Exhaust vent with lockable openings for cables

Abstract

A fume hood comprising a housing that separates an interior space from its surroundings, wherein the housing has a bottom working surface, a roof, a rear wall, side walls, and a front with a movable front slide, wherein at least one wall (10) has an opening (12) that can be closed by a closing element (20) for the passage of lines (30) from the surroundings into the interior space, wherein the closing element (20) is arranged to be displaceable parallel to the wall (10) forming a clamping area (32) for the lines (30) between an edge (14) of the opening and an end (22) of the closing element, characterized in that the closing element (20) is arranged in the interior space.

Description

The invention relates to a trigger comprising a housing which delimits an interior space with respect to the surroundings, wherein the housing has a base-side working surface, a roof, a rear wall, side walls, and a front side with a movable front slide, wherein an opening which can be closed by a closure element is present in at least one wall for the passage of lines from the surroundings into the interior space.Such prints are used, inter alia, in laboratories to carry out work with potentially hazardous substances in defined environments. Their possible designs and configurations are described, inter alia, in European standard DIN EN 14175-1:2003.The main object of prints is to encapsulate the atmosphere in the interior space with respect to the environment in such a way that no substances pass from the interior space into the environment. This must also be ensured, for example, when the front side of the trigger is partially open. In order to achieve this, suction devices are usually provided on the exhausts, which suction the atmosphere of the interior through channels which are sealed off from the environment, for example via the roof of the exhaust.The document DE 10 2011 077 837 A1 describes a trigger which comprises a housing delimiting a working chamber, wherein the housing has an air inlet opening. In an inflow region formed by the supply air opening, an additional suction opening is provided. Upstream of the auxiliary suction opening, a device is provided for accelerating a flow layer of incoming supply air close to the wall.The document DE 20 2018 105 102 U1 describes a trigger of the generic type in which an additional suction connection is provided in the work plate or the rear wall.Often, not all equipment required to perform potentially hazardous operations can be accommodated in a fume hood due to the lack of available work surface. In such a case, those equipment which are not critical with respect to the danger potential are placed outside the trigger, while the remaining equipment is built up in the trigger. Examples of equipment are storage containers, balances, metering devices such as pumps or dropping funnels, mixing devices, reactors, stirring devices such as magnetic stirrer or stirring motors, temperature control devices such as oil baths, water baths, baths with cold mixtures or heating hoods, separating devices such as separating funnels or columns, sensors, measuring devices, analytical instruments, controllers, wash bottles, wash towers, cold traps.However, this requires the passage of lines from the environment into the interior. These lines can be cables for electrically connecting equipment in the trigger, for example to a power supply outside the trigger, or cables for connecting sensors in the trigger to analysis devices or measurement devices outside the trigger. The lines can also be hoses, for example for supplying or discharging gaseous or liquid substances.Challenges in the design of openings for the passage of lines are, inter alia, that the openings should on the one hand be as small as possible in order to shield the atmosphere of the interior from the environment, but on the other hand should be given flexibility with regard to the lines to be passed, which can have different diameters. Thus, for example, cables for electrical connections can have a diameter in the range of a few millimeters, whereas lines for fluids can certainly have a diameter of several centimeters. A further challenge is that the openings should be closed as tightly as possible when no lines are passed through. Various approaches are known from the prior art for designing conduits to pass through openings in the vent.In a known solution, the opening is designed as a rubber lip which can be elastically deformed. An advantage of this solution is that lines of different diameters can be made flexible and the rubber lip is placed around the lines so that the remaining opening area is small. However, a disadvantage of this solution is that the material of the rubber lip becomes brittle over time or plastically deforms and therefore regularly has to be controlled for its sealing function and optionally exchanged. A further disadvantage is that in the event of an overpressure in the trigger, the rubber lip is pressed outwards and substances can escape from the interior of the trigger into the environment. Likewise, in the event of a vacuum in the trigger, substances can pass from the environment through an leaking rubber lip into the interior of the trigger, which is likewise undesirable.Another known solution is disclosed in the document DE 85 09 333 U1. Openings are provided in a side wall in a trigger, for example for the passage of cables for electrical connections. On the outside of the side wall are arranged displaceable plates by means of which the openings can be closed.Another known solution is brushes made of plastic which fulfil a function comparable to the rubber lips. An advantage of this solution is that lines of different diameters can be made flexible and the brushes are placed around the lines so that the remaining opening area is small. However, a disadvantage of this solution is that the material of the brushes becomes brittle over time or plastically deformed and therefore regularly has to be controlled for its sealing function and optionally exchanged. A further disadvantage is that in the event of an overpressure in the trigger, the brushes are pressed outwards and substances can escape from the interior of the trigger into the environment. In addition, the brushes are at risk that, at a high temperature in the trigger, the brushes melt and, as a result, substances can escape from the interior of the trigger into the environment or undesired substances can pass from the environment into the interior of the trigger.Another known solution with a different mode of action is a so-called iris. These are circular openings in which overlapping circle sectors are arranged displaceably in the circumferential direction. The circle sectors are usually made of metal or plastic. By displacing the circle sectors relative to each other, the opening cross section can be varied and thus adapted to the lines to be carried out. An advantage of this solution is that it closes tightly and is stable under pressure. The disadvantage is that this solution is complicated and expensive. In addition, the circle sectors can slip over time, for example due to vibrations of the extraction housing or movements of the lines led through, as a result of which the opening widens and substances from the interior of the extraction device can pass into the environment or undesired substances from the environment can pass into the interior of the extraction device.It is an object of the invention to further develop known flues in such a way that conduits of different cross-sections can be guided flexibly and easily through