DE102020129412A1 - Exhaust device with volumetric flow control - Google Patents

Abstract

The present invention relates to a fume hood device (1), in particular for laboratory areas, having a housing (3) enclosing a work space (2) with an access opening (20) for access to the work space (2) from the outside, a movable slide (4) for optionally exposing or closing the access opening (20), a controllable suction device (5) for discharging exhaust air from the working space (2) into an exhaust air system (100), several nozzle bar sections (60-63) for the directed ejection of air into the working space (2 ) for a defined flow in the working space (2) and to prevent gases from escaping from the working space (2) via the access opening (20), the nozzle bar sections (60-63) being at least partially independently controllable, sensor means (A1, A2, B1, B2, E, L1, L2, M1, M2, P, P1, P2, S1, S2, T1, T2, T3, Z) for detecting operating parameters of the extraction device (1), and a control unit (7) for regulation an exhaust air volume flow the suction device (5) and supply air volume flows of the independently controllable nozzle bar sections (60-63) depending on the operating parameters. The present invention also relates to a method for operating, in particular for controlling, an extraction device (1) according to one of the preceding claims, comprising detecting operating parameters of the extraction device (1) and regulating an exhaust air volume flow of the extraction device (5) and supply air volume flows of the respective independently adjustable nozzle bar sections (60-63) depending on the detected operating parameters.

Description

1. Fields of the Invention

The present invention relates to a fume hood device, in particular for laboratory areas, with volume flow control and a method for operating, in particular for controlling, this fume hood device.

2. Background

Extraction devices, in particular for laboratory areas, have long been known from the prior art. These are dealt with in particular in the standard DIN EN 14175 (cf. Sections 1 to 7 there). Fume hoods are designed to provide a safe work environment for scientists, engineers and medical professionals working in laboratories with hazardous/substances of concern.

A trigger device consists of a housing enclosing a working space. The working space is usually delimited by a ceiling wall, side walls and a floor wall (e.g. table top). The front area of the extraction device has an access opening, which can usually be either exposed or closed by a vertical slide. The slide in turn can have transversely displaceable horizontal slides, via which the user can also intervene in the working space, for example when the slide is closed. When closed, the slide protects the user from all hazards within the working area. If the user opens the slide, the air flow, which is generated due to a negative pressure in the working space and enters the working space via the access opening, primarily protects the user from gases and aerosols from the working space. Typically, fume hoods are attached to existing exhaust units/extraction systems to extract the air from the workspace enclosed by the fume hood. Typically, extraction devices are provided with different connections, for example to lead liquid and/or gaseous media to or into the extraction device.

Section 6 of the DIN EN 14175 standard defines the requirements for extraction devices that are to be operated with a variable air volume. Section 7 of the DIN EN 14175 standard defines additional requirements for fume hoods that are operated with increased thermal and acid loads (e.g. so-called fume hoods, Bunsen burners or other heat sources can be installed in such fume hoods).

In the prior art, in particular, extraction devices are known in which there is no targeted regulation of the volume flow and, for example, always run under full load when the window slide is open. Extraction devices are also known which vary the amount of air depending on the degree of opening of the window sash, ie the volumetric flow of air which is led out of the working space into an exhaust air system with the aid of a suction device. Such withdrawal devices are, for example, in the publications DE 44 02 541 A1 , U.S. 4,741,257 described.

Furthermore, trigger devices, for example from the publications U.S. 5,924,920A , U.S. 7,470,176 and U.S. 5,697,838 , known, which have various arrangements of actuators, by means of which a preferred cylindrical air flow can be provided within the working space.

Furthermore, extraction devices are known in the prior art which can be operated with an increased thermal load. For example, the reference discloses DE 40 40 723 A1 such a trigger device, which can in principle only be operated under heat load.

In general, it is desirable to operate an extraction device in such a way that only the amount of air required for safe work is extracted, since the operation or extraction of air from the work area involves a comparatively high energy consumption, and thus correspondingly high energy consumption causes operating costs. Typical extraction devices require as much energy as an average family home. In all known extraction devices, however, relatively large amounts of air and thus amounts of energy are consumed; This is mostly for safety reasons, even when the fume hood is in stand-by mode with little or no load, in order to anticipate and safely include any external influences.

Proceeding from this prior art, the present invention sets itself the task of specifying an extraction device that can always be operated both safely and with comparatively low energy consumption, even under changing operating conditions, and can be used over a comparatively wide control range/operating range.

These and other objects that may be mentioned or recognized by a person skilled in the art upon reading the present description are solved by the subject matter of the independent claims. Form the dependent claims the central idea of the present invention in a particularly advantageous manner.

3. Detailed Description of the Invention

According to a first aspect, an extraction device according to the invention, in particular for laboratory areas, comprises a housing enclosing a work space with an access opening for external access to the work space. Furthermore, the extraction device comprises a movable slide for selectively exposing or closing the access opening, in order to preferably allow selective access to the working space. The extraction device also includes a controllable suction device for discharging exhaust air from the work area into an exhaust air system. Furthermore, the extraction device comprises a plurality of nozzle bar sections for the directed ejection of air into the working space for a defined flow in the working space and for preventing gases from escaping from the working space via the access opening. The nozzle bar sections can be controlled or regulated at least partially independently of one another. The trigger device also has sensors or sensor means for detecting operating parameters of the trigger. Finally, the extraction device has a regulator or a control unit for regulating an exhaust air volume flow of the suction device and supply air volume flows of the nozzle bar sections that can be controlled or regulated independently in each case as a function of the operating parameters.

The extraction device according to the invention makes it possible to determine the operating state of the extraction device through its operating parameters in order to set both an exhaust air volume flow and supply air volume flows based on these operating parameters. By controlling both the supply air and the exhaust air volume flows, the extraction device can be given a defined air volume and air distribution. For example, the extraction device can be operated in a minimal operating range in the undisturbed state, since it can react actively and quickly to disturbances. In addition, the regulation can influence the quantity and the flow conditions in the extraction device 1 quickly and in a targeted manner. Consequently, the exhaust air volume flow is preferably regulated as a function of the supply air volume flows. A pull-off device is thus provided which can be operated in an optimized manner, having a high level of operational reliability with comparatively low energy consumption.

The control unit is preferably set up in such a way that it regulates the extraction device according to predefined scenarios. For this purpose, the control unit can be set up in such a way that it can assign the operating state of the exhaust device to one of several predefined degrees of severity depending on the operating parameters, and according to the assigned degree of severity regulates the exhaust air volume flow and the respective supply air volume flows.

The housing preferably has a bottom wall, a top wall and side walls which extend between the bottom wall and the top wall and together enclose the working space. A simple and versatile housing is thus provided. This preferably has a cross-section that is essentially rectangular when viewed from above, so that the extraction devices can be set up in a space-saving manner in the room and next to other extraction devices and can be combined with these if necessary.

The nozzle bar sections can be arranged around the access opening and preferably directly surrounding the access opening in order to preferably expel the air in the area of the access opening. The supply air volume flow can thus be introduced directly at the critical area of the access opening and preferably surrounding and targeted in order to increase the safety of the exhaust device overall.

Preferably, the nozzle bar sections each have a large number of nozzle openings, preferably arranged in a row. In this way, targeted jets of air can be introduced into the working space in order to form a defined supply air volume flow, for example in the form of an air wall. The nozzle openings can particularly preferably taper towards the working space in order to preferably achieve a targeted and directed blow-out without the respective air jet widening (too much). This achieves a particularly stable flow and consequently a high level of effectiveness of the supply air volume flows, which reliably shields the access opening from the outside. The nozzles forming the respective nozzle opening preferably have a run length of at least 5 mm, particularly preferably at least 10 mm, in order to achieve a particularly directed and targeted blow-out.

The nozzle bar sections can each be designed as an elongated nozzle bar. A particularly simple nozzle bar section can thus be provided. These nozzle strips can preferably have a circular cross section. In a particularly preferred embodiment, the (circular) nozzle strips can be mounted so as to be rotatable about their longitudinal axis in order to preferably select the ejection direction of the nozzles way to change or adjust by rotating about the longitudinal axis.

The nozzle bar sections may include different nozzle bar sections, such as one or more of those described below.

Thus, the nozzle bar sections can have one or more lower nozzle bar sections, preferably provided below the access opening. The lower nozzle strip section can be used to generate an air jet - a so-called support jet - which is applied to a lower housing wall delimiting the working space (e.g. the bottom wall) and thus prevents pollutants from escaping through this lower housing wall (e.g. bottom wall or . Tabletop) can prevent. If cold gases occur in the work space, they can be effectively prevented from escaping in the lower area of the work space and safely pushed backwards into the work space, where they are preferably guided to the exhaust air system by a cylindrical air flow. When warmer gases occur, a possible exit is more likely to occur in an upper area of the working space, so that in this case the supply air volume flow of the lower nozzle bar or its speed can be reduced.

Furthermore, the nozzle bar sections can have one or more lateral nozzle bar sections, preferably provided to the left and/or right of the access opening. The lateral nozzle bar sections preferably serve to shield the sides of the access opening in order to reliably prevent an escape from the working space. The lateral nozzle bar sections are preferably used to form supporting jets on the adjacent housing side walls. Preferably, these nozzle bar sections are only operated when the access opening is at least partially uncovered; e.g. when the slider is fully or partially open.

The nozzle bar sections can also have one or more upper nozzle bar sections, preferably provided above the access opening. This upper nozzle bar section should preferably prevent the exit in the upper area of the slider or the access opening; for example warm gases from the working area. The supply air volume flow of the upper nozzle strip section is preferably designed as a free jet, which stretches out like a kind of curtain in front of the access opening.

Consequently, at least one of the nozzle bar sections, preferably at least the lateral and/or the lower nozzle bar section, can be designed and arranged in such a way that this nozzle bar section can eject a directed support jet along a housing wall that delimits the working space and is adjacent to or adjacent to the nozzle bar section. Likewise, at least one of the nozzle bar sections, preferably at least the upper nozzle bar section, can be designed and arranged such that this nozzle bar section can emit a directed free jet in or into the working space in front of the access opening.

