Suction device

Abstract

The invention relates to a device for suctioning cuttings which accumulate during a drilling process, comprising a first housing part (1) which has a negative pressure chamber (3), wherein a first suction channel (7) fluidically connects the negative pressure chamber (3) to a suction connector (14) which has a wall with a circular cross-section for plugging a hose (48), and comprising a second housing part (2, 2', 2'') which has a suction chamber (4), a second suction channel (8) fluidically connecting the suction chamber (4) to the suction connector (14). According to the invention, the wall of the suction connector (14) is formed by walls (15, 16), each of which is formed by one of the housing parts.

Description

Description Suction device field of technology

[0001] The invention relates to a device for sucking out drilling debris produced during drilling, comprising a first housing part which has a vacuum chamber, wherein a first suction channel fluidly connects the vacuum chamber to a suction nozzle which has a wall with a circular cross-section for attaching a hose, and comprising a second housing part which has a suction chamber, wherein a second suction channel fluidly connects the suction chamber to the suction nozzle, wherein the two housing parts are detachably connected to one another. State of the art

[0002] A device for extracting drilling debris with two chambers connectable to a suction device, one of which is a vacuum chamber and the other a suction chamber, is described in US Pat. No. 6,851,900 B2. The suction chamber is formed by an insert that can be inserted into a space enclosed by a wall.

[0003] A dust extraction device with a vacuum chamber and a suction chamber to which separate hoses can be connected is known from US 3,351,143. Furthermore, DE 2744463 A1, DE 35 01 753 A1, DE 36 00 626 A1, DE 4238564 A1, DE 7730552 U1, DE 19543599 A1, DE 102013 215 788 A1, DE 10 2018 214614 A1, DE 20 2008 008 561 U1, EP 0 799 674 A1, EP 2206579 B1, EP 2335868 B1, EP 2474 386 A1 and EP 3 632638 A1 describe dust extraction devices for use together with a hand drill. Summary of the invention

[0004] The invention is based on the object of developing a generic device in a manner that is advantageous in use.

[0005] The problem is solved by the invention specified in the claims, wherein the subclaims are not only advantageous developments of the invention specified in claim 1, but also independent solutions to the problem.