openings in the wall of the flue. In this case, the opening area should be minimized when lines are passed through and the opening should be completely closed when not in use. The closure device should also withstand an overpressure in the trigger, so that the opening remains closed.This object is achieved according to the invention by a trigger according to claim 1.The trigger according to the invention comprising a housing which delimits an interior space with respect to the environment, wherein the housing has a floor-side working surface, a roof, a rear wall, side walls, and a front side with a movable front slide. In at least one wall, an opening closable by a closure element is provided for the passage of lines from the environment into the interior space. The closure element is arranged so as to be displaceable parallel to the wall, forming a clamping region for the lines between an edge of the opening and an end of the closure element. The arrangement of the closure element parallel to the wall has the advantage that it is space-saving and simple to realize. In addition, the closure element can be designed in a pressure-tight and sealing manner in this way. The closure element is arranged in the interior of the drain. This arrangement has the advantage that in the event of an overpressure in the interior of the trigger, the closure element is pressed in the direction of the wall, which assists the sealing of the opening.Advantages of forming a clamping region for the lines between an edge of the opening and an end of the closure element are that lines of different cross sections can be guided through the opening and are fixed in the clamping region. The opening area available for the passage of the lines can be flexibly adapted to the respective requirements by a simple displacement of the closure element. A further advantage is that the opening area between the interior of the drain and the environment, which is not occupied by lines, is minimized. If there are no lines in the opening, the opening is completely closed by the closure element.The at least one closable opening for the passage of lines is located in a wall, preferably in a side wall or in the rear wall. According to the invention, a plurality of openings can also be located in the same wall or in a plurality of walls. Preferably, in the case of a plurality of openings, all openings are provided with a closure element which is arranged such that it can be displaced parallel to the wall, forming a clamping region for the lines between an edge of the respective opening and an end of the associated closure element.In a preferred embodiment, the edge of the opening forming the clamping region has at least one concave-shaped indentation. According to the invention, a concave-shaped indentation is understood to mean an indentation that extends from the opening in the direction of the wall. The indentation can have any desired shape, for example curved, oval, ellipsoidal, circular, angular, polygonal or combinations thereof.In a development of this preferred embodiment, the edge of the opening forming the clamping region has a plurality of concave-shaped indentations. The plurality of indentations may be identical or different in shape, for example with respect to the shape of the indentation or the size of the indentation.The concave configuration of the edge of the opening forming the clamping region has the advantage that the lines guided through the opening collect in the indentation and the free opening area remaining after the closure element has been pushed onto the lines is thereby further minimized.In a further preferred embodiment, the edge of the opening forming the clamping region is formed by a shaped part which is detachably fastened to the wall. The fastening can be effected in different ways, for example by fitting the molded part onto the wall, hooking or screwing. This embodiment has the advantage that the edge of the opening can be easily and flexibly adapted to the respective requirements with respect to the lines to be guided through the opening without any changes having to be made to the wall.In a development of this preferred embodiment, the molded part has at least one concavely shaped indentation on its part forming the clamping region. The indentation can have any desired shape, for example curved, oval, ellipsoidal, circular, angular, polygonal or combinations thereof.In a further development of this preferred embodiment, the molded part has a plurality of concave-shaped indentations on its part forming the clamping region. The plurality of indentations may be identical or different in shape, for example with respect to the shape of the indentation or the size of the indentation.As in an embodiment with a concave shaped edge of the opening, the concave shape of the part of the molded part forming the clamping region has the advantage that the lines guided through the opening collect in the indentation and thereby the free opening area remaining after the pushing of the closure element onto the lines is further minimized.In a further preferred embodiment, the end of the closure element forming the clamping region has at least one concavely shaped indentation. According to the invention, a concave-shaped indentation with respect to the closure element is understood to mean an indentation which extends from the opening in the direction of the closure element.The indentation can have any desired shape, for example curved, oval, ellipsoidal, circular, angular, polygonal or combinations thereof.In a development of this preferred embodiment, the end of the closure element forming the clamping region has a plurality of concave-shaped indentations. The plurality of indentations may be identical or different in shape, for example with respect to the shape of the indentation or the size of the indentation.The concave configuration of the end of the closure element forming the clamping region has the advantage that the lines guided through the opening collect in the indentation and the free opening area remaining after the closure element has been pushed onto the lines is thereby further minimized.In a further preferred embodiment, the end of the closure element forming the clamping region is formed by a shaped part which is detachably connected to the closure element. The fastening can be effected in different ways, for example by plugging the molded part onto the closure element, hooking it in or screwing it on. This embodiment has the advantage that the edge of the opening can be easily and flexibly adapted to the respective requirements with regard to the lines to be guided through the opening.In a development of this preferred embodiment, the molded part has at least one concavely shaped indentation on its part forming the clamping region. The indentation can have any desired shape, for example curved, oval, ellipsoidal, circular, angular, polygonal or combinations thereof.In a further development of this preferred embodiment, the molded part has a plurality of concave-shaped indentations on its part forming the clamping region. The plurality of indentations may be identical or different in shape, for example with respect to the shape of the indentation or the size of the indentation.As in an embodiment with a concave shaped edge of the closure element, the concave shape of the part of the molded part forming the clamping region has the advantage that the lines guided through the opening collect in the indentation and thereby the free opening area remaining after the closure element has been pushed onto the lines is further minimized.In a further preferred