Control arrangement for ventilated protective clothing

Abstract

The invention relates to a control arrangement (12) for a ventilation assembly for protective clothing (1) covering at least the head of a user, having a blower (7) with a throughput which can be controlled by a control unit (8). A pressure sensor (9) is provided for determining the air pressure in the interior of at least the head region (2) of the protective clothing (1). A computing unit (11) is used to determine the pressure profile with respect to time in the interior of at least the head region (2) of the protective clothing (1), and from this to automatically determine the current air requirement of the user and to generate a control signal to the blower (7).

Description

[0001] CONTROL ARRANGEMENT FOR VENTILATED PROTECTIVE CLOTHING

[0002] The invention relates to a control arrangement for the ventilation arrangement for protective clothing covering at least the head of the user, with artificial ventilation by means of a fan with a throughput controllable via a control unit, comprising a pressure sensor for the air pressure inside at least the head region of the protective clothing, according to the preamble of claim 1.

[0003] EP 3399881A2 discloses a control device for a protective hood with an integrated fan for the air supply. Signals from motion sensors for the head movements of the protective hood wearer are processed in an evaluation unit and used to control the speed of the fan. Sensors for, for example, the CO2 content, humidity, etc. can also be present. From this data, which, however, disregards the user's breathing characteristics, the microclimate in the hood is determined. This data is used to determine the user's stress or physical strain and activity, and the fan speed is automatically adjusted.

[0004] A blower filter system, for example, for respiratory protection devices or the like, is disclosed in DE 102016009486 A1, with a differential pressure sensor between the interior of the headpiece and its surroundings. A control device implements breathing phase detection and breathing rate monitoring, which, however, serves only for error detection, primarily negative pressure situations within the headpiece, and signaling, and is not used for demand-oriented adaptation of the air supply, i.e., for controlling the blower. This device also has a CO2 sensor.

[0005] DE 102015122316 A1 describes a wearable individual air purification system that may include, among other things, a protective mask covering the mouth and nose. A fan supplies a volume flow of filtered air to the mask. Sensors in the protective mask determine the air requirement based on values ​​such as respiratory rate, heart rate, or movement speed, and adjust the volume flow accordingly. No other respiratory parameters other than frequency are taken into account.

[0006] Finally, DE 102010031260 A1 discloses a respiratory protection device with a compressed air cylinder and a pressure regulator for the user. Furthermore, a device for determining respiratory rate, inhalation depth, respiratory gas consumption, and / or exhaled gas composition is provided, with a simple variant including a pressure sensor. Information about the respiratory rate and / or the respiratory volume and / or the respiratory gas consumption is recorded from the pressure profile over time. This information is used to detect emergency situations; however, no influence on the volume flow of the breathing air is, and is not possible, based on this information.

[0007] It was therefore the object of the present invention to overcome the disadvantages of the prior art and to provide a device in which, by means of a simple and energy-efficient arrangement, the user is supplied with breathable air in the best possible and safe way at all times, with high wearing comfort and safety, even if the load on the user and thus his oxygen requirement change quickly and / or significantly.

[0008] To achieve this object, a control arrangement for protective clothing provided with artificial ventilation is proposed, which according to the invention is characterized by a computing unit designed to determine the temporal pressure profile inside at least the head region of the protective clothing and, from this, automatically determine the user's current air requirement, and to generate a control signal to the blower in order to adjust the throughput of the blower depending on this air requirement. The combination of control unit and blower, which is typically powered by batteries or accumulators, is preferably designed to provide a minimum throughput of 401 / min and a maximum throughput of 1501 / min for protective hoods and from 501 / min to 4501 / min for full-protection suits. The computing unit is preferably designed to smooth the signal before output to the blower control unit.This allows the wearer of the protective clothing to be optimally and safely supplied with physiologically correct breathing air, in addition to comfort and flexible application. The air volume is adjusted to the user's current physical exertion and thus their oxygen requirements. Specifically, this also ensures that the CO2 content in the breathing air remains below a specified limit at all times. Adaptive adjustment, particularly of the fan speed, also reduces energy consumption and noise emissions, thus enabling not only a more comfortable wear but also a longer runtime with consistent battery capacity.

[0009] Preferably, the computing unit is designed to determine a preferably moving average of the air pressure inside the protective clothing and to generate a signal to the control unit in order to adjust the throughput of the blower according to a monotonically increasing transfer function of the amount of the difference between the moving average and the current air pressure.

