DE8706335U1 - Filter element for a filter ceiling of a paint spray booth - Google Patents

Description

HOEGER, STELLR.E«QHt..&,pÄR7NER

PATENT ATTORNEYS UHLANDSTRASSE 14 c D 7000 STUTTGART t

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A 4 7 058 b Applicant: Dürr GmbH

b-201 Spitalwaldstrasse 18

5 Sept. 1986 7000 Stuttgart 40

Filter element for a filter ceiling of a paint spray booth

The invention relates to a filter element for a filter ceiling of a paint spray booth, which has a rectangular metal profile frame/the frame legs defining a passage opening have approximately horizontal support flanges that project into the interior of the frame, on which a rectangular grid rests, which supports a filter mat that, like the grid, extends over the passage opening, which is held down and clamped in the frame by clamping rails that are attached to the frame legs so that they can pivot about horizontal axes and can be pivoted down onto the filter mat.

The ceiling of the actual booth space of a paint spray booth is usually designed as a so-called filter ceiling across its entire width. It usually consists of rectangular filter elements, the circumference of which is formed by a frame, and the frames of adjacent filter elements are attached to one another using screw connections. The length of these rectangular filter elements usually corresponds approximately to the booth width, which can be 6 m, for example, while the width of the filter elements extending in the longitudinal direction of the booth is 1 m, for example.

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For example, from paint spraying systems created by the applicant, filter elements of the type mentioned above are known/ the frames of which are formed by galvanized steel profiles that have an approximately C-shaped cross-section, with the C opening towards the inside of the frame and having a lower leg that is approximately twice to three times as wide as its upper leg, which forms the flange that supports the grid and the filter mat. The grid is a galvanized steel wire grid, the edge areas of which are welded onto the flanges of the frame legs mentioned above. A support angle rail with an inverted L-shaped cross-section is welded onto the inside of the vertical back of each frame leg, to whose free longitudinal edge facing the inside of the frame a clamping rail is hinged in such a way that it can be pivoted about a horizontal axis running in the longitudinal direction of the relevant frame leg. This clamping rail is also a steel angle rail with an inverted L-shaped cross-section, which, when swung down, forms a channel with an inverted U-shaped cross-section with the support angle rail and, due to its own weight, clamps the filter mat between itself and the aforementioned flange of the relevant frame leg. In order to be able to swing the clamping rail up, a bow-shaped handle is welded onto the side facing the inside of the frame, which, when the clamping rail is swung up, rests against the vertical back of the frame leg in such a way that the clamping rail's center of gravity is in the direction of the

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The inside of the frame is next to the clamping rail pivot axis. Therefore, safety latches must be provided to prevent the clamping rails from accidentally falling down when changing the filter mats.

In addition to the high weight of these known filter elements, which makes their installation difficult, and the risk of accidents caused by the heavy clamping rails, the main problem with the known filter elements is that the filter mat can be damaged at the edges of the steel wire mesh by free wire ends, edges and burrs; these are also places where the fitter can injure himself when changing the filter mat. If the steel wire mesh is welded flush into the metal profile frame, the risk of injury is reduced, but this leads to a considerable increase in production effort and thus to a considerable increase in costs.

The invention was based on the object of creating a light and easy-to-manufacture filter element in which the grid supporting the filter mat can be easily attached without this grid posing a risk of damage to the filter mat.

Starting from a filter element of the type mentioned at the beginning, this object can be achieved according to the invention in that the frame legs are formed from extruded aluminum profile rails with recesses holding threaded elements and that clamping elements held down by the threaded elements are provided for clamping the grid between these and the flanges.

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The material for the frame legs will preferably be one of the usual aluminium alloys, but of course other light metal alloys that can be extruded are also possible. The recesses in the frame legs can be recessed T-slots into which slot nuts with threaded bolts are inserted; these threaded bolts can then protrude through openings in the grille so that the grille can be attached to the frame legs using washers and nuts. The frame legs could also have grooves into which the edges of the grille are pushed before it is attached so that they no longer pose a risk of injury. However, it is simpler to use tensioning strips that extend along the frame legs and are held down by the threaded elements to cover the edges or edges of the grille. It also helps to reduce the manufacturing effort if self-tapping screws in particular are used as threaded elements, which is easily possible with an aluminum profile rail, and in a preferred embodiment, longitudinal grooves are drawn into the frame legs as recesses for the threaded elements, into which the screws or the like can be easily screwed.