[0006] Firstly and essentially, it is proposed that the wall of the suction nozzle is formed by one of the two housing parts. Each suction nozzle forms two suction channels, one suction channel being connected to the vacuum chamber and another suction channel being connected to the suction chamber. The two housing parts can be firmly connected to one another. Preferably, they are detachably connected to one another so that they can be replaced with differently designed housing parts. The first housing part, which forms the vacuum chamber, with the aid of which the device can adhere to a workpiece or other surface into which a hole is to be drilled by generating a vacuum, can be connected to a first, second housing part which has a suction chamber with a small diameter, for example to drill a hole with a small diameter.The first housing part can also be connected to a second, further housing part, which has a suction chamber with a larger diameter, so that a hole saw can be inserted into the suction chamber to drill a hole with a larger diameter. However, it is also envisaged that a second housing part can have a suction chamber into which an insert can be inserted, with which the effective diameter of the opening of the suction chamber can be reduced. It is considered advantageous if the two housing parts each form an end wall. The two end walls can have flat outer surfaces that can lie against one another. The two end walls can continue into the extraction nozzle. The extraction nozzle preferably has a circular outline. The extraction nozzle can have the shape of a circular cylinder. The extraction nozzle can taper towards its opening. It can be a slightly conical extraction nozzle. The extraction nozzle can be split in the middle, with a partition wall preferably being provided. Preferably, two partition walls lying next to one another are provided. One of the two partition walls is formed by the end wall of the first housing part and the other partition wall by the end wall of the second housing part. Each of the two housing parts can form semicircular walls of the extraction nozzle, which are each connected to a partition wall, so that the two suction channels can have a semicircular outline.The vacuum chamber has a closed top and an opening that is open at the bottom. The opening can extend over the entire footprint of the first housing part. With this opening, the device is brought against a wall extending in a plane, for example a workpiece or a building wall. It can be provided that one edge of the opening is formed by an elastic sealing lip. The edge of the opening and in particular the elastic sealing lip is brought against the wall of the workpiece. The vacuum chamber is then closed by this wall of the workpiece, so that a negative pressure can build up in the vacuum chamber when a suction device is connected to the extraction nozzle, with which air can be sucked out of the vacuum chamber. The negative pressure that develops in the vacuum chamber causes a force that holds the device to the wall.The suction chamber, formed by the second housing part, is open to the workpiece, with the opening of the suction chamber extending essentially in the plane of the workpiece. One edge of the opening of the suction chamber can be surrounded by a sealing lip. The sealing lip is preferably located in the same plane as the base. pressure chamber surrounding the sealing lip. Both sealing lips thus lie on the wall of the workpiece to be machined when the device is in the position of use. The first housing part and the second housing part can each have an upper side. The upper sides can lie in a common plane to one another, so that the two upper sides are aligned with one another. The extraction nozzle can emerge from these upper sides, with one half of the extraction nozzle being able to emerge from one of the two upper sides. The two housing parts can be connected to one another using detachable fastening means, with the fastening means being arranged in the region of end walls of the two housing parts that run parallel to one another, according to a preferred exemplary embodiment. Two different fastening means can be provided, with fastening means being provided in the lower region of the end wall and fastening means in the upper region of the end wall.A web can protrude approximately at a right angle from one of the two dividing walls, in particular the end wall formed by the first housing part. The web preferably protrudes from the lower end of the end wall, which runs in the region of the edge of the opening. Two openings can be provided in this web, into which pins formed by the second housing part can engage. In the assembled state, the end walls of the two housing parts can lie against one another in a touching manner. This can be a surface contact. It can also be provided that tabs protrude essentially at a right angle from one end wall. The tabs preferably protrude from the upper region of the end walls and particularly preferably from the end wall of the second housing part. In the region of the upper side of the first housing part, recesses open towards the end wall can be provided. The recesses can have a base into which a fastening screw can be screwed.When assembled, each tab rests in one of the recesses. A screw, screwed into the base of the recess, engages through the mounting holes in the tabs. According to a variation of the invention, a Dovetail groove a dovetail tongue. It is provided that two dovetail grooves running parallel to one another are arranged in one end wall and two dovetail tongues are formed from the other end wall, each extending in a vertical direction. The first housing part can have two opposing indentations and form a housing wall that surrounds the vacuum chamber. The second housing part can have an outer wall that defines the outline of the second housing part. The outer wall of the second housing part preferably merges flush with the housing wall of the first housing part. The second housing part can have an inner wall that surrounds the suction chamber. The inner wall can surround a circular-cylindrical suction chamber that is open both on the underside and on the top. The inner wall can be connected to the outer wall of the second housing part by one or more webs.Cavities can thus be provided between the inner wall and the outer wall. The suction chamber is preferably spaced from the end wall. A flow channel can be formed within the second housing part, extending between the suction chamber and the end wall. The flow channel can be closed at the top by the upper housing wall, which forms the top side of the second housing part. The flow channel can be closed at the bottom with a cover plate, wherein this cover plate can also close the cavities between the inner wall and the outer wall of the second housing part. The flow channel can have two side walls running parallel to one another, wherein these side walls extend between the end wall and the inner wall of the second housing part.The inner wall of the second housing part can surround the suction chamber continuously between one side wall and the other side wall of the flow channel, extending in a circular arc. The distance between the two inner walls can be approximately equal to the diameter of the suction nozzle. The essentially rectangular opening of the flow channel to the suction chamber can also have a width. which corresponds to the diameter of the suction nozzle. In a further development of the invention, it is provided that an insert piece can be inserted into the suction chamber, wherein the outer diameter of the insert piece, which essentially has a circular cylindrical shape, corresponds to the inner diameter of the suction chamber of the second housing part. The insert piece can be clamped in the suction chamber. However, it can also be screwed into the suction chamber. The insert piece, like the second or the first housing part, can be made of plastic. It can have an outer wall extending on an arc of a circle, which has a slot-shaped opening for dust extraction. The insert piece can form an inner wall extending on an arc of a circle, which surrounds a suction chamber of the insert piece. The outer wall and the inner wall preferably run coaxially to one another.Webs can be provided which connect the inner wall to the outer wall so that cavities can form between the inner and outer walls. These cavities can be closed on one side, in particular at the bottom, by a base to which the inner and outer walls are connected in a single material. The cavities can be closed on one side, in particular at the top, by a circular cover. The cover can have an inner edge surrounding a circular opening whose diameter corresponds to the inner diameter of the insert piece. The cover can lie in a recess so that the outer edge of the cover is surrounded by the outer wall. The insert piece can have a flow channel; the flow channel can be narrower than the flow channel of the second housing part. The flow channel of the second housing part is preferably directed towards the center of the suction chamber.The flow channel of the insert is also directed radially toward the center of the suction chamber. Both flow channels are connected to each other. The flow channel of the insert is closed at the top by the cover. The cover preferably has an extension that corresponds to the material thickness of the outer wall. and with which the flow channel is closed at the top in the area of ​​the outer wall. At the bottom, the flow channel is closed by an area of ​​the base. The second housing part can be easily detached from the first housing part and replaced with another housing part, for example with a housing part in which the diameter of the suction chamber is larger or smaller. The invention relates in particular to a device which has a first housing part and a plurality of second housing parts and / or an insert piece. Such a set can, for example, have a second housing part which has a fork shape. The housing part can have two outer housing walls which project in a fork-like manner from a rear end wall and which delimit a flow channel. The upper side of the second housing part can form a suction chamber extending over a semicircle.The suction chamber forms a broad side opening approximately in the area of ​​the diameter of this semicircle. Short description of the drawings