[0010] A further optimization of the adjustment of the air supply into the protective clothing is achieved by an embodiment of the invention in which the computing unit is designed to determine a moving average of the air pressure and to generate a signal in order to adjust the throughput of the blower according to a monotonically increasing transfer function of the sum or the integral over a certain period of time of the amount of the difference between the moving average and the current air pressure.

[0011] According to a preferred embodiment of the invention, the computing unit is designed to generate the signal for adjusting the fan's throughput in such a way that it promptly follows an increase in the difference between the moving average and the current air pressure and / or the sum or integral over a specific period of the difference between the moving average and the current air pressure, while adopting changes in the opposite direction with a time delay. This always ensures a sufficient air supply without giving the wearer the feeling of undersupply when physical exertion decreases. At the same time, this can reduce the number of deceleration and, above all, highly energy-intensive acceleration processes of the fans.Alternatively or additionally, with the same advantage, it can optionally also be provided that the computing unit is designed to generate the signal for adjusting the flow rate of the fan in such a way that it follows an increase in the amount of the difference between the moving average and the current air pressure and / or the sum or the integral over a certain period of time of the amount of the difference between the moving average and the current air pressure to a large extent, and only adopts changes in the opposite direction to a fraction.

[0012] The control arrangement for the blower, designed in accordance with the above paragraphs, allows the current air requirement, which depends on the physical strain and activities of the user, to be determined quickly and reliably using only one pressure sensor and ensures that sufficient breathing air is always available.

[0013] According to a further embodiment of the invention, a control arrangement is characterized in that the computing unit is designed to determine the rate of change in the amount of the difference between the moving average and the current air pressure and / or the sum or integral, and to effect a change in the signal for adjusting the fan throughput according to a monotonically increasing transfer function of this change. This enables a faster change in the signal to the fan with predictive correction.

[0014] Preferably, an advantageous variant of this control arrangement is characterized in that the computing unit is designed to effect the change in the signal for adjusting the throughput of the blower in a weighted manner according to the distance of an envelope curve over the sum or the integral over a certain period of time of the amount of the difference between the moving average and the current air pressure and the current value of this sum or the integral.

[0015] A control arrangement according to the invention can further optionally comprise a computing unit that generates a signal to the control unit as a monotonically increasing transfer function, preferably as a proportionality factor, for adjusting the throughput of the blower between a predeterminable minimum throughput and a predeterminable maximum throughput. In addition to the above-defined control based on pressure measurement, a further embodiment of a control arrangement according to the invention could be equipped with a CO2 sensor and a computing unit that is designed to generate a signal to the control unit to increase the throughput of the blower according to a monotonically increasing transfer function of the CO2 content and / or to generate a warning signal when a limit value for the CO2 content is exceeded, at least in the head region within the protective clothing.This provides a safety function in case the rapid regulation of pressure or breathing rate, which is adapted to the user's breathing air requirements, fails or is disturbed.

[0016] A preferred embodiment of a control arrangement according to the invention further provides that, for example in the control unit, a safety algorithm is implemented which, in the event of a non-measurable and / or non-existent pressure change, initiates at least one predeterminable action, in particular initiates a warning signal and / or switches the fan into a safety mode in which it delivers a constant, predefined air quantity.

[0017] A further advantageous embodiment of a control arrangement according to the invention is characterized in that the control unit is connected to or contains a detector unit for the insertion of the breathing air filter or a grid cover, and is designed to start the fan only after detection of a properly connected breathing air filter or grid cover.

[0018] To achieve the object stated at the outset, protective clothing is proposed, in particular a protective hood covering at least the head of the user or a full-protection or full-body protective suit, with artificial ventilation by means of a fan with a flow rate of breathing air that can be controlled via a control unit and a pressure sensor connected to the control unit for the air pressure at least in the head area within the protective clothing.

[0019] Such protective clothing is characterized according to the invention by a computing unit according to one of the preceding paragraphs, which is designed to determine the current air requirement of the user from the temporal pressure curve and to generate a control signal to the fan in order to adjust the throughput of the fan proportional to this air requirement.

[0020] Preferably, the protective clothing is further characterized by a throttle arrangement for the air flowing out of the head region. This throttle arrangement amplifies the pressure changes in the head region of the protective clothing, which contains the pressure sensor, caused by the wearer's physical activity, thereby simplifying and more precisely analyzing and evaluating the pressure signals.