The extraction device can have several fans for feeding the nozzle bar sections with air. The fans can be controlled independently of one another, particularly preferably for controlling the supply air volume flows as a function of the operating parameters. In this case, the fans can preferably be controllable or operable continuously or stepwise. The nozzle bar sections should preferably be able to achieve blow-out speeds of 1 m/s, 1.5 m/s, 2 m/s, 2.5 m/s, 3 m/s, 3.5 m/s and/or 4 m/s; depending on the desired operating status. The fans are preferably operated with direct current; are therefore DC-operated fans. Through the use of several fans, a targeted and independent feeding of the respective nozzle bar sections can be made possible, as a result of which regulation depending on the operating parameters can be carried out in an even more differentiated manner. Each of the nozzle bar sections or each jointly controllable or controllable nozzle bar section can be assigned its own fan. For example, a separate fan can be assigned to the lower nozzle bar section, and/or a separate fan can be assigned to the upper nozzle bar section, and/or a separate fan can be assigned to the lateral nozzle bar section(s) and/or a separate fan can be assigned to the left-hand nozzle bar section be associated with a fan, and/or be associated with a separate fan for the right-hand nozzle bar section, and/or be associated with a separate fan jointly with the upper and lateral nozzle bar sections. Overall, as required, each nozzle bar section can be assigned or assignable to a fan individually or combined with others; this in a fixed assignment or variable, such as. Via valves.

The access opening is preferably provided in one of the side walls. Thus, the workspace is easily accessible for a user.

The movable slide can preferably be provided in a translatory (e.g. vertically) displaceable manner; this particularly preferred along the die Access opening having housing wall or side wall. The slide can thus be moved to save as much space as possible. In addition, the access opening can be opened evenly or in a linear manner. Also, only comparatively small disturbances are generated by the translatory movement in comparison to a pivoting door. If required, the slide should preferably enable access to the working space via the entire access opening.

The slider is preferably steplessly movable. In this way, any opening position can be set in order to always set an optimal degree of opening. Depending on the activity to be carried out, the size of the user and his hands, the required freedom of movement and the like, a differentiated degree of opening may be necessary for optimal operation.

The slider is preferably electrically movable. In this way, rapid movements of the slider can be prevented during manual actuation, which otherwise have a dynamic influence on the trigger device and can thus cause disruptions. According to a preferred embodiment, the control unit can be set up in such a way that it also regulates the slide position as a function of the operating parameters. For example, the position of the slider can be changed and, for example, closed for certain operating parameters. This is conceivable if, for example, the slider is open while no user is (any longer) present at the extraction device.

The slide can preferably have a plurality of movable slide sections in order to selectively expose the slide from the outside to the working space. For this purpose, the slide sections are preferably provided such that they can be moved or displaced in a translatory manner (e.g. horizontally or also vertically). Consequently, the slider can be exposed in sections in order to partially expose the access opening. The user can limit exposure of the access opening to what is absolutely necessary. In addition, the user can sometimes hide behind the areas that remain closed during dangerous work and thus work safely.

Possible sensor means of the extraction device are described below by way of example, which can be present in any number, arrangement, form and combination with one another.

Thus the sensor means can have at least one slider position sensor for detecting the position of the movable slider as one of the operating parameters. The slider position sensor can preferably be a cable sensor such as a cable potentiometer, a button and/or a switch such as a limit switch. It is also conceivable, when the slide is actuated by a motor, to detect the position of the same via the speed of the associated drive. A cable pull sensor is used in particular when the slider is equipped with a corresponding cable pull system in order to move it. The slide position sensor can, for example, detect the opening of the slide and determine the "open" area of the access opening. Depending on the degree of opening of the slide, exhaust air volume flow and/or supply air volume flows and preferably also the slide position itself can then be regulated.

The sensor means may include at least one section position sensor for detecting the position of the movable slide sections as one of the operating parameters. The section position sensor can preferably be an ultrasonic sensor (e.g. for scanning the open area), a light barrier sensor, a button and/or a switch such as a limit switch. The section position sensor can, for example, detect the opening of the slide sections and determine the "open" area in the slide or the access opening. Depending on the degree of opening of the slide section or slide sections, the exhaust air volume flow and/or supply air volume flows and preferably also the position of the slide section itself can then be regulated.

The sensor means can have at least one temperature sensor for detecting the temperature in the working space as one of the operating parameters. Alternatively or additionally, the sensor means can have at least one temperature sensor for detecting the temperature in the area surrounding the extraction device as one of the operating parameters. Alternatively or additionally, the sensor means can have at least two temperature sensors for detecting a temperature difference between the working space and the environment as one of the operating parameters. Alternatively or additionally, the sensor means can have at least one temperature sensor for detecting the temperature of the exhaust air in the suction device. The thermal state of the extraction device can be detected by the temperature or temperature difference detected by the temperature sensors. For example, it can be determined whether heat sources or heavy or light gases are being used in the extraction device. Depending on the detected temperature or temperature difference, exhaust air volume flow and/or supply air volume flows and preferably also the slide (section) position can then be regulated.

The use of temperature sensors makes it possible to operate the controllable or controllable suction device and the controllable or controllable nozzle bar sections independently of one another, for example as a function of the heat load in the work area or as a function of the detected temperature difference. Due to a possible temperature difference between the work space and the environment, different thermal layers can form in the work space due to the density differences at different temperatures. Furthermore, undesired flow profiles can form due to excessive temperature differences, in which case it can no longer be guaranteed that the polluted interior air will circulate safely through the supply air volume flows and the suction device will be extracted, so that pollutants can escape from the work space into the laboratory area due to the unstable flow mechanics .

Experiments have shown that the flow mechanics of an extraction device can typically become unstable at a critical temperature difference of around 4 to 6 °K and massive emissions of pollutants can occur if the temperature difference increases further. It was also found that with temperature differences of more than 10 °K, pollutants can escape even when the window is closed (e.g. through the so-called air flow openings or between the side windows above the window).

Accordingly, it is essential to prevent such critical temperature differences or to keep the temperature difference itself as small as possible. The aim is to generally operate the extraction device by appropriate control of exhaust air and supply air volume flows in a range in which the flow mechanics of the extraction device is stable, with the critical temperature difference having to be determined individually for each extraction device. As already mentioned, extraction devices typically become fluidically unstable at a temperature difference between 4 and 6 °K.

The sensor means can have at least one pressure sensor for detecting the pressure in the working space as one of the operating parameters. Alternatively or additionally, the sensor means can have at least two pressure sensors for detecting a pressure difference at least between the working space and the environment or between two different areas in the working space as one of the operating parameters. It can thus be determined whether external or internal disturbances are affecting the extraction device.

Measuring the pressure in the extraction device or in the working space can provide information as to whether the extraction device is in a stable state or in which capacity range the extraction device is currently being operated. If threshold values of the (negative) pressure are exceeded or if there are fluctuations in the (negative) pressure or the pressure difference in each case, it can be assumed that there is a dangerous condition in the extraction device or in the area surrounding it. The diagram according to 11 shows an example of a pressure profile during operation of a trigger device according to the invention over time. In an undisturbed state, the working space of the extraction device is in a stable negative pressure range. The pressure level is preferably determined from the total volume flow and the opening area of the access opening. In particular, a stable negative pressure is aimed for in order for the extraction device to function. Small short peaks (such as at seconds 3 and 6) may arise when pressures change in or around the hood (eg, in a laboratory room); for example when a door is opened. Such peaks cannot be corrected, but should preferably not be included as operating parameters for controlling the volume flows. If, for example, a person moves in front of the trigger device, this person reaches into the trigger device - i.e. its working space - or there are movements in the trigger device or its working space due to internal devices, the pressure conditions change here, for example, in a period > 1 second. This is the case, for example, at seconds 15/16, 19/20 and 23-25, indicating that there is a problem. The control unit can then, for example, immediately increase the amount of exhaust air and/or—for example, depending on the temperature—activate the supply air volume flows (ie, for example, the associated fans) in a targeted manner. Depending on the detected pressure or detected pressure difference, exhaust air volume flow and/or supply air volume flows and preferably also the slide (section) position can be regulated.

The publication DE 195 45 948 A1 entitled "Device for determining the strength of a gas volume flow" by the applicant. This publication discloses a device for determining the strength of a gas volume flow by means of a differential pressure measurement, which measures a pressure difference before and after a throttle valve in order to be able to operate the pressure sensors in their optimum accuracy range, e.g. with a control spread of at least 1 to 10.

The sensor means can have at least one movement sensor for detecting movements in the vicinity of the extraction device and preferably in front of the extraction device or the access opening as one of the operating parameters. Alternatively or additionally, the sensor means can have at least one movement sensor for detecting movements in the working space as one of the operating parameters. Depending on the detected movement or detected movement profiles, the exhaust air volume flow and/or supply air volume flows and preferably also the slide (section) position can then be regulated.

The sensor means can have at least one presence sensor for detecting the presence of objects or people in the vicinity of the extraction device and preferably in front of the extraction device or the access opening as one of the operating parameters. Alternatively or additionally, the sensor means can have at least one presence sensor for detecting the presence of objects or people in the access opening and/or in the work space as one of the operating parameters. Depending on the detected presence (possibly depending on the type, duration, position, etc. of the presence), exhaust air volume flow and/or supply air volume flows and preferably also the slide (section) position can be regulated.

The user is an important element in the operation of the extraction device, since on the one hand he must be protected from danger, but on the other hand he also creates disturbances in the system. For example, if the user stands still in front of the trigger device when the slider is closed, he has no (significant) influence on the system. However, if the user stands still in front of the trigger device with the slide (partly) open, for example, its influence is still small, but there. Movements or interventions by the user can also have a major impact on the trigger device. It can therefore be advantageous to monitor the user or his position and/or movements, for example by means of the aforementioned sensors such as movement sensors or presence sensors. For example, the user could be monitored with a camera, but this is not permitted in most cases. However, the following possibility is conceivable. Motion sensors are used to detect whether there are people in front of the extraction device. In addition, the status of the access opening is detected by a sensor, for example by detecting the position of the slider or the slider sections by means of the position sensors. By means of a negative pressure measurement, in which the internal pressure of the working space in relation to the area surrounding the extraction device (ie, for example, the laboratory room) is recorded, it can be reliably determined whether the user is handling the extraction. Here, for example, either the negative pressure can be measured or the speed of the following air can be detected via a flow sensor. As a rule, for simpler and more accurate detection, it is not the absolute value of the negative pressure that is detected, but preferably the fluctuation in the value (cf. again the previously described 11 ). Short peaks indicate temporary disturbances, for example. These disturbances can come from movements of the user. Short peaks cannot necessarily be corrected. However, they increase the hazard level of the extraction device and thus preferably lead to a higher volume of exhaust air. If the peaks persist, the hazard level is increased and the amount of exhaust air is further increased or even maximized.