embodiment, the closure element is interchangeably fastened to the wall. In the context of the present invention, institutability is understood to mean that the closure element can be removed from the wall. An advantage of this embodiment is the flexible and adaptable design of the closure element. A further advantage is seen in the fact that by removing the closure element from the wall, the entire opening region of the passage is accessible, which facilitates, for example, working on the opening.In a further preferred embodiment, the closure element comprises a plate which is guided in guide rails fastened to the wall. The guide rails can be glued to the wall or screwed to the wall, for example. In alternative embodiments, the guide rails can also be integrally connected to the wall, for example if the wall and guide rails are produced from a solid material or by an additive manufacturing method (3D printing). By configuring it as a plate, the closure element can be easily handled. The plate is preferably made of a rigid material, for example a metal or plastic. It is furthermore preferred that the plate is made of a material which is pressure-resistant, temperature-resistant and / or chemical-resistant. A preferred material for the closure plate is polytetrafluoroethylene (PTFE).In a further preferred embodiment, the closure element is displaceable in the vertical direction from above via the opening. The clamping region is formed in this case between the lower end of the closure element and the lower edge of the opening. An advantage of this embodiment is that the closure element slides down over the opening due to gravity. As a result, on the one hand, the opening region is minimized in the case of existing lines, and on the other hand, the opening is completely closed when not in use, without further measures being necessary.Particularly preferred is an embodiment in which the closure element comprises a plate which is guided in vertical guide rails fastened to the wall, so that the closure element can be displaced in the vertical direction from above via the opening.In a further preferred embodiment, the closure element has a handle at its end facing away from the clamping region. As a result, the closure element can be handled in a simple manner.The invention is explained in more detail below with reference to the drawings. The drawings are to be understood as schematic representations. They do not constitute a limitation of the invention, for example with regard to specific dimensions or design variants. The following are shown: FIG. 1 : Plate guided in guide rails as an embodiment of a closure element according to the invention in the completely closed state. FIG. 2 : closure element according to FIG. 1 with clamped lines. FIG. 3 : Plate guided in guide rails with a concave indentation as a variant of the closure element according to FIG. 2List of reference numerals used:10 Wall 12 Opening 14 Edge of the opening 20 Closure element 22 End of the closure element 24 Guide rail 26 Handle 30 Line(s) 32 Clamping regionExample:FIGS. 1 and 2 schematically show an embodiment according to the invention of a closure element for a trigger in a plan view (in each case left illustration) and a side view (in each case right illustration). The trigger, which is not shown as a whole in FIGS. 1 and 2, comprises a housing which delimits an interior space of the trigger with respect to the environment, wherein the housing has a floor-side working surface, a roof, a rear wall, side walls, and a front side with a movable front slide. FIGS. 1 and 2 show a detail from a side wall 10 of the flue, in which a circular opening 12 is present for the passage of lines 30 from the environment into the interior of the flue. Due to the circular shape of the opening 12, its edge 14 has a concave-shaped indentation.The opening 12 can be closed by a closure element 20 which is arranged such that it can be displaced parallel to the wall 10. The closure element 20 comprises a plate which is guided in guide rails 24 fastened to the wall 10. The two guide rails 24 are fastened, for example adhesively bonded or screwed, perpendicularly to the wall 10 in the interior of the trigger and have, on the mutually facing sides, a groove in which the plate as closure element 20 can be displaced from above in the vertical direction via the opening 12. The plate can be removed completely from the guide rails 24 upwards and can thus be exchanged. At its upper end, the plate has a handle 26 for easy manual operation.FIG. 1 shows the closure element 20 in the completely closed state. The handle 26 of the plate rests on top of the guide rails 24, so that the plate cannot slide downward. The plate as a closure element 20 is dimensioned such that it completely covers the opening 12.In FIG. 2, the same device is shown in a state in which lines 30 are led through the opening 12 from the environment into the interior of the drain. The lines 30 can be, for example, cables for the electrical supply or data connection of equipment in the interior of the extraction device. They can also be hoses for the pneumatic or hydraulic supply of equipment in the interior of the trigger. Furthermore, these may be hoses for transporting liquids or gases between the interior of the flue and its environment. Examples of equipment are storage containers, scales, metering devices, mixing devices, reactors, stirring devices, temperature control devices, separating devices, sensors, measuring devices, analytical instruments, controllers, wash bottles, wash towers, cold traps. The leads 30 rest on the lower edge 14 of the opening 12. The plate as a closure element 20 is pushed onto the lines 30 from above, so that its lower end 22 rests on the lines 30. Due to gravity, the plate presses on the lines 30, so that a clamping region 32 for the lines 30 is formed between the edge 14 of the opening and the end 22 of the closure element.FIG. 3 schematically shows a variant of the embodiment according to FIGS. 1 and 2, in which only the plate is designed in a different manner. The plate as a closure element 20 has a concave-shaped indentation at its end 22 forming the clamping region 32. Depending on the number and diameter of the conduits 30 being passed through, by replacing the straight or concave shaped end plate 22, the remaining opening area in the opening 12 can be minimized. This can be realized in a simple manner by replacing plates.Example:A commercially available laboratory flue was converted according to the invention in accordance with FIGS. 1 and 2. The trigger comprises a housing which delimits an interior space of the trigger with respect to the environment and which has a floor-side working surface, a roof, a rear wall, side walls, and a front side with a movable front slide. A circular hole having a diameter of 80 mm was drilled into a side wall 10 of the trigger as opening 12. On the right and left of the opening 12, a guide rail 24 made of plastic with a length of 120 mm was glued perpendicularly to the inside of the side wall 10. The guide rails had an L-shaped profile.A plate made of plastic with a width of 110 mm and a height of 125 mm was used as the closure element 20. The upper end of the plate 20 was bent at a height of 15 mm away from the wall by approximately 90°, so that the bent part can be used as a handle. The handle also serves as a stop which prevents the plate 20 from sliding completely down through the guide rails 24. The plate can be removed completely from the guide rails 24 upwards and can thus be exchanged. The plate is dimensioned such that in the closed state it completely covers the opening 12.