[0021] A preferred design, which is particularly simple and safe to use, features an elastic and / or adjustable collar as the lower limit of the head area and a restrictor. This allows for easy handling when donning and doffing the protective clothing while providing an optimally adjustable restrictor effect.

[0022] A further embodiment of protective clothing according to the invention is characterized in that at least a partial area of ​​the protective clothing consists of a filter fleece, which represents a filter for the outflowing used air, wherein the partial area is preferably arranged on the rear side of the protective hood, or that the entire protective clothing consists of a cleanroom fabric or a filter fleece, wherein the filter fleece or the cleanroom fabric forms the throttle arrangement.

[0023] Further features and advantages of the invention will become apparent from the following description, which refers to the accompanying drawings.

[0024] For a better understanding of the invention, it is explained in more detail using the following figures.

[0025] They show in a highly simplified, schematic representation:

[0026] Fig. 1 shows a protective hood arrangement as an embodiment of protective clothing adapted according to the invention;

[0027] Fig. 2 is a schematic side view of a protective hood assembly with ventilation and a control arrangement according to the invention; Fig. 3 is a schematic diagram of the control arrangement of the protective hood assembly of Fig. 2;

[0028] Fig. 4 is a diagram of the pressure curve and the moving average of the pressure inside a protective hood arrangement;

[0029] Fig. 5 is a diagram of the pressure-time area between the mean value and the curve of the pressure inside the protective hood assembly;

[0030] Fig. 6 is a diagram of the pressure-time area between the mean value and the curve of the pressure inside the protective hood assembly, as well as an envelope curve with fall delay; and

[0031] Fig. 7 is a diagram of the pressure-time area between the mean value and the curve of the pressure inside the protective hood arrangement, as well as an envelope curve with fall delay and derivative addition for predictive control.

[0032] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations. The disclosures contained throughout the description can be applied mutatis mutandis to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and these positional information must be applied mutatis mutandis to the new position in the event of a change in position.

[0033] The embodiment of a protective hood assembly 1 shown in its entirety in Fig. 1 in an oblique front view as an example of protective clothing for which the control assembly 12 according to the invention (see Fig. 3) can be used, for example, which here covers the head and shoulders of the user, by way of example. The head part 2 has a preferably curved, transparent viewing panel 3 at the front. It is preferably attached, preferably pivotably, to a rigid or flexible support structure such as a preferably elastic or adjustable strap running around the user's head, a support frame for the entire protective hood assembly 1, or a helmet worn underneath the protective hood. A shoulder piece 4 is connected to the head part 2. A breathing air filter 5 for fresh air is arranged on the outside, preferably of the head part 2 of the protective hood 1.As explained later, the control arrangement 12 can also be used equally well for full-protection suits that completely envelop the user, like a jumpsuit with an integrated head section 2. Other positions for one or more breathing air filters 5 are also common here, for example, in the hip and / or back area. Preferably, a constriction 6 is provided between the head section 2 and the shoulder piece 4, or, in the case of full-body protective suits, the entire suit area adjacent to the head section 2. This constriction 6 can, for example, be implemented by an elastic and / or circumferentially adjustable collar, which represents the lower boundary of the head area 2.

[0034] As can be seen in the diagram of Fig. 2, the protective hood assembly 1 of Fig. 1 or full protective suit is typically equipped with an active air exchange system comprising at least one fan 7 surrounded by a housing with at least one exhaust opening, for example a radial fan, which draws air from the environment through the breathing air filter 5 and guides it into the interior of the protective hood assembly 1. The air flow through the fan 7 is adjusted by a control unit 8 for the fan 7. Inside the head section 2 of the protective hood assembly 1, at least one pressure sensor 9 for the air within the head section 2 is also arranged, for example integrated into the control unit 8, and if necessary connected via a signal line 10 or possibly wirelessly to a computing unit 11 within the control assembly 12, in which the pressure values ​​are processed and used to control the fan 7.The drive for the blower 7 is advantageously integrated into its housing and can represent an encapsulated unit with the blower 7.