The sensor means can have at least one pollutant sensor for detecting pollutants in the working space as one of the operating parameters. As an alternative or in addition, the sensor means can have at least two pollutant sensors for detecting a pollutant difference between the working space and the environment as one of the operating parameters. The latter can be important since diffusion processes can occur due to the difference in pollutants. Depending on the detected pollutant or detected pollutant difference (possibly depending on the type, concentration, residence time, etc. of the pollutant) exhaust air volume flow and / or supply air volume flows and preferably also the slider (section) position can be regulated.

The sensor means can have at least one sensor for detecting the volume of exhaust air from the suction device as one of the operating parameters. As an alternative or in addition, the sensor means can have at least one sensor for detecting the volume flow conducted from the working space into the exhaust air system (ie the exhaust air volume flow) as one of the operating parameters. Depending on the detected amount of exhaust air or volume flow, exhaust air volume flow and/or supply air volume flows and preferably also the slide (section) position can then be regulated. The sensor for detecting the amount of exhaust air or the volume flow can preferably be one or more pressure sensors for detecting a pressure difference in the exhaust line (preferably in the extraction device or between the extraction device and the exhaust air system). The sensor for detecting the amount of exhaust air or the volume flow can also be a setting sensor for detecting a setting position of a motor-driven actuator, such as a control flap, for controlling the suction device. The detection of the exhaust air volume flow is therefore preferably carried out via a pressure difference measurement on the exhaust line, while the control example wise via a high-speed motorized control flap.

The sensor means can have at least one intake air quantity detection sensor, preferably for each nozzle bar section that can be controlled or regulated independently of one another, for detecting the intake air quantity via the respective (individual and/or groups of) nozzle bar section(s) as one of the operating parameters. For example, when using DC fans to feed the nozzle bar sections, the speed of these fans can be detected by the intake air quantity detection sensor and the intake air volume flow can thus be determined.

The sensor means can have at least one energy detection sensor for detecting the amount of energy currently being consumed by the extraction device. For example, the power consumption of the extraction device can be recorded via sockets, as a result of which the amount of energy consumed in the extraction device can be determined. A comparable principle can be applied by determining the amount of gas currently consumed by gas consumers using a flow meter.

The extraction device is preferably designed in such a way that the amount of exhaust air and/or the volume flow conducted from the work space into the exhaust air system is between 100 and 1500 m ³ /h/m, preferably between 100 and 550 m ³ /h/m or between 200 and 850 m3/h/lfm or between 300 and 1500 m3/h/ ^lfm . Such dimensioning makes it possible to operate the extraction device in a wide range, for example between about 100 and 1500 m ³ /h/m, so that the extraction device according to the invention can be operated for all specified control ranges according to DIN EN 14175 (DN 200 for a control range of 100 to 550 m ³ /h/lfm for small fume cupboards DN 250 for a control range of 200 to 850 m ³ /h/lfm for medium fume cupboards DN 315 for a control range of 300 to 1500 m ³ /h/lfm for large deductions). Fume hoods are usually made with outside widths between 1.2 and 2.1 meters. The amount of exhaust air from fume cupboards is often shown in m3/h/lfm (i.e. cubic meters per hour and running meter) in order to be able to compare different fume cupboards. The unit running meter is then displayed as the outer width of the fume cupboard in meters. At 400 m3/h/lfm, a fume hood with an external width of 1.2 meters requires an exhaust air volume of about 480 m ³ /h, while a fume hood with an external width of 2.1 meters requires an exhaust air volume of about 820 m ³ /h.

The suction device can be arranged above the working space, preferably on an upper housing wall or the ceiling wall. In this way, a preferred air circulation can be generated. In addition, the exhaust air will take place at a location that is in conflict with a work surface. Likewise, exhaust air systems are usually provided on the ceiling side, so that the connection of the extraction device is simplified. The housing wall assigned to the suction device or the top wall can also preferably be designed for the most part as a perforated wall plate in order to fluidically connect the working space with the suction device. In this way, the air can be discharged directly from the upper area of the working area.

The slide can completely close the access opening in a rest position, partially uncover the access opening in a working or engaged position, preferably with a height of about 450 mm, and in an open position maximally or completely uncover the access opening, preferably with a height of about 900 mm. The extraction device can preferably be arranged on a table construction in such a way that the (vertically) movable slide is positioned with its lower edge at a height of about 900 mm in the closed state (i.e. the table construction essentially has a height of about 900 mm). Typically, the slider also has a height of about 900 mm, so that when the extraction device is arranged on the table construction, the slider is arranged at a height of between 900 mm and about 1800 mm. In the typical working or intervention position described above, the lower edge of the window slider is arranged at a height of approximately 1350 mm. In addition to working in the work area, the fully open state of the slider is also required for maintenance.

The extraction device can also have post-flow openings, so that air can flow into the working space even when the slider is completely closed. Such post-flow openings are typically provided above and below the slide at the front of the extraction device. Such afterflow openings are particularly advantageous for so-called night-time operation, in which the slide is completely closed, in order to be able to provide sufficient air exchange or sufficient suction even in this operating state.

The triggering device can have input means, such as a touch display, switch, regulator, lever, button, and/or output means, such as display means, display, indicator lamps. This makes it possible to display the current operating status of the trigger device to the operator, or the operator can switch the operating status of the trigger device by means of corresponding operating elements, for example from a regular operation to night operation. Furthermore, it is advantageous if the extraction device includes optical and/or acoustic alarm means. This makes it possible to warn the laboratory staff if, for example, a critical temperature is reached in the work space or the flow within the work space becomes unstable and there is a risk of pollutants escaping from the work space into the laboratory space. There is also the possibility that the user flushes the extraction device manually (ie essentially the entire work space is emptied by the extraction device by means of laminar flow).

According to a further aspect, the present invention also relates to a method for operating an extraction device according to the invention. First of all, the operating parameters of the extraction device are recorded. Then, an exhaust air volume flow of the suction device and supply air volume flows of the nozzle bar sections that can be controlled or regulated independently in each case are regulated as a function of the operating parameters detected. The two aforementioned steps can be repeated as often as you like; for example continuously while the extraction device is in operation.

For example, the following are recorded as the operating parameters: the position of the movable slide (e.g. by means of the slide position sensor), the position of the movable slide sections (e.g. by means of the section position sensor), the temperature in the working space (e.g. by means of the temperature sensor) , a temperature difference between the work space and the environment (e.g. using the temperature sensors), the temperature of the exhaust air in the suction device (e.g. using the temperature sensor), the pressure in the work space (e.g. using the pressure sensor), a pressure difference at least between the work space and the environment (e.g. by means of the pressure sensors), a pressure difference at least between two different areas in the working space (e.g. by means of the pressure sensors), movements in the vicinity of the extraction device and preferably in front of the extraction device or the access opening (e.g. by means of the movement sensor), Movements in the workspace (e.g. by means of the motion sensor), the presence of objects or people in the vicinity of the extraction device and preferably in front of the extraction device or the access opening (e.g. using the presence sensor), the presence of objects or people in the access opening and/or in the workspace (e.g. using the presence sensor), pollutants in the workspace (e.g. using the pollutant sensor), a difference in pollutants between the workspace and the environment (e.g. by means of the pollutant sensors), the exhaust air volume of the extraction device (e.g. by means of the sensor for recording the exhaust air volume of the extraction device), the volume flow led from the work space into the exhaust air system (e.g. by means of the sensor for recording the volume flow led from the work space into the exhaust air system) , the intake air quantity(s) via the respective nozzle bar sections (e.g. by means of the intake air quantity detection sensor) and the amount of energy currently consumed by the extraction device (e.g. by means of the energy detection sensor). Depending on the extraction device, duration and type of experiments to be carried out, the materials handled, and much more, different operating parameters and combinations thereof may be required, which can therefore also be combined in any way in order to carry out a desired process. For example, a targeted combination of sensor means (e.g. presence and/or movement sensors and pressure sensors) can be used to precisely determine, for example, interventions by users in the working space of the extraction device.

The control unit is preferably set up to assign the operating state of the exhaust device to one of several predefined degrees of severity depending on the operating parameters, and to regulate the exhaust air volume flow and the respective supply air volume flows according to the assigned degree of severity.

For this purpose, the operating parameters can particularly preferably be recorded continuously or regularly. The assignment and/or the regulation can particularly preferably also be carried out continuously or regularly. By means of the assignment to predefined degrees of severity, different control scenarios can be predetermined, which are implemented when corresponding operating parameters are present. The control can thus be simplified overall and any computer capacities can be used efficiently and thus in a way that conserves resources and energy.

The degrees of severity preferably include at least one low degree of severity and one high degree of severity, so that at least two control scenarios can be distinguished and the device (ie its exhaust air and supply air volume flows) can be controlled accordingly. Preferably, the severities further include a minimum severity, and/or a very low severity, and/or a medium severity, and/or a very high severity, and/or a maximum severity. Other degrees of severity can also be provided. Thus, degrees of severity with different and preferably increasing severity can be predefined the, so that the device can be regulated in any differentiated manner.

By way of example, the very low (or low) degree of severity can be present in an operating condition in which the slide and, if present, the slide sections are closed, the working space is preferably isothermal, no person or object is detected in the vicinity of the trigger device, none There are pressure fluctuations in the work area, no energy consumption is recorded.