[0007] The invention is explained in detail below with reference to the accompanying drawings. They show: Fig. 1 is a first perspective view of a device according to the invention with a second housing part, in the suction chamber of which an insert piece 30 is inserted; Fig. 2 is a plan view of the embodiment shown in Fig. 1; Fig. 3 is a view of the embodiment shown in Figure 1; Fig. 4 is a section along the line IV-IV in Fig. 2; Fig. 5 is a section along the line VV in Fig. 2; Fig. 6 the two housing parts in the area of ​​their end faces 12, 13 in the separated state; Fig. 7 shows the section along the line VII - VII in Fig. 3; Fig. 8 is an exploded view of the embodiment; Fig. 9 is an exploded view of the insert 30; Fig. 10 is a perspective view from above of a first housing part connected to a second embodiment of the second housing part; Fig. 11 shows the embodiment shown in Fig. 10 in a perspective view from below; Fig. 12 is a perspective view from above of a first housing part connected to a third embodiment of the second housing part; Fig. 13 the embodiment shown in Fig. 12 in a perspective view from below and Fig. 14 alternative fastening means. Description of the embodiments

[0008] The drawings show various embodiments of a device for suctioning away drilling debris, the device comprising a first housing part 1, which essentially has the task of temporarily attaching the entire device to a building wall by generating a vacuum. For this purpose, the first housing part 1 forms a vacuum chamber 3, which is closed by a housing wall 43, an end wall 12, and an upper wall except for a lower opening 5 and a suction channel 7 opposite thereto. The lower opening 5 has an edge that runs in one plane. Arranged on the edge is a sealing lip 6 made of an elastic material that can be brought into contact with the building wall.If the suction channel 7 is connected to a suction device, for example a vacuum cleaner, a negative pressure is generated within the vacuum chamber 3, which develops a force with which the first housing part 1 adheres to the building wall.

[0009] The suction channel 7 opens into a suction nozzle 14. The suction nozzle 14 has a circular outline and is diametrically divided into two parts. One half of the suction nozzle 14 forms the suction channel 7 connected to the vacuum chamber 3. The other half of the suction nozzle 14 forms a suction channel 8, which is fluidly connected to a suction chamber 4 in order to generate an air flow in the suction chamber 4, with which drilling debris or other dust can be extracted from the suction chamber 4 when a hole is drilled through the suction chamber 4 into the building wall using a drill (not shown in the drawings).

[0010] The first housing part 1 forms a plane extending End wall 12, which extends downwards to the edge of the housing wall 43 and which extends upwards to a partition wall 17, which Suction channel 7 is limited. The housing wall 43 runs on a circular arc line on the side opposite the end wall 12 and otherwise has two opposing indentations 28.

[0011] The partition wall 17 is connected to a semicircular wall 15 of the suction nozzle 14. The partition wall 17 rests in contact with a partition wall 18 of the second housing part 2 forming the suction chamber 4. Here, too, the partition wall 18 is formed by a front wall 13 extending in a plane, which in the exemplary embodiment is congruent with the front wall 12 of the first housing part 1.

[0012] The suction chamber 4 is spaced apart from the end wall 13. Two side walls 47 adjoin the end wall 13, defining a flow channel 9 that has an opening to the suction chamber 4 and is connected to the suction channel 8, which is also surrounded by a semicircular wall 16 and a partition wall 18. The flow channel 9 has a rectangular cross-section and is bounded at the top by the upper side of the second housing part. The flow channel 9 is bounded at the bottom by a cover plate 10.