[0035] If no external contamination is to be expected, such as when the protective hood assembly 1 is used in clean rooms whose contamination by the wearer is to be prevented, the air supply to the blower 7 can be provided through at least one opening in the protective hood assembly 1 through which air can flow essentially without hindrance. The blower 7 can be attached directly to the opening or can be connected to it via at least one air line. Advantageously, this or each opening in the protective hood 1 can be covered by a preferably permanently attached filter fleece. The protective clothing, such as the protective hood 1, preferably also has a filter for the used air. The blower 7 can also be provided with a low-voltage output for a preferably electrochemical device for generating ozone, and such a device can be arranged separately or integrated into the housing of the blower 7.

[0036] The control arrangement 12 according to the invention for the blower 7 will now be explained. The control arrangement 12 comprises the computing unit 11, preferably integrated therein as a module or circuit section, in which the signals of a sensor arrangement 13, comprising at least the pressure sensor 9, are evaluated. The pressure sensor 9 continuously or preferably at short intervals measures the pressure within the head section 2 of the protective hood arrangement 1. The sensor unit 13 can further contain at least one CO2 sensor 14. The algorithm implemented in the computing unit 11 then has a component which, when a limit value for the CO2 content within the protective hood 1 or in the head region 2 of a suit is exceeded, controls the blower 7 in order to increase the air volume flow and / or generates a warning signal.

[0037] The control arrangement 12, preferably the control unit 8 for the blower 7, can have a filter detection 15, which ensures that the blower 7 can only be put into operation after a breathing air filter 5 has been inserted and is preferably also started automatically as soon as the filter 5 is inserted and preferably also switches off automatically as soon as the filter 5 is removed.

[0038] The control arrangement 12, specifically the computing unit 11 of this arrangement, is designed, i.e. programmed with software or possibly hard-wired, to generate a control signal for the fan 7. For this purpose, this computing unit 11 is designed, via an algorithm implemented therein, to determine the user's current air requirement from the pressure curve over time and to generate a control signal to the fan 7 in order to adjust the throughput of the fan 7, preferably the speed of its fan, proportional to this air requirement of the user. Preferably, the computing unit 11 itself or the control unit 8 is designed to smooth the signal for controlling the fan 7 before it is output to the fan 7.Preferably, the combination of control unit 8 and blower 7 is designed to provide a minimum flow rate of 40 rpm and a maximum flow rate of 150 rpm for protective hoods, while for full-protection suits, a minimum flow rate of 50 rpm up to a maximum flow rate of 450 rpm is provided. Thus, the increasing CCh content of the air within the protective hood 1 or the head section 2 of a full-protection suit, which increases with increased breathing frequency, can be compensated for by increasing the air flow rate and kept below the level of an average proportion of 1 vol.% that is harmful to the user.

[0039] The blower 7 and its control unit 8 are designed in such a way that, on the one hand, they can be precisely regulated up to both limits and, on the other hand, can ensure higher loads when delivering air volumes in the upper limit range for extended periods without overload. For full-protection suits, the air volume can range from approximately 300 rpm up to a maximum air volume in the range of 500 rpm.

[0040] According to the present invention, the computing unit 11 is fundamentally designed to determine a moving average of the air pressure and to generate the signal to the control unit 8 or the blower 7 such that the throughput of the blower 7 is proportional to the difference between the moving average, which stabilizes over several breaths, and the current air pressure. Fig. 4 illustrates in diagram form the conversion of the pressure curve (curve p) to the moving average (curve p m). The area between the moving average and the pressure curve now correlates with the current air demand.

[0041] The measurement data is preferably sampled at a frequency of 3 to 100 Hz, which was found to be appropriate for the underlying task. The changes or average pressure levels during various physical activities or the transitions between activities such as sitting (area S), talking (area R), running (area L), and jogging (area J) are very clearly visible. The changes in air pressure due to the adjustment of fan 7 are compensated for using a moving average. A time window between 1 and 90 seconds was found to be optimal for calculating the moving average.

[0042] For further optimization, the algorithm implemented in the computing unit 11 is preferably expanded to generate a signal on the basis of which the fan flow rate is set proportional to the sum or integral over a specific period of time of the absolute value of the difference between the moving average and the current air pressure value. Based on the values ​​in Fig. 4, a pressure-time area (area F) corresponding to the air requirement is then obtained, as shown in the diagram in Fig. 5.