• o Abluftvolumenstrom: minium
• o Zuluftvolumenstrom unten: minimum
• o Zuluftvolumenstrom oben und seitlich: aus

If the severity is very low, the control unit can preferably carry out the following control:

• o Extract air volume flow: minimum
• o Supply airflow below: minimum
• o Supply air volume flow top and side: off

For example, the low degree of severity can be present in an operating state in which the slide and, if present, the slide sections are closed, an isothermal state preferably prevails in the working space, no person or object is detected in the vicinity of the extraction device, there are no pressure fluctuations in the working space, low energy consumption is detected.

• o Abluftvolumenstrom: gering
• o Zuluftvolumenstrom unten: minimum
• o Zuluftvolumenstrom oben und seitlich: aus

If the severity is low, the control unit can preferably carry out the following control:

• o Extract air volume flow: low
• o Supply airflow below: minimum
• o Supply air volume flow top and side: off

For example, the medium degree of severity can be present in an operating state in which the slide and, if present, the slide sections are closed, an isothermal state preferably prevails in the working space, no person or object is detected in the vicinity of the extraction device, there are no pressure fluctuations in the working space, an increased or high energy consumption is detected.

• o Abluftvolumenstrom: mittel
• o Zuluftvolumenstrom unten: minimum
• o Zuluftvolumenstrom oben und seitlich: mittel

If the degree of severity is medium, the control unit can preferably carry out the following control:

• o Extract air volume flow: medium
• o Supply airflow below: minimum
• o Supply airflow top and side: medium

For example, the high degree of severity can be present in an operating state in which the slide and, if present, the slide sections are at least partially open, the temperature in the working space is preferably elevated, a person is detected in the vicinity of the extraction device, there are low pressure fluctuations in the working space, low energy consumption is recorded.

• o Abluftvolumenstrom: höher
• o Zuluftvolumenstrom unten: hoch
• o Zuluftvolumenstrom oben und seitlich: hoch

In the event of the high degree of severity, the control unit can preferably carry out the following control:

• o Extract air volume flow: higher
• o Supply airflow below: high
• o Supply air volume flow top and side: high

For example, the very high degree of severity can be present in an operating state in which the slide and, if present, the slide sections are at least partially open, the temperature in the working space is preferably elevated, a person is detected in the vicinity of the extraction device, there are low pressure fluctuations in the working space , an increased or high energy consumption is detected.

• o Abluftvolumenstrom: hoch
• o Zuluftvolumenstrom unten: mittel
• o Zuluftvolumenstrom oben und seitlich: maximal

If the degree of severity is very high, the control unit can preferably carry out the following control:

• o Extract air volume flow: high
• o Bottom supply airflow: medium
• o Supply air volume flow top and side: maximum

For example, the maximum degree of severity can be present in an operating state in which the slide and, if present, the slide sections are at least partially open, the temperature in the working space is preferably elevated, a person is detected in the vicinity of the extraction device, increased pressure fluctuations are present in the working space, an increased or high energy consumption is detected.

• o Abluftvolumenstrom: maximal
• o Zuluftvolumenstrom unten: hoch
• o Zuluftvolumenstrom oben und seitlich: maximal.

If the maximum severity is present, the control unit can preferably carry out the following control:

• o Extract air volume flow: maximum
• o Supply airflow below: high
• o Supply air volume flow top and side: maximum.

character list

• 1 eine Vorderansicht einer bevorzugten Ausführungsform einer erfindungsgemäßen Abzugsvorrichtung;
• 2 eine schematische Seitenansicht im Querschnitt der Abzugsvorrichtung gemäß 1;
• 3 eine schematische Seitenansicht im Querschnitt der Abzugsvorrichtung gemäß 1 gemäß einem ersten Betriebsszenario (Szenario 1);
• 4 eine schematische Seitenansicht im Querschnitt der Abzugsvorrichtung gemäß 1 gemäß einem zweiten Betriebsszenario (Szenario II);
• 5 eine schematische Seitenansicht im Querschnitt der Abzugsvorrichtung gemäß 1 gemäß einem dritten Betriebsszenario (Szenario III);
• 6 eine schematische Seitenansicht im Querschnitt der Abzugsvorrichtung gemäß 1 gemäß einem vierten Betriebsszenario (Szenario IV);
• 7 eine schematische Seitenansicht im Querschnitt der Abzugsvorrichtung gemäß 1 gemäß einem fünften Betriebsszenario (Szenario V);
• 8 eine schematische Seitenansicht im Querschnitt der Abzugsvorrichtung gemäß 1 gemäß einem sechsten Betriebsszenario (Szenario VI);
• 9 eine graphische Darstellung der Zuluftvolumenströme über die obere, seitlichen und untere Düsenleistenabschnitte der erfindungsgemäßen Abzugsvorrichtung gemäß der Szenarien I-VI;
• 10 eine graphische Darstellung der Abluftvolumenströme über die Absaugeinrichtung der erfindungsgemäßen Abzugsvorrichtung gemäß der Szenarien I-VI;
• 11 eine graphische Darstellung einer möglichen Druckdifferenzmessung der erfindungsgemäßen Abzugsvorrichtung über der Zeit.
• 12 ein Blockschaltbild der Regelung der Abzugsvorrichtung gemäß 1.

Further configurations, features and advantages of the present invention are based on FIG of the figures of the accompanying drawings are described below. Show it:

• 1 a front view of a preferred embodiment of a trigger device according to the invention;
• 2 a schematic side view in cross section of the extraction device according to FIG 1 ;
• 3 a schematic side view in cross section of the extraction device according to FIG 1 according to a first operational scenario (Scenario 1);
• 4 a schematic side view in cross section of the extraction device according to FIG 1 according to a second operating scenario (Scenario II);
• 5 a schematic side view in cross section of the extraction device according to FIG 1 according to a third operating scenario (Scenario III);
• 6 a schematic side view in cross section of the extraction device according to FIG 1 according to a fourth operational scenario (Scenario IV);
• 7 a schematic side view in cross section of the extraction device according to FIG 1 according to a fifth operating scenario (Scenario V);
• 8th a schematic side view in cross section of the extraction device according to FIG 1 according to a sixth operating scenario (Scenario VI);
• 9 a graphical representation of the supply air volume flows over the upper, lateral and lower nozzle bar sections of the extraction device according to the invention according to scenarios I-VI;
• 10 a graphic representation of the exhaust air volume flows via the suction device of the extraction device according to the invention according to scenarios I-VI;
• 11 a graphical representation of a possible pressure difference measurement of the extraction device according to the invention over time.
• 12 a block diagram of the control of the extraction device according to 1 .

5. Description of a preferred embodiment

the 1 until 8th show different representations and operating states of a withdrawal device 1 according to the present invention. The extraction device 1 can preferably be an extraction device for the laboratory area; preferably in accordance with the DIN EN 14175 standard (cf. Sections 1 to 7 there).

The extraction device 1 has a housing 3 enclosing a working space 2 with an access opening 20 for accessing the working space 2 from the outside. The housing 3 here preferably has a bottom wall (here in the form of a table top) 30, a top wall 31 and side walls 32-35 which extend between the bottom wall 30 and the top wall 31 and which together enclose the working space 2. The access opening 20 is preferably in one of the side walls 32-35 - here preferably in the front side wall 32 - provided.

The extraction device 1 also has a movable slide 4 for selectively exposing or closing the access opening 20 . The movable slide 4 is preferably provided in a translationally displaceable manner. The slider 4 is particularly preferably provided so that it can be moved vertically by means of a translational up and down movement for selectively exposing and closing the access opening 20 . The slide 4 preferably moves along the housing wall or side wall 32 that has the access opening 20.

The slider 4 is preferably steplessly movable. The slide can be provided so that it can be moved by means of a cable pull 40 . The slider 4 can be provided to be electrically movable; this, for example, by means of an electric motor M1.

The slide 4 can also have a plurality of movable slide sections 41-43 in order to selectively expose the slide 4 from the outside to the working space 2. For this purpose, the slide sections 41-43 are preferably also provided such that they can be moved in a translatory manner. The translational movement of the slide sections 41-43 is preferably horizontal here. In the embodiment of 1 For example, the two left slide sections 41, 42 can each be pushed to the right behind the respective adjacent slide section 42, 43 in order to selectively expose a vertical surface of the slide 4, which corresponds to approximately one third of the width of the slide 4.

The slider 4 can preferably be in a rest position (cf. 1-5 ) completely closing or covering the access opening 20, in a working or engaging position partially uncovering the access opening, preferably with a height of about 450 mm, and in an open position (cf. 6-8 ) maximally or completely uncover the access opening, preferably with a height of about 900 mm. The extraction device can preferably be arranged on a table construction 5 in such a way that the (vertically) movable slide 4 with its bottom edge 44 positioned at a height of about 900mm when closed (ie the table structure 5 generally has a height of about 900mm). Typically, the slider 4 also has a height of about 900 mm, so that when the extraction device 1 is arranged on the table construction 10, the slider 4 is arranged at a height of between 900 mm and about 1800 mm. In the typical working or intervention position described above, the lower edge of the window slider is arranged at a height of approximately 1350 mm.

The extraction device can also preferably have post-flow openings 21, 22, so that air can flow into the working space even when the slide 4 is completely closed.

The extraction device 1 also has a controllable suction device 5 for discharging exhaust air from the working space 2 into an exhaust air system 100. The suction device 5 is preferably arranged above the working space 2 here. Like the one in particular 2-8 can be seen, the suction device 5 is preferably provided on an upper housing wall or the top wall 31 . The suction device is preferably provided in a rear region of the extraction device 1 and is therefore preferably spaced apart from the access opening 20 . The housing wall assigned to the suction device 5 or the top wall 31 is preferably designed for the most part as a perforated wall plate 36 or has such a wall plate in order to fluidically connect the working space 2 to the suction device 5 . Thus, a planar suction can preferably take place in the upper area of the extraction device 1 . The perforated wall plate 36 is provided in such a way that a mixing chamber 37 is provided on the side facing away from the working space 20 and facing the suction device 5 , ie preferably above the working space 2 and the perforated wall plate 36 . From the mixing chamber 37, the extraction device 1 can be connected to the exhaust air system 100, for example via a volume flow controller 50 of the suction device 5, which is preferably also controllable. The volume flow controller 50 can be designed here as a control valve. This can be continuously adjustable. Likewise, the adjustable flap 50 is preferably operated by a motor by means of an electric motor MS. The suction device 5 or the exhaust air system 100 can also have a controllable exhaust air motor MA as a volume flow controller for controlling the exhaust air volume flow.