[0013] The upper side 25 of the second housing part 2 extends approximately in the same plane as the upper side 24 of the first housing part. The two upper sides 24, 25 extend essentially in a plane parallel to the plane in which the edge 6 of the opening 5 extends.

[0014] The suction chamber 4 is open both at the bottom and at the top. The lower edge of the suction chamber 4 is surrounded by a sealing lip 27, which rests against the building wall when the device is in use.

[0015] The second housing part made of plastic has an outer wall 37 which, on its side facing away from the end wall 13, runs approximately on a circular arc line and is connected to the end wall 13 by essentially straight wall sections.

[0016] An inner wall 11 of the second housing part 2 is spaced radially from the outer wall 37 relative to a center point of the suction chamber 4 and is connected to the outer wall 37 by webs 38. Openings can be provided in the webs 38 into which fastening screws can be screwed, connecting the cover plate 10 to the housing. Cavities 39 are formed between the inner wall 11 and the outer wall 37.

[0017] The upper edge of the suction chamber 4 is surrounded by a circular rib, which forms a slanted flank 29 directed toward the suction chamber 4, which facilitates the insertion of an insert 30 into the suction chamber 4. The insert 30 can be used to reduce the effective area of ​​the suction chamber 4.

[0018] Figure 6 shows fastening means with which the first housing part 1 can be detachably connected to the second housing part 2. A web 26, which has two openings 20 spaced apart from one another, originates from the lower edge of the end wall 12. The corresponding lower region of the second housing part 2 has downwardly projecting pins 19 that can be inserted into the openings 20. Tabs 21 protrude from the upper edge of the end wall 13. These tabs each have a bore through which fastening screws 22 can penetrate. The corresponding regions of the end wall 12 form recesses 23 into which the tabs 21 can engage. The recesses 23 each have a base with a screw-in opening into which the threaded shaft of the fastening screw 22 can be inserted. can be screwed. Between the two recesses 23 is the half of the extraction nozzle 14 assigned to the first housing part.

[0019] The insert piece 30 shown in Figure 9 has a circular cylindrical shape. It has an outer wall 31 whose outer diameter corresponds to the inner diameter of the inner wall 11 of the second housing part 2. Within the outer wall 31, an inner wall 33 extends concentrically to the outer wall 31 and is connected to the outer wall 31 via a base. The inner side of the outer wall and the outer side of the inner wall are also connected to one another by webs 41, so that cavities 40 are formed. The inner wall 33 surrounds a suction chamber 4', which is connected to the flow channel 9 of the second housing part 2 by a flow channel 32. The flow channel 32 is delimited by two side walls 34, which connect the inner wall 33 to the outer wall 31.The flow channel 32 is delimited downwards by the base, so that this flow channel 32, like the flow channel 9, has a rectangular cross-section, although the flow channel 32 of the insert piece 30 is narrower than the flow channel 9 of the second housing part.

[0020] The cavities 40 and the flow channel 32 are closed at the top by a cover 35. The cover 35 is connected to two opposing webs 41 by screws. The cover 35 has a circular opening surrounded by an inner edge 35" of the cover 35, which is aligned with the inside of the inner wall 33. The outer edge 35' of the cover 35 also runs on an arcuate line and borders the inside of an upper edge region of the outer wall 31. An extension 36 protruding from the outer edge 35' closes the flow channel 32 at the top in the region of the outer wall 31.

[0021] Figures 10 and 11 show a second embodiment of a second housing part 2', which differs from the first housing part 2 essentially in the diameter of the circular suction chamber 4'. Here, too, the lower edge of the suction chamber 4' is surrounded by a sealing lip 27.

[0022] Figures 12 and 13 show a third embodiment of a second housing part 2". The suction chamber 4" is open on one side here. The second housing part 2" has two outer walls that protrude from the two edges of the end face 13, forming a fork. A base and a top side 25 each border the lower edge and the upper edge of the end wall 13, respectively, and form a peripheral edge running along a semicircle line, which delimits the open suction chamber 4" on one side. The flow channel 44 formed in this way is thus open to one broad side of the device and connected to the suction channel 8 on the opposite side.

[0023] Figure 14 shows an alternative fastening of the two housing parts to each other. Undercut ribs 45 protrude from one end wall 13 and can be inserted into dovetail grooves 46 in the other end wall 12. The ribs 45 and the grooves 46 extend vertically, with the opening 5 lying in a horizontal plane.