[0043] The signal from the computing unit 11 to the control unit 8 of the blower 7 is derived from the envelope curve (curve H), as shown in Fig. 6. The computing unit 11 is preferably designed by appropriate modification of the algorithm implemented therein such that the signal immediately follows increases in air demand in order to immediately and adequately cover the increased needs of the wearer of the protective clothing by increasing the air volume flow. The algorithm therefore results in a design of the computing unit 11 such that the signal to the control unit 8, represented by the envelope curve H, immediately follows an increase in the absolute value of the difference between the moving average and the current air pressure and / or the sum or integral over a certain period of the absolute value of the difference between the moving average and the current air pressure. On the other hand, changes in the opposite direction are adopted with a time delay.

[0044] Alternatively or additionally, the computing unit 11 can be designed by adapting the algorithm implemented therein such that the signal to the control unit 8 immediately follows increases in the user's air requirement in order to immediately accommodate the user's increased requirement even better by increasing the air volume flow. The algorithm thus results in a further optimized design of the computing unit 11 such that the signal to the control unit 8, represented by the envelope curve H, follows an increase in the amount of the difference between the moving average and the current air pressure and / or the sum or integral over a certain period of time of the amount of the difference between the moving average and the current air pressure to the same extent (see areas A+ in Fig. 6), and only adopts changes in the opposite direction to a fraction of the extent (see areas A- in Fig. 6).

[0045] According to a further embodiment of the invention, the computing unit

[0046] 11, an algorithm can be implemented that determines, in the form of a discrete derivative, the rate of change of the difference between the moving average and the current air pressure and / or the sum or integral, and causes a proportional change in the signal to the control unit 8 for adjusting the fan flow rate. Monitoring at intervals of 0.1 to 3 seconds and determining the average change within this period has proven optimal for this purpose.

[0047] A further improvement in the generation of the signal, which leads to optimized control of the fan 7 and is shown in Fig. 7, can be achieved by an optional embodiment of the invention, in which the computing unit is designed to determine the change in the signal for adjusting the fan flow rate proportional to the amount of the difference between the moving average and the current air pressure and / or the sum or the integral, and to effect a proportional change in the signal. The fan is already controlled to deliver a higher air volume flow whenever the air demand increases, as the algorithm makes anticipatory corrections.

[0048] According to a further embodiment of a control arrangement according to the invention, the computing unit 11 generates a signal to the control unit 8 as a proportionality factor for adjusting the throughput of the fan 7 between a predeterminable minimum throughput and a predeterminable maximum throughput, preferably as a proportionality factor between a minimum speed and a maximum speed of the fan 7.

[0049] The algorithm according to the invention and the computing unit 11, which is designed accordingly through its implementation, allow the determination of the current air requirement of the wearer of the protective hood assembly 1 or any other protective clothing equipped with the control arrangement according to the invention. With just one pressure sensor for the air pressure within the head section 2, the activity-dependent air requirement can be determined by taking into account the different characteristics of the pressure curves depending on the load or activity (sitting, talking, running, jogging).

[0050] The following strategy was chosen for the algorithm: calculation of the moving average of the pressure in the head area within the protective clothing.

[0051] Furthermore, the absolute value of the pressure-time area between the mean value and the pressure curve is determined, which is then preferably low-pass filtered.

[0052] Both the pressure-time areas above and below the mean pressure value are counted positively in order to take inspiration and exhalation into account equally, or the amount of the difference between the moving mean value and the current pressure is taken.

[0053] Furthermore, an envelope curve with a fall delay over the area is formed, preferably taking into account a derivative, preferably weighted by the difference between the pressure-time area and the envelope curve. This envelope represents the control influence on the ventilation arrangement.

[0054] If the envelope curve, which characterizes the signal for the fan's acceleration or deceleration, is lower than the pressure-time area, the change is applied at 70 to 100%. This ensures a rapid response to additional air demand. Otherwise, only 0.5% to 4% of the difference is applied, allowing the envelope to gradually approach the pressure-time area from the top. For example, if the algorithm is running at 100 Hz, the value is reduced by 1% after each execution. After 5 seconds, over 99% of the change is compensated.

[0055] This slow approach from above, i.e. the slow reduction of the air volume flow, provides safety on the one hand, since the air volume is only reduced slowly and on the other hand ensures that the fan does not constantly accelerate and brake again.