The extraction device 1 is preferably designed in such a way that the amount of exhaust air and/or the volume flow guided from the working space 2 into the exhaust air system 100 can be between 100 and 1500 m ³ /h/lfm, preferably between 100 and 550 m ³ /h/lfm or between 200 and 850 m3/h/lfm or between 300 and 1500 m3/h/ ^lfm .

The extraction device 1 also has a plurality of nozzle strip sections 60-63 for the directed ejection of air into the working space 2 for a defined flow in the working space 2 and to prevent gases from escaping from the working space 2 via the access opening 20 .

The nozzle bar sections 60-63 are preferably arranged around the access opening 20 and preferably directly surrounding the access opening 20 in order to preferably expel the air in the region of the access opening 20. A particularly effective flow profile can thus be achieved and gases escaping from the access opening 20 can be avoided.

At least one of the nozzle bar sections 60-63, preferably at least the or one of the side nozzle bar sections 62, 63 and/or the lower nozzle bar section 60, can be designed and arranged in such a way that this nozzle bar section 60-63 has a directed support jet along the working space 2 limiting and the nozzle bar section 60-63 adjacent housing wall 30, 34, 35 can eject. In the illustrated embodiment, for example, the lower nozzle bar section 60 is designed accordingly and thus generates a support jet along the floor wall or tabletop 30. This preferably leads to a stable flow on the tabletop 30, accelerates the air and thus pushes any heavy gases that may be present out of the workspace 2 directly to and into the suction device 5.

At least one of the nozzle bar sections 60-63, preferably at least the upper nozzle bar section 61, can be designed and arranged such that this nozzle bar section 60-63 can eject a directed free jet into and into the working space 2 in front of the access opening 2. This free jet can preferably stretch out like a kind of curtain in front of the access opening 20 and thus prevent any gases from escaping from the working space 2 via the access opening and in particular in an upper region thereof.

The nozzle bar sections 60-63 preferably each have a large number of nozzle openings 64, preferably arranged in a row. The nozzle openings 64 particularly preferably taper towards the working space 2 in order to achieve a targeted and directed blow-out without widening. Because due to the constriction inside the nozzle opening 64 or the nozzle forming it, a stable flow is generated which hardly widens and thus preferably shields the access opening 20 securely. This is particularly preferred if the nozzle openings 64 have a running length of at least 5 mm, preferably at least 10 mm. The individual nozzles can preferably be provided in such a way that they can be exchanged individually in order to optimally provide the flow profile of the individual nozzles depending on the application or extraction device 1 and the desired application and the like.

The nozzle bar sections 60-63 are preferably each configured as an elongate nozzle bar (particularly preferably extending in a straight line). The nozzle bar sections 60-63 preferably have a circular cross-section. In this case, the respective nozzle bar sections 60-63 can be mounted so as to be rotatable about their longitudinal axis, so that the ejection direction of the respective nozzle bar section 60-63 can be optionally set or changed.

Different nozzle bar sections can be provided. Thus, a lower nozzle bar section 60, preferably provided below the access opening 20, can be provided. Likewise, an upper nozzle bar section 61, preferably provided above the access opening 20, can be provided. In addition, one lateral nozzle bar section, preferably also several lateral nozzle bar sections 62, 63, can be provided; these are then particularly preferably provided on the left and/or right of the access opening 20 . In the illustrated embodiment, the lateral nozzle bar sections 62, 63 are provided on both sides of the access opening 20.

A particular aspect of the extraction device 1 according to the invention is that the nozzle bar sections 60-63 can be controlled or regulated at least partially independently of one another. Each nozzle bar section 60-63 can therefore be controlled or regulated independently of the other ones. It is also conceivable that groups of nozzle bar sections 60-63 can also be controlled or regulated together but independently of the other (groups of) nozzle bar sections 60-63 permanently or optionally. For example, the upper and lateral nozzle bar sections 61-63 can be controlled or regulated together at least temporarily.

The extraction device 1 can also have several fans V ₁ -V ₄ for charging the nozzle bar sections 60-63 with air. The fans V ₁ -V ₄ are preferably DC (direct current) operated fans V ₁ -V ₄ . The fans V ₁ -V ₄ can preferably be controlled or regulated independently of one another, this particularly preferably steplessly or stepwise. The fans V ₁ -V ₄ can be used to preferably blow out velocities of the nozzle bar sections 60-63 (i.e. via their nozzle openings 64) of, for example, optionally 1 m/s, 1.5 m/s, 2 m/s, 2.5 m/s, 3 m/s , 3.5m/s and/or 4m/s. Higher and lower and any desired blow-out speeds in between are also conceivable.

Each of the nozzle bar sections 60-63 or the jointly controllable or controllable nozzle bar sections 60-63 can preferably be assigned its own fan (V1-V4). For example, a separate fan V1 can be assigned to the lower nozzle strip section 60 . A separate fan V2 can also be assigned to the upper nozzle bar section 61 . The lateral nozzle strip sections 62, 63 can also be assigned their own fan. Likewise, the left-hand nozzle bar section 62 can be assigned its own fan V3. A dedicated fan V4 can also be assigned to the right-hand nozzle bar section 63 . Furthermore, the upper and lateral nozzle bar sections 61-63 can also be assigned their own fan.

The trigger device 1 also has sensor means for detecting operating parameters of the trigger device 1 . The sensor means can have at least one or more of the following sensor means in any combination and number.

Thus the sensor means may comprise one or more slide position sensors M1 for detecting the position of the movable slide 4 as one of the operating parameters. The slider position sensor M1 can preferably be a cable-pull sensor such as a cable-pull potentiometer, a button and/or a switch such as a limit switch.

Likewise, the sensor means may include one or more section position sensors P for detecting the position of the movable slide sections 41-42 as one of the operating parameters. The section position sensor P can preferably be an ultrasonic sensor, a light barrier sensor, a button and/or a switch such as a limit switch.

Furthermore, the sensor means can have one or more temperature sensors T1 for detecting the temperature in the working space 2 as one of the operating parameters.

The sensor means can also have one or more temperature sensors T3 for detecting the temperature in the environment U of the extraction device 1 as one of the operating parameters. The sensor means can also have two or more Tem have temperature sensors T1, T3 for detecting a temperature difference between the working space 2 and the environment U as one of the operating parameters. The sensor means can also have one or more temperature sensors T2 for detecting the temperature of the exhaust air in the suction device 5 .

In addition, the sensor means can have one or more pressure sensors P1 for detecting the pressure in the working chamber 2 as one of the operating parameters. The sensor means can also have two or more pressure sensors P1, P2 for detecting a pressure difference at least between the working space 2 and the environment U or between two different areas in the working space 2 as one of the operating parameters.

Likewise, the sensor means can have one or more movement sensors B1 for detecting movements in the environment U of the extraction device 1 and preferably in front of the extraction device 1 or the access opening 20 as one of the operating parameters. The sensor means can also have one or more movement sensors B2 for detecting movements in the working space 2 as one of the operating parameters.

The sensor means can also have one or more presence sensors A1 for detecting the presence of objects or persons in the environment U of the extraction device 1 and preferably in front of the extraction device 1 or the access opening 20 as one of the operating parameters. The sensor means can also have one or more presence sensors A2 for detecting the presence of objects or people in the access opening 20 and/or in the work space 2 as one of the operating parameters.

The use of ultrasonic sensors, infrared sensors, PIR sensors (pyroelectric sensors), cameras, and the like is conceivable for motion sensors B1, B2 and presence sensors A1, A2.

The sensor means can also have one or more pollutant sensors S1 for detecting pollutants in the working space 2 as one of the operating parameters. The sensor means can also have two or more pollutant sensors S1, S2 for detecting a pollutant difference between the working space 2 and the environment U as one of the operating parameters.

The sensor means can also have one or more sensors L1, L2 for detecting the volume of exhaust air from the suction device 5 as one of the operating parameters. The sensor means can also have one or more sensors M2 for detecting the volume flow conducted from the working space 2 into the exhaust air system 100 as one of the operating parameters. The sensor L1, L2 for detecting the amount of exhaust air or the sensor M2 for detecting the volume flow can preferably be a pressure sensor L1, L2 for detecting a pressure difference in the exhaust air line and/or a positioning sensor M2 for detecting a positioning position of the motor-operated adjustable flap 50 for controlling the suction device 5 be.

The sensor means can also have one or more intake air quantity detection sensors Z1, Z2, Z3, preferably for each nozzle bar section 60-63 that can be controlled or regulated independently of one another, for detecting the quantity of intake air via the respective nozzle bar sections 60-63 (or groups thereof) as one of the operating parameters. For example, when using DC fans V ₁ -V ₄ to feed the nozzle bar sections 60-63, the speed of these fans V ₁ -V ₄ can be detected by the intake air quantity detection sensor Z1, Z2, Z3 and thus the intake air volume flow can be determined.

The sensor means can also have one or more energy detection sensors E1, E2 for detecting the amount of energy currently being consumed by the extraction device 2. In this case, for example, the power consumption of the extraction device 1 via sockets can be detected by means of an energy detection sensor E1, as a result of which the amount of energy consumed in the extraction device 1 can be determined. A comparable principle can be applied by determining the amount of gas currently consumed by gas consumers via flow meter E2.

The extraction device 1 also has a control unit 7 for regulating an exhaust air volume flow of the suction device 5 and supply air volume flows of the nozzle bar sections 60-63 that can be controlled or regulated independently, depending on the operating parameters.