By using extruded aluminum profile rails for the frame legs, the weight of the filter element is drastically reduced and simple fastening options for the attachment of the grille are provided.

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and the clamping rails and the assembly of the metal profile frames to one another and to other parts, in particular by the fact that during extrusion grooves for slot nuts carrying threaded bolts and self-tapping screws are drawn into the aluminum profile rails. This applies in particular to the fastening of pivot bearings for the clamping rails, so that in a preferred embodiment each frame leg has a recessed longitudinal groove widening towards the base of the groove for holding slot nuts, to which supports for the clamping rails hinged to the latter, also designed as extruded aluminum profile rails, are fastened. In this way, not only is the welding of support angle rails unnecessary, as is the case with the known filter element described, but the use of extruded aluminum profile rails for the clamping rails further reduces the weight of the filter element, and the extruded clamping rails can be given almost any profile without increasing the manufacturing costs, which is why it is recommended to give the clamping rails a cross-section in the area against the filter mat that resembles a rounded hook that is open to the inside of the frame, in order to drastically reduce the risk of injury when replacing the filter mat, because instead of a relatively narrow edge on the heavy steel angle rail of the known filter element, there is a strongly rounded lower area of a light aluminum clamping rail of the filter element according to the invention . In addition, the handles, as they are present on the clamping rails of the known filter element,

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can be saved, since the aluminum clamping rails according to the invention form a gripping recess&eeegr; that can be grasped from the inside of the frame&pgr;.

Precisely because, for the reason described, there is relative freedom in the cross-sectional design of the extruded clamping rails, these can be designed in such a way that the pivot axis of the clamping rails has such a transverse distance from the relevant frame leg that the center of gravity of the clamping rail, which is pivoted up and rests against the associated frame leg, lies - in plan view - between the pivot axis and the frame disk, so that the safety latches for the clamping rails described in connection with the description of the known filter element can be omitted, which leads to further cost savings.

Further features, advantages and details of the invention emerge from the appended claims and/or from the following description and the appended drawings of several preferred embodiments of the filter element according to the invention;

show in the drawing:

Fig. 1: a vertical section through a spray booth perpendicular to the longitudinal direction of a paint spraying system 2ur explanation of the arrangement of a filter ceiling;

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Fig. 2: a longitudinal section through the spray booth according to line 2-2 in Fig. 1;

Fig. 3: the section "A" from Fig. 2 on a larger scale than in this figure, to illustrate a first particularly advantageous embodiment of the filter element according to the invention;

Fig. 4: a representation corresponding to Fig. 3 of a second embodiment of the filter element according to the invention;

Fig. 5: a representation corresponding to one half of Figures 3 and 4 of a third preferred embodiment of the filter element Sf according to the invention and

Fig. 6: a representation corresponding to Figure 4 of a fourth, particularly advantageous embodiment.

Figures 1 and 2 show a spray booth designated as a whole with 10, with side walls 12, a grating floor 14, over which vehicle bodies 16 are transported on rail-guided carriages in the longitudinal direction of the paint spraying system, a filter ceiling 20, which delimits a supply air chamber 24 provided with air inlet openings 22 at the bottom, an exhaust air washing device designated as a whole with 26 and an exhaust air chamber 28. The work space 30 of the spray booth 10 is evenly supplied with air flowing through the work space from top to bottom via the filter ceiling 20.

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Between individual sections of the spray booth 10 there are partition walls 36 which are provided with passage openings 35 for the bodies 16

As can be seen from Fig. 2, the filter ceiling 20 is composed of self-supporting filter elements 2OA, 2OB .... 2OG etc. arranged one behind the other in the longitudinal direction of the spray booth, which each extend over the entire width of the spray booth 10 and butt against one another in the longitudinal direction of the spray booth, whereby they are screwed together in a manner to be described in more detail.

The direction of air flow through the spray booth 10 is indicated by arrows in Figures 1 and 2.

In this respect, the spray booth corresponds to the state of the art.

In the following, the first embodiment shown in Figure 3 of the metal profile frame designated as a whole with 40 in Figures 1 and 2 will be explained in more detail.

This is composed of four frame legs 42 that abut against each other at right angles and are obtained by cutting an extruded aluminum profile rail to length. According to the invention, this profile rail has a box-shaped hollow profile 42a with a molded-on lower support flange 42b. The latter advantageously has an approximately W-shaped profile with a longitudinal groove 42d drawn into a central web 42c. Furthermore, a T-groove 42g is drawn into the aluminum profile rail to form an inner web 42e.