[0056] The unitless value output by the algorithm is used as a proportionality factor for the change in the air volume flow or the speed of the fan 7, although the effective fan speed must be scaled separately for each protective hood type or suit type, since the air outlet of the protective clothing and its dynamic pressure determine the size of the time-pressure area.

[0057] Instead of the fan speed, as mentioned several times above, the algorithm could also specify a mass flow, for example, with a second control loop with appropriate sensors measuring the mass flow of the air and controlling the fan accordingly. If the installation space and / or power supply allow, the air flow could also be adjusted via a controllable actuator, such as a slider or a panel.

[0058] In addition to the pressure measurement-based control defined above, a further embodiment of a control arrangement according to the invention could be equipped with a CO2 sensor 14 and a computing unit 11, which is designed to generate a signal to the control unit 8 to increase the flow rate of the blower 7 and / or a warning signal when a limit value for the CO2 concentration is exceeded, at least in the head region 2 within the protective clothing. This implements a safety function in case the rapid control via the pressure or breathing rate, which is adapted to the user's breathing air requirements, fails or is disrupted.

[0059] A preferred embodiment of a control arrangement 12 according to the invention further provides for the implementation of a safety algorithm that initiates at least one predeterminable action in the event of a non-measurable and / or non-existent pressure change, in particular, initiates a warning signal and / or switches the fan 7 to a safety mode. In safety mode, the fan preferably delivers an air flow of 80 l / min for protective hoods and 300 l / min for full-body suits.

[0060] A further advantageous embodiment of a control arrangement 12 according to the invention is characterized in that the control unit 8 is connected to or contains a detector unit 15 for the insertion of the breathing air filter 5 or a grid cover, and is designed to put the blower 7 into operation only after detection of a properly connected breathing air filter or grid cover.

[0061] Protective clothing designed particularly advantageously to solve the problem posed at the outset, which is provided with artificial ventilation by means of a blower 7 with a throughput of breathable air controllable via a control unit 8 and with a pressure sensor 9 for the air pressure at least in the head region 2 within the protective clothing, also includes - as already explained above - a computing unit 11 for determining the user's current air requirement from the pressure profile over time and generating a control signal to the blower 7. Particularly preferred is protective clothing which has a throttle arrangement for the air flowing out of the head region 2 (arrows A in Fig. 2). For this purpose, a constriction 6 is preferably provided between the head section 2 and the shoulder piece 4, or in the case of full-body protective suits enclosing the entire suit area adjoining the head section 2.This constriction 6 can be implemented, for example, by an elastic and / or circumferentially adjustable collar, which represents the lower boundary of the head region 2. This throttle arrangement amplifies the pressure changes in the head region 2 of the protective clothing to simplify the analysis and evaluation of the pressure signals.

[0062] A further embodiment of protective clothing according to the invention is characterized in that at least a partial area of ​​the protective hood 1 consists of a filter fleece, which represents a filter for the outflowing used air, wherein the partial area is preferably arranged on the rear side of the protective hood 1, or that the entire protective hood 1 consists of a cleanroom fabric or a filter fleece, wherein the filter fleece or the cleanroom fabric forms the throttle arrangement.

[0063] The exemplary embodiments show possible variants. It should be noted at this point that the invention is not limited to the specifically illustrated variants. Rather, various combinations of the individual variants and even individual features thereof are also possible. This variation possibility, based on the teaching of technical action based on the present invention, lies within the skill of the person skilled in the art. Finally, for the sake of clarity, it should be noted that some elements have been shown not to scale and / or enlarged and / or reduced in size to facilitate understanding of the structure.

Claims

P a t e n t a n s p r ü c h e 1. A control arrangement (12) for the ventilation arrangement for protective clothing (1) covering at least the user's head, with artificial ventilation by means of a blower (7) with a flow rate controllable via a control unit (8), comprising a pressure sensor (9) for the air pressure inside at least the head region (2) of the protective clothing (1), characterized by a computing unit (11) designed to determine the pressure profile over time inside at least the head region (2) of the protective clothing (1) and, therefrom, automatically determine the user's current air requirement and to generate a control signal to the blower (7) in order to adjust the flow rate of the blower depending on this air requirement, wherein the combination of control unit (8) and blower (7) is preferably designed to provide a minimum flow rate of 40 rpm and a maximum flow rate of 150 rpm for protective hoods and from 50 to 450 rpm for full-protection suits.