The trigger device 1 can have any input means 8, such as a touch display, switch, controller, lever, button, etc., and/or output means 9, such as display means, displays, indicator lamps, etc. The extraction device 1 can also have optical and/or acoustic alarm means

12 shows an example of a block diagram of the control of the extraction device 1 according to the invention. It can be seen that the operating parameters, for example, the signals of the three temperature sensors T1-T3, the slider position sensor M1, the section position sensor P, the movement sensors B1, B2, the presence sensors A1, A2, the pollutant sensors S1, S2, the sensor M2 for detecting the volume flow conducted from the working space 2 into the exhaust air system 100, the intake air quantity detection sensor Z1, Z2, Z3, the energy detection sensor E1, E2, the pressure difference Δp of the pressure sensors P1 and P2, and the pressure difference Δl of the pressure sensors L1 and L2. On the basis of and depending on the operating parameters obtained, the control unit 7 controls or regulates the exhaust air volume flow of the suction device 5 (e.g. via the exhaust air motor MA or the adjusting cap 50, and the supply air volume flows of the independently controllable or adjustable nozzle bar sections 60-63 (e.g. via the speed of the fans V1-V4). For control purposes, the signals (e.g. command values), for example from the fans V ₁ -V ₄ and the exhaust air motor MA or the damper motor MS, are fed back to the control unit 7. In addition, the user can make entries 1 in the The system can be made, for example via the input means 8. The system can also output outputs O, for example via the output means 9.

A method for operating—in particular for controlling—the extraction device 1 according to the invention is described below.

In a first step, operating parameters of the extraction device 1 are recorded.

The following parameters can be recorded as the operating parameters, for example: the position of the movable slide 4 (e.g. by means of the slide position sensor M1), the position of the movable slide sections 41-43 (e.g. by means of the section position sensor P), the temperature in Working space 2 (e.g. using the first temperature sensor T1), a temperature difference between working space 2 and the environment U (e.g. using the first and third temperature sensors T1, T3), the temperature of the exhaust air in the suction device 5 (e.g. using the second temperature sensor T2), the pressure in the working space 2 (e.g. by means of the first pressure sensor P1), a pressure difference at least between the working space 2 and the environment U (e.g. by means of the first and second pressure sensors P1, P2), a pressure difference at least between two different ones Areas in the working space 2 (e.g. by means of the first pressure sensor P1 and a further pressure sensor, not shown), moving ments in the vicinity U of the trigger device 1 and preferably in front of the trigger device 1 or the access opening 20 (e.g. by means of the first motion sensor B1), movements in the working space 2 (e.g. by means of the second motion sensor B2), the presence of objects or people in the vicinity U of the extraction device 1 and preferably in front of the extraction device 1 or the access opening 20 (e.g. by means of the first presence sensor A1), the presence of objects or people in the access opening 20 and/or in the working space 2 (e.g. using the second presence sensor A2), pollutants in the working space 2 (e.g. using the first pollutant sensor S1), a pollutant difference between the Working space 2 and the environment U (e.g. by means of the first and second pollutant sensors S1, S2), the amount of exhaust air from the extraction device 5 (e.g. by means of the first and second sensors L1, L2 for detecting the amount of exhaust air from the extraction device 5), the 2 volume flow conducted into the exhaust air system 100 (e.g. by means of the sensor M2 for detecting the flow from the work space into the exhaust volume flow guided by the air system), the supply air volume(s) via the respective nozzle bar sections 60-63 (e.g. by means of the intake air quantity detection sensor Z1, Z2, Z3), and the amount of energy currently consumed by the extraction device 1 (e.g. by means of the energy detection sensor E1, E2). Depending on the extraction device 1, duration and type of experiments to be carried out, materials used, and much more, different operating parameters and combinations thereof may be required, which can therefore also be combined in any way in order to carry out a desired method.

In a second step, the exhaust air volume flow of the extraction device 5 (e.g. by controlling the servomotor MS for setting the adjustable flap 50 or controlling its opening angle/degree of opening; possibly also by (continuously) controlling the exhaust air system 100) and the supply air volume flows of the respective independently Controllable or controllable nozzle bar sections 60-63 (e.g. by controlling the fans V ₁ -V ₄ or controlling their speed) as a function of the detected operating parameters.

In a preferred embodiment, the control unit 7 is set up in such a way that, in an optional step, it assigns the operating state of the extractor device 1 to one of several predefined degrees of severity, depending on the operating parameters, and regulates the exhaust air volume flow and the respective supply air volume flows according to the assigned degree of severity. In this case, the operating parameters can preferably be recorded continuously or regularly. Likewise, the assignment and/or the regulation can preferably also be carried out continuously or regularly. A predefined operating scenario can therefore be determined by means of the sensor means and the operating parameters determined in this way, on the basis of which the exhaust and intake air volume flows are regulated. In this way, the quantities of exhaust air and the quantities of incoming air can be regulated in a particularly differentiated and reliable manner, and therefore preferably also the air flow in the extraction device 1, ie in particular in the working space 2, can be controlled or regulated.

The severities may include at least a low severity and a high severity, but preferably include other severities, preferably of increasing/decreasing severity. For example, the severity levels may further preferably include a minimum severity level and/or a very low severity level and/or a medium severity level and/or a very high severity level and/or a maximum severity level.

The degrees of severity are described below with an exemplary classification into a total of six degrees of severity, which here include a very low, low, medium, high, very high and maximum degree of severity.

The very low degree of severity is present here, for example, in an operating state in which the slide 4 and, if present, the slide sections 41-43 are closed, there is preferably an isothermal state in the working space 2, no person or object in the area U of the extraction device 1 are recorded, there are no pressure fluctuations in the working space 2, and no energy consumption is recorded.

• o Abluftvolumenstrom: minium
• o Zuluftvolumenstrom unten: minimum
• o Zuluftvolumenstrom oben und seitlich: aus

If the severity is very low, the control unit 7 can preferably carry out the following control:

• o Extract air volume flow: minimum
• o Supply airflow below: minimum
• o Supply air volume flow top and side: off

This scenario 1 (minimum or night operation) occurs very often (e.g. 50%). The extraction device 1 is not in operation, such as on weekends, at night or during breaks. This scenario 1 is in the 9 and 10 marked with SI.

The low degree of severity is present here, for example, in an operating state in which the slide 4 and, if present, the slide sections 41-43 are closed, there is preferably an isothermal state in the working space 2, no person or object in the area U of the extraction device 1 are detected, there are no pressure fluctuations in the working space 2, and a low energy consumption is detected.

• o Abluftvolumenstrom: gering
• o Zuluftvolumenstrom unten: minimum
• o Zuluftvolumenstrom oben und seitlich: aus

If the severity is low, the control unit 7 can preferably carry out the following control:

• o Extract air volume flow: low
• o Supply airflow below: minimum
• o Supply air volume flow top and side: off

This Scenario II (Small) is the second most common scenario (e.g. 15%). The access opening 20 is closed and automated processes are running. The amount of exhaust air is slightly increased (cf. SII in 10 ). In this scenario II, the lower nozzle bar section 60 runs easily (cf. SII 9 ) to accelerate the flow in the extraction device 1 or in the working space 2.

The medium degree of severity is present here, for example, in an operating state in which the slide 4 and, if present, the slide sections 41-43 are closed, there is preferably an isothermal state in the working space 2, no person or object in the area U of the extraction device 1 are detected, there are no pressure fluctuations in the working space 2, and an increased or high energy consumption is detected.

• o Abluftvolumenstrom: mittel
• o Zuluftvolumenstrom unten: minimum
• o Zuluftvolumenstrom oben und seitlich: mittel

If the degree of severity is medium, the control unit 7 can preferably carry out the following regulation:

• o Extract air volume flow: medium
• o Supply airflow below: minimum
• o Supply airflow top and side: medium

This scenario III (medium) is the second most common scenario (e.g. 15%). The access opening 20 is closed and automated processes take place, albeit with higher energy consumption. The amount of exhaust air is further increased (cf. SIII in 10 ). In this scenario III, the lower nozzle bar section 60 runs easily (cf. SIII in 9 ) to accelerate the flow in the extraction device 1 or in the working space 2. The other nozzle bar sections 61-63 are now also running in order to prevent leakage caused by the thermals at the upper slide edge.

The high degree of severity is present here, for example, in an operating state in which the slide 4 and, if present, the slide sections 41-43 are at least partially open, the temperature in the working space 2 is preferably elevated, a person is in the vicinity U of the extraction device 1 is detected, there are small pressure fluctuations in the working space 2, and a low energy consumption is detected.

• o Abluftvolumenstrom: höher
• o Zuluftvolumenstrom unten: hoch
• o Zuluftvolumenstrom oben und seitlich: hoch

If the degree of severity is high, the control unit 7 can preferably carry out the following control:

• o Extract air volume flow: higher
• o Supply airflow below: high
• o Supply air volume flow top and side: high

This scenario IV (high) is a possible companion scenario to scenario II (e.g. 5%). In scenario II, the user intervenes in the withdrawal device 1 or the work area 2, but does not yet produce any (significant) disturbances. In this scenario IV, health hazards for the user must be averted. The exhaust air volume must therefore be increased (cf. SIV in 10 ). In this scenario IV all nozzle bar sections 60-63 run at high speed (cf. SIV in 9 ) to accelerate the flow in the extraction device 1 or in the working space 2 and to shield the access opening 20.

The very high degree of severity is present here, for example, in an operating state in which the slide 4 and, if present, the slide sections 41-43 are at least partially open, there is preferably an increased temperature in the working space 2, a person in the vicinity U of the extraction device 1 is detected, there are small pressure fluctuations in the working space 2, and an increased or high energy consumption is detected.

• o Abluftvolumenstrom: hoch
• o Zuluftvolumenstrom unten: mittel
• o Zuluftvolumenstrom oben und seitlich: maximal

If the degree of severity is very high, the control unit 7 can preferably carry out the following regulation:

• o Extract air volume flow: high
• o Bottom supply airflow: medium
• o Supply air volume flow top and side: maximum

This scenario V (very high) is a possible companion scenario to scenario II (e.g. 5%). In scenario II, the user intervenes in the extraction device 1 or the work area 2 and creates disturbances. In this scenario V, health hazards for the user must be averted. The exhaust air volume must therefore be increased further (cf. SV in 10 ). Due to a high thermal load, there can be a high risk of a breakout in the upper area of the access opening 20 in particular. In this scenario V, the lower nozzle bar section 60 is no longer required at a high level, but the other nozzle bar sections (top and side) 61-63 run at a very high or maximum level (cf. SV in 9 ) to accelerate the flow in the extraction device 1 or in the working space 2 and to shield the access opening 20.