Claims

A trigger comprising a housing which delimits an interior space with respect to the environment, wherein the housing has a base-side working surface, a roof, a rear wall, side walls, and a front side with a movable front slide, wherein an opening (12), which can be closed by a closure element (20), for the passage of lines (30) from the environment into the interior space is present in at least one wall (10), wherein the closure element (20) is arranged displaceably parallel to the wall (10), forming a clamping region (32) for the lines (30) between an edge (14) of the opening and an end (22) of the closure element, characterized in that the closure element (20) is arranged in the interior space.Trigger according to claim 1, characterised in that the edge (14) of the opening forming the clamping region (32) has at least one concave-shaped indentation.Trigger according to claim 1 or 2, characterised in that the edge (14) of the opening forming the clamping region (32) is formed by a shaped part which is detachably fastened to the wall (10).Trigger according to one of claims 1 to 3, characterised in that the end (22) of the closure element forming the clamping region (32) has at least one concave-shaped indentation.Trigger according to one of claims 1 to 4, characterised in that the end (22) of the closure element forming the clamping region (32) is formed by a shaped part which is detachably connected to the closure element (20).Trigger according to one of Claims 1 to 5, characterized in that the closure element (20) is fastened to the wall (10) in an exchangeable manner.Trigger according to one of Claims 1 to 6, characterized in that the closure element (20) comprises a plate which is guided in guide rails (24) fastened to the wall (10).Trigger according to one of claims 1 to 7, characterised in that the closure element (20) is displaceable in the vertical direction from above via the opening (12).Trigger according to one of Claims 1 to 8, characterized in that the closure element (20) has a handle (26) at its end facing away from the clamping region (32).

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