2. Control arrangement (12) according to claim 1, characterized in that the computing unit (11) is designed to determine a preferably moving average of the air pressure and to generate a signal to the control unit (8) in order to set the throughput of the blower (7) according to a monotonically increasing transfer function of the amount of the difference between the moving average and the current air pressure, wherein preferably the throughput of the blower (7) is set according to a monotonically increasing function of the sum or the integral over a certain period of time of the amount of the difference between the moving average and the current air pressure.

3. Control arrangement (12) according to claim 2, characterized in that the computing unit (11) is designed to generate the signal for adjusting the throughput of the blower (7) in such a way that it follows an increase in the amount of the difference between the moving average and the current air pressure and / or the sum or the integral over a certain period of time of the amount of the difference between the moving average and the current air pressure in a timely manner, and takes over changes in the opposite direction with a time delay.

4. Control arrangement (12) according to claim 2, characterized in that the computing unit (11) is designed to generate the signal for adjusting the throughput of the blower (7) in such a way that it follows an increase in the amount of the difference between the moving average and the current air pressure and / or the sum or the integral over a certain period of time of the amount of the difference between the moving average and the current air pressure to a large extent, and only takes over changes in the opposite direction to a fraction.

5. Control arrangement (12) according to claim 3 or 4, characterized in that the computing unit (11) is designed to determine the speed of change in the amount of the difference between the moving average and the current air pressure and / or the sum or the integral and to effect a change in the signal for adjusting the throughput of the fan (7) according to a monotonically increasing transfer function of this change in speed in addition to other influences on the signal.

6. Control arrangement (12) according to claim 5, characterized in that the computing unit (11) is designed to effect the change in the signal for adjusting the throughput of the blower (7) weighted according to the distance of an envelope curve over the sum or the integral over a certain period of time of the amount of the difference between the moving average and the current air pressure and the current value of this sum or the integral in addition to other influences on the signal.

7. Control arrangement (12) according to one of claims 1 to 6, characterized in that the computing unit (11) generates a signal to the control unit (8) as a monotonically increasing transfer function, preferably as a proportionality factor, for adjusting the throughput of the blower (7) between a predeterminable minimum throughput and a predeterminable maximum throughput.

8. Control arrangement (12) according to one of claims 1 to 7, characterized by a CCh sensor (14) and a control unit (8) which is designed to generate a control signal to the blower (7) when a limit value for the CCh content within the protective clothing (1) is exceeded in order to adjust the throughput of the blower (7) according to a monotonically increasing transfer function of the CO2 content and / or to generate a warning signal 9. Control arrangement (12) according to one of claims 1 to 8, characterized in that a safety algorithm is implemented therein which, in the event of a non-measurable and / or non-existent pressure change, initiates at least one predeterminable action, in particular initiates a warning signal and / or switches the fan (7) into a safety mode, wherein the fan (7) delivers a constant, predefined amount of air in the safety mode.

10. Control arrangement (12) according to one of claims 1 to 9, characterized in that the control unit (8) for the blower (7) is connected to or contains a detector unit (15) for the insertion of the breathing air filter (5) or a grid cover, and is designed to put the blower (7) into operation only after detection of a properly connected breathing air filter (5) or grid cover.

11. Protective clothing (1), in particular a protective hood or full-body protective suit covering at least the user's head, with artificial ventilation by means of a blower (7) with a throughput of breathable air controllable via a control unit (8) and a pressure sensor (9) for the air pressure at least in the head region (2) within the protective clothing (1), characterized by a computing unit (11) according to one of claims 1 to 10, which is designed to determine the user's current air requirement from the pressure curve over time and to generate a control signal to the blower (7) in order to set the throughput of the blower proportional to this air requirement.

12. Protective clothing (1) according to claim 11, characterized by a throttle arrangement (6) for the air flowing out of the head region.

13. Protective clothing (1) according to claim 12, characterized by an elastic and / or circumferentially adjustable collar as the lower boundary of the head region (2) and throttle arrangement (6).

14. Protective clothing (1) according to one of claims 11 to 13, characterized in that at least a partial area of the protective clothing (1) consists of a filter fleece (8) which represents a filter for the outflowing used air, wherein the partial area is preferably arranged on the rear side of the protective hood (1), or that the entire protective clothing (1) consists of a cleanroom fabric or a filter fleece, wherein the filter fleece or the cleanroom fabric forms the throttle arrangement.

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