The maximum degree of severity is present here, for example, in an operating state in which the slide 4 and, if present, the slide sections 41-43 are at least partially open, the temperature in the working space 2 is preferably elevated, a person is in the area U of the extraction device 1 is detected, increased pressure fluctuations are present in the working space 2, and an increased or high energy consumption is detected.

• o Abluftvolumenstrom: maximal
• o Zuluftvolumenstrom unten: hoch
• o Zuluftvolumenstrom oben und seitlich: maximal.

If the maximum degree of severity is present, the control unit 7 can preferably carry out the following regulation:

• o Extract air volume flow: maximum
• o Supply airflow below: high
• o Supply air volume flow top and side: maximum.

This scenario VI (maximum) is a possible companion scenario to scenario II (e.g. 5%). In scenario II, the user intervenes in the extraction device 1 or the work area 2 and creates disturbances, for example in the print image of the extraction device 1. In this scenario VI, health hazards for the user must be averted. Therefore, the amount of exhaust air should be further increased or maximized (cf. SVI in 10 ). Due to a high thermal load, there can be a further increased risk of a break-out in the upper area of the access opening 20 in particular. In this scenario VI, the lower nozzle bar section 60 is not required at maximum level, but runs at high level to achieve a defined air flow, while the other nozzle bar sections (top and side) 61-63 are at maximum level (cf. SVI in 9 ) run to accelerate the flow in the extraction device 1 or in the working space 2 and to shield the access opening 20 .

Examples of different operating situations and possible controls of the extraction device 1 are described below.

1. Slider Closed

Since the openings are very small when the slider 4 is closed (e.g. only via the afterflow openings 21, 22), it is possible to work with a small amount of air. The extraction device 1 then requires, for example, only about 100 m ³ /h/m.

Since the air volume of 100 m ³ /h/lfm is very small, thermals, internal installations or very heavy gases can lead to problems. If these are detected, the extraction device 1 can then be operated, for example, with up to 200 m ³ /h/lfm when the slider 4 is closed.

1.1. problem case 1

Are there in the extraction device 1 disturbances due to thermal influences, it can lead to a Heat build-up in the upper part of the extraction device 1 or the working area 2 come. This can be detected using the temperature sensors T1, T2, T3. In this case, the amount of air should be increased even when the slider 4 is closed, otherwise eruptions will occur. For example, a sealing air through the upper nozzle bar section 61 can prevent this.

problem case 2

Heavy gases or obstructions in the extraction device 1 can cause problems even when the slider 1 is closed. Supply air volume flows, for example via the lower nozzle strip section 60, can lead to a stable flow on the tabletop 30. It accelerates the air in the working space 2 and pushes the heavy gases directly to the suction device 5 and further into the exhaust air system 100 .

advantage

With the slider 4 closed, the extraction device 1 or the suction device 5 can initially be lowered to, for example, 100 m ³ /h/m, since the system increases the air volume and regulates the nozzle bar sections 60-63 in the event of problems, i.e. depending on the operating parameters can.

2. Gate 4 and/or gate sections 41-43 open

With the gate 4 open, the area of the exposed access opening 20 is large, while the rate of entry is comparatively low. The take-off device 1 can, for example, be operated at approx. 200 m ³ /h/running meter without any problems.

Since the air volume of 200 m ³ /h/lfm is low, thermals, internal installations or very heavy gases can lead to problems. If these are detected, the extraction device 1 can then be operated, for example, with up to 400 m ³ /h/lfm when the slide 4 or slide sections 41-43 are open. A distinction must be made as to how the access opening is uncovered.

Vertical opening via slider 4

The uncovering of the access opening 20 by means of the slide 4 usually results in a symmetrical situation, since the slide 4 is opened over the entire width. The control unit 7 can then, for example, increase the amount of exhaust air in parallel with the slide opening. All supply air quantities (ie the supply air volume flows of the respective nozzle sections 60-63) can then be ramped up in parallel.

Horizontal opening via gate sections 41-43

The situation arising from the uncovering of the access opening 20 by means of the slide sections 41-43 is usually critical due to the thermals that occur. The reason is that the uncovering of the access opening by manual displacement of the slide sections 41-43 is equally large, is also often asymmetrical and, furthermore, an overall asymmetrical situation is created by internal transverse flows in the working space 2. In this case, the control unit 7 should preferably immediately increase the amount of exhaust air and, in particular, immediately activate or raise the lateral and upper nozzle bar sections 61-63.

problem case 3

When the slider 4 or slider sections 41-43 are open, a user usually stands in front of the extraction device 4 or the exposed access opening 20. This can lead to smaller turbulences in the following air around the user. If the user also reaches into the extraction device 1 or the working area 2, further disruptions can occur. A (temporary) increase in the amount of air is therefore urgently required and can be regulated directly according to the invention.

If several problem cases are combined, an increase in the exhaust air volume flow to 400 m ³ /h/lfm or more may be necessary.

advantage

The fume hood can also be lowered to 200 m ³ /h/lfm when the access opening 20 is (partially) uncovered, since the system can increase the air volume and regulate the nozzle bar sections 60-63 in the event of problems, i.e. depending on the operating parameters.

The present invention is not limited to the embodiments described above, as long as it is encompassed by the subject matter of the following claims. In particular, any combination of the above or other operating parameters can be used to control the extraction device 1 according to the invention.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 4402541 A1 [0005]
• US4741257 [0005]
• US5924920A [0006]
• US7470176 [0006]
• US5697838 [0006]
• DE 4040723 A1 [0007]
• DE 19545948 A1 [0038]

Claims (38)

