending on the measurement signal of the sensor when a predeterminable limit value of an operating parameter is exceeded characterized bythat the motor control (14) has a control characteristic for a measured value-dependent speed reduction while simultaneously maintaining a limit value for a further operating parameter, wherein the control characteristic is designed to maintain a minimum value for a ventilation pressure, wherein the motor control (14) is designed to evaluate at least one detected breathing event, wherein the motor control regulates the average pressure level in the time range of an expiration of a user to at least 2 hPa by means of a control device and wherein the pressure level in the time range of an expiration is variable independently of a user specification and wherein a user can specify the extent of the change in the pressure level for the time range of an expiration, wherein the breathing events are oral expiration and leakage and wherein, upon automatic detection of these events, the pressure control those metrological parameters,which are evaluated by the control system in a normal state for a pressure increase or a pressure reduction and which can no longer be reliably evaluated when these events occur, are taken into account by the control system for the duration of the occurrence of these events in such a way that the operating mode reducing noise and / or energy consumption and / or breathing work is activated, whereby a pressure reduction occurs when these events are detected.

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