[0024] The device works as follows:

[0025] In a functional position, the two housing parts 1 and 2 are connected to each other. In this position, the two semicircular walls 15, 16 complement each other to form a truncated cone-shaped or cylindrical suction nozzle 14, onto which a suction hose 48 can be attached. The suction hose 48 is connected to a vacuum generator, for example to a Vacuum cleaner connected. This creates a negative pressure in the vacuum chamber 3 and an air flow through the flow channel 9, so that drilling debris can be sucked out of the suction chamber 4, 4', 4". By the partition wall 17, 18 extending into the walls 15, 16 of the suction nozzle by a distance that is preferably longer than the diameter of the suction nozzle 14, this prevents sucked-out drilling debris from passing through the suction channel 7 into the vacuum chamber 3. Openings (not shown) can also be provided, for example, in the housing wall surrounding the vacuum chamber 3, so that a permanent air flow is established in the suction channel 7.

[0026] The above statements serve to explain the inventions covered by the application as a whole, which each independently develop the state of the art by at least the following combinations of features, whereby two, several or all of these combinations of features can also be combined, namely:

[0027] A device which is characterized in that the wall of the suction nozzle 14 is formed by walls 15, 16 each formed in one of the housing parts.

[0028] A device which is characterized in that the two separable housing parts 1, 2, 2', 2" each form an end wall 12, 13, wherein the end walls 12, 13 abut one another and sections of the end walls 12, 13 extend into the suction nozzle 14 and there separate the suction channels 7, 8 from one another as partition walls 17, 18.

[0029] A device characterized in that semicircular walls 15, 16 of the housing parts 1, 2, 2', 2" complement each other to form a cylindrical or slightly conical suction nozzle 14 which is divided in the middle.

[0030] A device which is characterized in that the vacuum chamber 3 has an opening 5 which can be closed by placing it on a workpiece and which is surrounded by an edge 6 extending in a plane, the suction chamber 4 is open to the workpiece and has an upper side 25 extending substantially parallel to the plane, wherein an upper side 24 of the first housing part 1 is aligned with the upper side 25 and the suction nozzle 14 originates from the upper sides 24, 25.

[0031] A device which is characterized in that the second housing part 2, 2', 2" is connected to the first housing part 1 by means of fastening means 19, 20, 21, 22, 23 in a detachable manner and can be exchanged for another housing part 2, 2', 2", wherein it is provided in particular that another second housing part 2' forms a suction chamber 4 with a larger diameter or has a fork shape.

[0032] A device which is characterized in that the fastening means have pins 19 which engage in openings 20, wherein in particular it is provided that a web projects from the lower edge of an end wall 12, in which the openings 20 are arranged and / or that tabs 21 project from an end wall 13, which engage in particular in recesses 23 and which are connected to the bottoms of the recesses 23 by screws 22 and / or that the fastening means have a tongue and groove connection and in particular an undercut groove into which a dovetail tongue engages and / or at least one screw and / or pins 19 engaging in openings 20.

[0033] A device which is characterized in that the suction chamber 4 is fluidly connected to the suction channel 8 by a flow channel 9 originating from the inner wall 11 of the suction chamber 4, wherein it is provided in particular that the flow channel 9 is delimited by an upper housing wall, by two side walls 47 and by a lower cover plate 10.

[0034] A device which is characterized in that an insert piece 30 forming a suction chamber 4' with a reduced cross-section can be inserted into the suction chamber 4, which is preferably circular in cross-section, said insert piece having a flow channel 32 which is open to an inner wall 33' and an outer wall 31 of the insert piece 32.

[0035] A device which is characterized in that the second housing part 2' has a width which is greater than the width of the first housing part 1 or in that the second housing part 2" has a suction chamber 4" which is open towards the broad side of the second housing part 2".