Exhaust device (1), in particular for laboratory areas, having: • a housing (3) enclosing a working space (2) and having an access opening (20) for external access to the working space (2), • a movable slider (4) for selectively exposing or closing the access opening (20), • an adjustable suction device (5) for discharging exhaust air from the working area (2) into an exhaust air system (100), • Several nozzle bar sections (60-63) for the directed ejection of air into the working space (2) for a defined flow in the working space (2) and to prevent gases from escaping from the working space (2) via the access opening (20), the nozzle bar sections (60-63) can be controlled at least partially independently of one another, • sensor means (A1, A2, B1, B2, E, L1, L2, M1, M2, P, P1, P2, S1, S2, T1, T2, T3, Z) for detecting operating parameters of the extraction device (1), and • a control unit (7) for regulating an exhaust air volume flow of the suction device (5) and supply air volume flows of the nozzle bar sections (60-63) that can be controlled independently in each case as a function of the operating parameters. Trigger device (1) after claim 1 , wherein the housing (3) has a bottom wall (30), a top wall (31) and between the bottom wall (30) and the top wall (31) extending side walls (32-35) which together enclose the working space (2). Exhaust device (1) according to one of the preceding claims, wherein the nozzle bar sections (60-63) are arranged around the access opening (20) and preferably directly surrounding the access opening (20) in order to preferably eject the air in the area of the access opening (20). Extraction device (1) according to one of the preceding claims, wherein the nozzle bar sections (60-63) each have a large number of nozzle openings (64) preferably arranged in a row, the nozzle openings (64) particularly preferably tapering towards the working space (2). Extraction device (1) according to one of the preceding claims, wherein the nozzle bar sections (60-63) are each designed as an elongated nozzle bar, which preferably has a circular cross section and is particularly preferably rotatably mounted about its longitudinal axis in order to be able to adjust the ejection direction. Extraction device (1) according to one of the preceding claims, wherein the nozzle bar sections (60-63) comprise at least one of the following nozzle bar sections (60-63): • a lower nozzle bar section (60), preferably provided below the access opening (20), • an upper nozzle bar section (61), preferably provided above the access opening (20), • a lateral nozzle bar section (62, 63), preferably provided to the left and/or right of the access opening (20). Extraction device (1) according to one of the preceding claims, further comprising a plurality of fans (V1-V4), preferably DC-operated fans (V1-V4), for feeding the nozzle bar sections (60-63) with air, the fans (V1-V4 ) for controlling the supply air volume flows depending on the operating parameters can be controlled independently of one another, this particularly preferably continuously or in stages, such as to achieve a blow-out speed of 1 m / s, 1.5 m / s, 2 m / s, 2.5 m / s, 3 m /s, 3.5m/s and/or 4m/s. Trigger device (1) after claim 7 , each of the nozzle bar sections (60-63) or each of the jointly controllable or controllable nozzle bar sections (60-63) being assigned its own fan (V1-V4). Trigger device (1) after claim 6 as well as one of Claims 7 or 8th , wherein the lower nozzle bar section (60) is assigned its own fan (V1), and/or the upper nozzle bar section (61) is assigned its own fan (V2), and/or the lateral nozzle bar sections (62, 63) share a dedicated fan is assigned, and/or wherein the left-hand nozzle bar section (62) is assigned its own fan (V3), and/or wherein the right-hand nozzle bar section (63) is assigned its own fan (V4), and/or wherein the upper and the lateral nozzle strip sections (61-63) are jointly assigned their own fan. Extraction device (1) according to one of the preceding claims, wherein at least one of the nozzle bar sections (60-63), preferably at least the lateral and/or the lower nozzle bar section (60, 62, 63), is designed and arranged in such a way that this nozzle bar section ( 60-63) can eject a directed supporting jet along a housing wall (30-35) that delimits the working space (2) and is adjacent to the nozzle bar section (60-63). Extraction device (1) according to one of the preceding claims, wherein at least one of the nozzle bar sections (60-63), preferably at least the upper nozzle bar section (61), is designed and arranged in such a way that this nozzle bar section (60-63) produces a directed free jet in the Working space (2) in front of the access opening (20) can eject. Extraction device (1) according to any one of the preceding claims, wherein the access opening (20) is provided in one of the side walls (32-35). Extraction device (1) according to one of the preceding claims, wherein the movable slide (4) is provided so as to be translationally and preferably vertically displaceable, preferably along the housing wall or side wall (32) having the access opening (20). Extraction device (1) according to one of the preceding claims, in which the slide (4) can be moved steplessly. Extraction device (1) according to one of the preceding claims, in which the slide (4) can be moved electrically, the control unit (7) preferably being set up in such a way that it also regulates the slide position as a function of the operating parameters. Extraction device (1) according to one of the preceding claims, wherein the slide (4) has a plurality of movable slide sections (41-43) in order to selectively expose the slide (4) from the outside towards the working space (2), the slide sections (41-43 ) are preferably provided in a translatory and more preferably horizontally movable manner. Trigger device (1) after Claim 16 , wherein the sensor means have at least one section position sensor (P) for detecting the position of the movable slide sections (41-43) as one of the operating parameters, the section position sensor (P) preferably being an ultrasonic sensor, a light barrier sensor, a button and/or a switch is like a limit switch. Take-off device (1) according to one of the preceding claims, wherein the sensor means have at least one slide position sensor (M1) for detecting the position of the movable slide (4) as one of the operating parameters, the slide position sensor (M1) preferably being a cable sensor such as a Cable pull potentiometer, a button and/or a switch such as a limit switch. Extraction device (1) according to one of the preceding claims, wherein the sensor means at least one temperature sensor (T1) for detecting the temperature in the working space (2) as one of the operating parameters, and/or at least one temperature sensor (T3) for detecting the temperature in the environment ( U) of the extraction device (1) as one of the operating parameters, and/or at least two temperature sensors (T1, T3) for detecting a temperature difference between the working space (2) and the environment (U) as one of the operating parameters, and/or at least one temperature sensor (T2) for detecting the temperature of the exhaust air in the suction device (5). Extraction device (1) according to one of the preceding claims, wherein the sensor means have at least one pressure sensor (P1) for detecting the pressure in the working chamber (2) as one of the operating parameters, and/or at least two pressure sensors (P1, P2) for detecting a pressure difference at least between the working space (2) and the environment (U) or between two different areas in the working space (2) as one of the operating parameters. Extraction device (1) according to one of the preceding claims, wherein the sensor means at least one movement sensor (B1) for detecting movements in the area (U) of the extraction device (1) and preferably in front of the extraction device (1) or the access opening (20) as one the operating parameters, and/or at least one movement sensor (B2) for detecting movements in the working space (2) as one of the operating parameters. Extraction device (1) according to one of the preceding claims, wherein the sensor means at least one presence sensor (A1) for detecting the presence of objects or persons in the vicinity (U) of the extraction device (1) and preferably in front of the extraction device (1) or the access opening ( 20) as one of the operating parameters, and/or at least one presence sensor (A2) for detecting the presence of objects or people in the access opening (20) and/or in the work space (2) as one of the operating parameters. Exhaust device (1) according to one of the preceding claims, wherein the sensor means have at least one pollutant sensor (Si) for detecting pollutants in the working space (2) as one of the operating parameters, and/or at least two pollutant sensors (S1, S2) for detecting a pollutant difference between the Have workspace (2) and the environment (U) as one of the operating parameters. Exhaust device (1) according to one of the preceding claims, wherein the sensor means have at least one sensor (L1, L2) for detecting the volume of exhaust air from the suction device (5) as one of the operating parameters, and/or at least one sensor (M2) for detecting the amount of air from the working space (2) having the volume flow conducted into the exhaust air system (100) as one of the operating parameters, the sensor for detecting the amount of exhaust air or the volume flow being a pressure sensor (L1, L2) for detecting a pressure difference in the exhaust air line and/or a positioning sensor (M2) for detecting an adjustment position of a motor-operated adjustment flap (50) for controlling the suction device (5). Extraction device (1) according to one of the preceding claims, wherein the sensor means have at least one intake air quantity detection sensor (Z1, Z2, Z3), preferably for each nozzle bar section (60-63) that can be controlled or regulated independently of one another, for detecting the quantity of intake air via the respective nozzle bar sections (60-63). have one of the operating parameters. Extraction device (1) according to one of the preceding claims, wherein the sensor means have at least one energy detection sensor (E1, E2) for detecting the amount of energy currently consumed by the extraction device (1). Exhaust device (1) according to one of the preceding claims, wherein the suction device (5) is designed in such a way that the amount of exhaust air and/or the volume flow conducted from the work space (2) into the exhaust air system (100) is between 100 and 1500 m ³ /h/ m, preferably between 100 and 550 m ³ /h/m or between 200 and 850 m ³ /h/m or between 300 and 1500 m ³ /h/m. Extraction device (1) according to one of the preceding claims, wherein the suction device (5) is arranged above the working space (2), preferably on an upper housing wall or the ceiling wall (31), and wherein the housing wall assigned to the suction device (5) or the ceiling wall (31) is preferably designed for the most part as a perforated wall plate (36) in order to fluidically connect the working space (2) to the suction device (5). Extraction device (1) according to one of the preceding claims, wherein the slider (4) completely closes the access opening (20) in a rest position, partially exposes the access opening (20) in a working or engagement position, preferably with a height of about 450 mm, and in an open position, the access opening (20) is maximally or completely uncovered, preferably with a height of about 900 mm. Extraction device (1) according to one of the preceding claims, wherein the extraction device (1) has afterflow openings (21, 22) so that air can flow into the working chamber (2) even when the slide (4) is completely closed. Trigger device (1) according to one of the preceding claims, wherein the trigger device (1) has input means (8), such as a touch display, switch, controller, lever, button, and/or output means (9), such as display means, display, indicator lamps, having. Extraction device (1) according to one of the preceding claims, wherein the extraction device (1) has optical and/or acoustic alarm means (9). Method for operating an extraction device (1) according to one of the preceding claims, comprising: • detecting operating parameters of the extraction device (1), and • Regulating an exhaust air volume flow of the suction device (5) and supply air volume flows of the nozzle bar sections (60-63) that can be controlled independently in each case as a function of the operating parameters recorded. procedure after Claim 33 , being recorded as the operating parameters: • the position of the movable slide (4), • the position of the movable slide sections (41-43), • the temperature in the working space (2), • a temperature difference between the working space (2) and the Environment (U), • the temperature of the exhaust air in the suction device (5), • the pressure in the working space (2), • a pressure difference at least between the working space (2) and the environment (U), • a pressure difference at least between two different ones Areas in the workspace (2), • movements in the vicinity (U) of the trigger device (1) and preferably in front of the trigger device (1) or the access opening (20), • movements in the workspace (2), • the presence of objects or People in the vicinity (U) of the extraction device (1) and preferably in front of the extraction device (1) or the access opening (20), the presence of objects or persons in the access opening (20) and/or in the work space (2), • Sch pollutants in the working space (2), • a difference in pollutants between the working space (2) and the environment (U), • the amount of exhaust air from the suction device (5), • from the working space (2) into the exhaust air system (100) guided volume flow, • the supply air amount(s) via the respective nozzle bar sections (60-63), • the amount of energy currently consumed by the extraction device (1). procedure after Claim 33 or 34 , wherein the control unit (7) is set up: • to assign the operating state of the extraction device (1) to one of several predefined degrees of severity as a function of the operating parameters, and • to regulate the exhaust air volume flow and the respective supply air volume flows according to the assigned degree of severity, with the operating parameters preferably being continuous or are recorded regularly, the assignment and/or the regulation preferably also being carried out continuously or regularly. procedure after Claim 35 wherein the severities include at least a low severity and a high severity, preferably further comprising a very low severity and/or a medium severity and/or a very high severity and/or a maximum severity. procedure after Claim 36 , wherein • the very low or low degree of severity is present in an operating state in which the slide (4) and, if present, the slide sections (41-43) are closed, in the working space (2) there is preferably an isothermal state, no person or object is detected in the environment (U) of the extraction device (1), there are no pressure fluctuations in the working space (2), no energy consumption is detected, • the low degree of severity is present in an operating state in which the slider (4) and, if present, the slide sections (41-43) are closed, the working area (2) is preferably isothermal, no person or object is detected in the area (U) of the extraction device (1), there are no pressure fluctuations in the working area (2), a low Energy consumption is detected, • the medium degree of severity is present in an operating state in which the slider (4) and, if present, the slider sections (41-43) are closed, in Ar Working space (2) is preferably isothermal, no person or object is detected in the vicinity (U) of the extraction device (1), there are no pressure fluctuations in the working space (2), increased or high energy consumption is detected, • the high degree of severity in there is an operating state in which the slide (4) and, if present, the slide sections (41-43) are at least partially open, the temperature in the working space (2) is preferably elevated, a person is in the vicinity (U) of the extraction device ( 1) is detected, there are small pressure fluctuations in the working space (2), low energy consumption is detected, • the very high degree of severity is present in an operating state in which the slide (4) and, if present, the slide sections (41-43) at least are partially open, the temperature in the working space (2) is preferably elevated, a person is detected in the vicinity (U) of the extraction device (1), low pressure fluctuations conditions are present in the working space (2), an increased or high energy consumption is detected, • the maximum degree of severity is present in an operating state in which the slide (4) and, if present, the slide sections (41-43) are at least partially open, in Working space (2) preferably an increased temperature prevails, a person is detected in the area (U) of the extraction device (1), increased pressure fluctuations in the working space (2) are present, increased or high energy consumption is detected. procedure after Claim 36 or 37 , whereby the control unit (7) carries out the following control in the presence of the following severity level: • very low severity level: o extract air flow: minimum o supply air flow below: minimum o supply air flow above and to the side: off • low severity: o extract air flow: low o supply air flow below: minimum o Supply airflow top and side: off • medium severity: o Extract airflow: medium o Supply airflow bottom: minimum o Supply airflow top and sides: medium • high severity: o Extract airflow: higher o Supply airflow bottom: high o Supply airflow top and sides: high • very high Severity: o extract airflow: high o supply airflow bottom: medium o supply airflow top and sides: maximum • maximum severity: o extract airflow: maximum o supply airflow bottom: high o supply airflow top and sides: maximum.

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