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Finally,

Two longitudinal grooves 42i with a semicircular cross-section are drawn into the surface of the aluminum profile rail that forms the outside of the frame, in order to be able to insert sealing cord 44 between the frame legs 42 of adjacent filter elements 2OF and 2OG.

According to the invention, adjacent filter elements can be fastened to one another via a transverse connecting rail and screws which are screwed into a longitudinal groove which is drawn into the aluminum profile rail ^and are expediently designed as self-tapping screws.

A galvanized steel wire mesh 50 is placed on the supporting flanges 42b of the four frame legs 4 2 of a metal profile frame 40, whereby it is recommended that the

Edge areas 50a of the grid 50 are to be bent downwards and *

into an upwardly open groove 42k, which is formed by the t

respective support flange 4 2b is formed. Then ';

the edges of the grid 50 four clamping strips 52 are placed '

and secured with screws 54, which are the same

if self-tapping screws are used, ^: j

can be easily screwed into the longitudinal grooves 42d; on \

In this way, the steel wire mesh 50 can be positioned between &iacgr;

the four support flanges 42b and the four clamping strips 52 i

After the configuration shown in Figure 3,

guide form the edge regions 50a of the grid 50 from the &iacgr;

Grooves 4 2k of the frame legs 42 shielded |

it would not be necessary to change the grid J

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edges with the clamping strips 52, so that in this embodiment it would also be possible to provide only simple washers or the like for the screws 54 instead of the clamping strips 52 in order to securely fasten the grille 50 to the support flanges 42b.

Finally, a filter mat 58, possibly made up of several parts, is placed on the grid 50, which according to the invention extends at least almost to the inner side wall of the hollow profile 42a of all four frame legs 42 and is preferably held on each side of the metal profile frame 40 by a clamping rail 60, which according to the invention is designed as an extruded aluminum profile rail and can be pivoted up from its effective position shown in Fig. 3 in the direction of arrow B about a joint 62 in order to replace the filter mat 58. According to the invention, the clamping rail 60 has a cross section in the form of a strongly rounded hook. It is held by a support rail 64, which is advantageously U-shaped in cross section, to which the joint 62 and sliding blocks 66 are attached, the latter being able to be pushed into the T-slot 42g before the frame legs 42 are joined together to form the frame 40. According to the invention, the clamping rail 60 is designed in such a way that its center of gravity lies between the joint 62 and the hollow profile 42a (seen in plan view) when the clamping rail, after being swiveled up, assumes its ineffective position shown in dash-dotted lines on the left in Figure 3. When swiveled down, however, it clamps the filter mat between itself and the relevant clamping bar 52.

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The embodiment shown in Fig. 4 will now only be described insofar as it differs from the first embodiment shown in Fig. 1, the same reference numerals being used for corresponding parts, but with the addition of a prime to the elements of the embodiment according to Fig. 4.

In this embodiment, the clamping strip 52' has the shape of an angle rail according to the invention, and its cross section forms an obtuse angle. It rests (as in the embodiment according to Fig. 3) with its longitudinal edge facing the hollow profile 42a* on a sealing cord 70' which is inserted into a recessed groove in the aluminum profile rail. Since the clamping strip 52' also covers an edge region 50a' of the steel wire mesh 50' in this embodiment, the edge region ^50a1 was bent upwards in this embodiment. Threaded bolts 48' extending through these frame legs are used to fasten abutting frame legs 42* of adjacent metal profile frames 40' to one another.

The third embodiment shown in Fig. 5 also only requires an explanation insofar as it should be pointed out that the same reference numerals as in Fig. 3 have been used for the elements corresponding to the embodiment according to Fig. 1, but with the addition of two dashes. Fig. 5 shows that the aluminum profile rails forming the frame legs 4 2"

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Longitudinal grooves 42h" can be inserted at almost any location where they are useful for attaching the filter elements to other components of the spray booth .

Finally, it should be mentioned that on the inside of the hollow profiles 42a or 42a* or 42a" any desired retaining grooves can be formed on the hollow profile walls during extrusion, which serve to hold stiffening strips 80 or 80* or 80" - the latter can be sheet steel strips which are inserted into the frame legs 42 or 42' or 42" before the frame 40 or 40* or 40" is assembled.

The particularly advantageous embodiment according to Figure 5 is also only described to the extent that it requires explanation according to the above statements.