[0036] All disclosed features are (individually, but also in combination with one another) essential to the invention. The disclosure of the application hereby fully incorporates the disclosure content of the associated / attached priority documents (copy of the prior application), also for the purpose of incorporating features of these documents into claims of the present application. The subclaims characterize, even without the features of a referenced claim, with their features independent inventive developments of the prior art, in particular for the purpose of filing divisional applications based on these claims. The invention specified in each claim may additionally comprise one or more of the features identified in the above description, in particular with reference numbers. and / or have the features specified in the list of reference numerals. The invention also relates to designs in which individual features mentioned in the above description are not implemented, in particular insofar as they are clearly unnecessary for the respective intended use or can be replaced by other technically equivalent means. List of reference symbols 1 first housing part 25 top 2 second housing part 26 web 2' second housing part 27 edge, sealing lip 2" second housing part 28 recess 3 Vacuum chamber 29 Inclined flank 4 suction chamber 30 insert 4' suction chamber 31 outer wall 4" suction chamber 32 flow channel 5 Opening 33 Inner wall 6 Edge, sealing lip 34 Side wall 7 first suction channel 35 cover 8 second suction channel 35' outer edge 9 Flow channel 35" inner rim 10 Cover plate 36 Extension 11 interior wall 37 exterior wall 12 front wall 38 web 13 Front wall 39 Cavity 14 suction nozzle 40 cavity 15 semicircular wall 41 bridge 16 semicircular wall 42 opening 17 Partition wall 43 Housing wall 18 Partition wall 44 Flow channel 19 tenon 45 rib 20 opening 46 dovetail groove 21 Tab 47 Side wall 22 Screw 48 Hose 23 Recess 24 Top

Claims

Claims 1. Device for extracting drilling debris produced during drilling, comprising a first housing part (1) having a vacuum chamber (3), wherein a first suction channel (7) fluidly connects the vacuum chamber (3) to a suction nozzle (14) having an outer wall (15, 16) and a partition wall (17, 18), and comprising a second housing part (2, 2', 2") having a suction chamber (4), wherein a second suction channel (8) fluidly connects the suction chamber (4) to the suction nozzle (14), characterized in that the outer wall of the suction nozzle (14) is formed by walls (15, 16) formed in each of the separable housing parts.

2. Device according to claim 1, characterized in that the two housing parts (1, 2, 2', 2')' each form an end wall (12, 13), wherein the end walls (12, 13) abut one another and sections of the end walls (12, 13) extend into the suction nozzle (14) and there separate the suction channels (7, 8) from one another as partition walls (17, 18).

3. Device according to claim 1 or 2, characterized in that each of the two housing parts forms a partition wall (17, 18), wherein the partition walls (17, 18) lie in contact with one another.

4. Device according to one of the preceding claims, characterized in that semicircular walls (15, 16) of the housing parts (1, 2, 2', 2')' complement each other to form a cylindrical or slightly conical suction nozzle (14) which is split in the middle and onto which a hose (48) can be plugged. Device according to one of the preceding claims, characterized in that the vacuum chamber (3) has an opening (5) which can be closed by placing it on a workpiece and which is surrounded by an edge (6) extending in a plane, the suction chamber (4) is open to the workpiece and has an upper side (25) extending substantially parallel to the plane, wherein an upper side (24) of the first housing part (1) is aligned with the upper side (25) and the suction nozzle (14) originates from the upper sides (24, 25). Device according to one of the preceding claims, characterized in that the second housing part (2, 2', 2") is connected to the first housing part (1) by means of fastening means (19, 20, 21, 22, 23) in a detachable manner and so as to be exchangeable for another housing part (2, 2', 2"), wherein it is provided in particular that another second housing part (2') forms a suction chamber (4) with a larger diameter or has a fork shape.Device according to claim 6, characterized in that the fastening means comprise pins (19) that engage in openings (20). Device according to claim 7, characterized in that a web, in which the openings (20) are arranged, projects from the lower edge of an end wall (12). Device according to one of claims 6 to 8, characterized in that tabs (21) project from an end wall (13), which tabs engage in recesses (23) and are fastened to the bottoms of the recesses (23) with screws (22). Device according to one of claims 6 to 9, characterized in that the fastening means have a tongue and groove connection and in particular an undercut groove into which a dovetail tongue engages. Device according to one of claims 7 to 10, characterized in that the fastening means have a screw or pins (19) engaging in openings (20). Device according to one of the preceding claims, characterized in that the suction chamber (4) is fluidly connected to the suction channel (8) by a flow channel (9) originating from the inner wall (11) of the suction chamber (4). Device according to one of the preceding claims, characterized in that the flow channel (9) is delimited by an upper housing wall, by two side walls (47), and by a lower cover plate (10).Device according to one of the preceding claims, characterized in that an insert piece (30) forming a suction chamber (4') with a reduced cross-section can be inserted into the suction chamber (4), which is preferably circular in cross-section and has a flow channel (32) open to an inner wall (33') and an outer wall (31) of the insert piece (32). Device according to one of the preceding claims, characterized in that the second housing part (2') has a width which is greater than the width of the first housing part (1) or that the second. Housing part (2") has a suction chamber (4") open to the broad side of the second housing part (2"). Device characterized by one or more of the characterizing features of one of the preceding claims.

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