In this embodiment, the steel wire mesh 150 is not only covered and held down by means of a tensioning bar 152, but a tensioning tab 153 fastened to the frame leg 142 with the same screws 154 that are also used to fasten the tensioning bar 152 serves to tension the edges of the mesh outwards. For this purpose, the tensioning tab 153 engages behind a wire of the mesh 150 that runs perpendicular to the plane of the drawing with a hook-shaped bent edge 153a.

According to the invention, the profile rails forming the frame legs 142 together with the clamping strips 152 form a longitudinal channel 155 into which an elastic seal is inserted into which the wires of the grid 150,

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which passes through the channel 155. Since the seal 157 is located on the inner edge of the gap formed by the support flange 142b of the frame leg and the clamping bar 152 for receiving the grid 150, the seal can prevent dust that would otherwise collect in this gap from falling into the interior of the spray booth.

As can be clearly seen from the upper position of the clamping rail 160 shown in dash-dotted lines, its back forms an inclined surface 163 which facilitates the insertion of the filter mat 158 into the frame.

It is also advantageous that the upwardly pivoted clamping rail 160 ends below an upper step surface 142a, which is formed by the frame legs 142, so that a fitter who has to replace the filter mat 158 can comfortably walk on the frame by means of the step surfaces 142a.

Finally, according to the invention, in this embodiment too, the jpannleiste 152 forms a support angle for the filter mat 158.

A particular advantage of the filter elements according to the invention is that screws are used to fasten the steel wire grids, but they do not protrude into the interior of the spray booth, not even with their screw heads.

Claims (10)

HOEGER ₁ STELLREjClHt ^: &. PARTNER PAT &Egr;*&Ggr;«·&Tgr; A*NWWL ¹ + ' E "' UHLANDSTRASSE 14 c - D 70&Ogr;0 STUTTGART 1 A 47 053 b Applicant: Dürr GmbH b-201 Spitalwaldstrasse 5 Sept. 1986 7000 Stuttgart EXPECTATIONS 1. Filter element for a filter ceiling of a paint spray booth, which has a rectangular metal profile frame, the frame legs defining a passage opening having approximately horizontal support flanges projecting into the interior of the frame, on which a rectangular grid rests, which supports a filter mat that, like the grid, extends over the passage opening, which is held down and clamped in the frame by clamping rails that are pivotably attached to the frame legs about horizontal axes and can be pivoted down onto the filter mat, characterized in that the frame legs (42) are formed by extruded aluminum profile rails (42a, 42b) with recesses (42d) holding threaded elements (54), and that clamping elements (52) held down by the threaded elements are provided for clamping the grid (50) between these clamping elements and the flanges (42b). 2, Filter element according to claim 1, characterized in that the clamping elements are designed as clamping strips (52) held down by the threaded elements (54), extending along the frame legs (42) and covering the edges (50a) of the grid (50). -2- A 47 058 b 5 Sept. 1986 -2- 3. Filter element according to claim 1 or 2, characterized in that the threaded elements are in particular self-tapping screws (54). 4. Filter element according to one or more of claims 1 to 3, characterized in that each rail leg (42) has a recessed longitudinal groove (42d) forming the recesses for the threaded elements (54). 5. Filter element according to one or more of claims 1 to 4, characterized in that each frame leg (42) has a recessed longitudinal groove (42g) widening towards the groove base for holding sliding blocks (66), on which supports (64) for the clamping rails hinged to the latter, also designed as extruded aluminum profile rails (60) are attached. 6. Filter element according to claim 5, characterized in that the clamping rails (60) have a cross-section in their area against the filter mat (58) which resembles a rounded hook that is open towards the inside of the frame. 7. Filter element according to claim 5 or 6, characterized in that the pivot axis (62) of the clamping rails (60) has such a transverse distance from the relevant frame leg (42) that the center of gravity of the pivoted-up clamping rails (60) against the associated frame leg -3- A 47 058 b 5 Sept. 1986 -3- adjacent clamping rail - in plan view between the pivot axis and the frame leg. 8. Filter element according to one or more of claims 2 to 7, characterized in that the filter mat (58) is clamped between the clamping strips (52) and the clamping rails (60). 9. Filter element according to one or more of the preceding claims, characterized in that the clamping rails (160) are dimensioned and their pivoting axes (62) are arranged in such a way that the frame legs (142) protrude upwards beyond the pivoted clamping rails and form a step surface (142a) at the top for walking on the frame (40). 10. Filter element according to one or more of the preceding claims, characterized in that the surface (163) of the upwardly pivoted clamping rail (160) facing the interior of the frame is inclined downwards and inwards. -A-