Protective cover with a bellows and louvers attached to it

Description

[0001] According to the preamble of claim 1, the invention relates to a length-variable protective cover with at least one bellows element, in which a certain number of folds are designed as intermediate folds and the remaining folds as freely extendable folds, in that two adjacent layers of the bellows element are connected to one another to form the intermediate folds, wherein between these layers, in the intermediate folds designed as pockets, legs of L-shaped slats or of other support elements are fixed, wherein the legs have recesses which serve for fixing to the bellows element (see e.g. DE 20 2015 001696 U1).

[0002] For the protective function of a bellows, e.g. within machine tools, equipping it with lamellae, preferably made of steel, represents a significant improvement in mechanical resistance even in the toughest operating scenarios. These steel lamellas must be connected to the individual folds of the bellows body in such a way that the maximum extension and the block dimension of the bellows are affected as little as possible. Furthermore, the connection points themselves must not damage the bellows body during movement. The connection points should also not cause perforation of the bellows body so that the greatest possible tightness against the cooling lubricants used in the machine's working area is achieved. For the bellows to function correctly, it is also essential that the attached steel lamellas are pressed against each other with sufficient preload to prevent chips, etc. from getting behind the steel lamellas.

[0003] A variable-length protective cover of the type mentioned above is known from DE 10 2016 103 985 A1. This document describes an embodiment in which a lamella leg with an L-shaped recess is suspended in an intermediate fold of a bellows element from retaining elements arranged there that connect the fold layers. It is difficult to arrange the retaining elements in the intermediate layers, which is generally only possible with additional form-fitting elements, such as rivets, which pierce the bellows layers and thus impair their protective function against the penetration of liquid. The retaining elements also lead to an increase in the block dimensions.

[0004] Another protective cover is known from DE 10 2013 210 407 A1. In this case, all folds near the bend are riveted to the slats. This significantly limits the extension length relative to the minimum block length.

[0005] Finally, JP 2007-144534 A shows a protective cover in which the slats are connected and held in position by spring clips. A bellows is also provided, which is secured to the intermediate folds by rivets and separate retaining plates on both sides. This solution ensures excellent alignment of the slats, but also significantly increases the block length and the weight of the protective cover, which in turn impairs its dynamic behavior.

[0006] WO2019 / 215191 A1 shows a protective cover in which the overlapping slats are located on the side of the fold of the intermediate folds and are not inserted into the pockets from the open side.

[0007] The object of the present invention is to provide a protective cover which enables a secure connection of the lamellae to the bellows body with low dead weight and easy manufacture.

[0008] According to the invention, the object is achieved by a protective cover of the type mentioned at the outset, in which the two layers of the intermediate folds have connecting regions in which the two layers are materially connected to one another, and the legs of the slats or of the other supporting elements have recesses which have lateral openings which are so large that the legs can be inserted into the pockets, wherein the connecting regions reach into the recesses, wherein the edges of the recesses have at least partially hook-shaped or tooth-shaped structures which, in the mounted position, interact positively and / or non-positively with the edges of the connecting regions.

[0009] The inventive solution offers the advantage that the slats can be attached to the bellows via their legs without additional components. The integral connection of the slat layers in the connecting areas is preferably formed by welding the two layers before inserting the slats. With suitable plastic materials, it is preferable to integrally join the two layers of the intermediate fold in the connecting areas by means of ultrasonic welding or high-frequency welding, so that the connecting areas are designed as welds. These cannot be removed non-destructively. Alternatively, the layers can also be integrally joined in the connecting areas using adhesives.

[0010] With this type of fixing of the slats, the bellows itself no longer needs to be pierced, so that its protective function, for example against fluids escaping from the working area, is particularly well maintained.

[0011] When inserted, the hook- or tooth-shaped structures preferably engage indetachably with the material of the connecting areas in the manner of a barb, so that the legs are already permanently connected to the bellows element before the protective cover is installed.

[0012] Particularly advantageous is also the fact that the protective cover according to the invention can be manufactured more easily in an automated manner, because the step of manufacturing the connecting regions, for example by one of the welding processes mentioned, can also be carried out automatically, whereas the arrangement of metallic holding elements in the intermediate folds is problematic due to the unstable bellows structure.

[0013] The connecting areas can be designed so flat that the block dimensions of the compressed protective cover do not increase without any disadvantage in terms of function.

[0014] Typically, at least two, possibly more, connecting areas are provided per intermediate fold, whereby the leg to be mounted has a corresponding number of corresponding recesses.

[0015] In a preferred embodiment of the invention, it is provided that the legs of the slats are inserted through the open flanks of the pockets.

[0016] The open pockets allow the use of legs that extend practically across the entire width of the bag, resulting in a particularly good hold in the pockets with the connecting areas.

[0017] In order to enable a particularly good hold of the legs at the connecting areas, it is provided that a first hook-shaped or tooth-shaped structure is arranged on a first edge of the recess, wherein a second edge of the recess is arranged parallel to this edge and is smooth or has a further hook-shaped or tooth-shaped structure.

[0018] In order to facilitate the safe reaching of a defined end position of the legs in the pockets, it is provided that between the edges of the recesses one end of the recess is provided as a stop, which rests against the respective connecting area of ​​the two layers and defines the end position of the slat.

[0019] As an alternative to arranging the hook-shaped or tooth-shaped structure on the edge of a channel-like section of the recess with parallel edges, it can be provided that a first hook-shaped or tooth-shaped structure is arranged on a first edge of the recess, wherein opposite this edge there is arranged a further edge of the recess which is smooth or has a further hook-shaped or tooth-shaped structure, wherein the distance between the two edges decreases in the insertion direction of the leg.

[0020] With this variant, it is important to ensure that the exact insertion depth is achieved. The deeper the leg is inserted, the more deeply the hooks or prongs will grip the material of the connecting areas.

[0021] A particularly advantageous development of the invention provides that the recesses are L-shaped, wherein they have an insertion section running perpendicularly from the edge of the leg and a locking section running parallel to the leg, in which the hook- or tooth-shaped structures are provided.

[0022] The recesses and the connecting areas form a type of locking mechanism similar to a bayonet closure, whereby the legs can first be inserted into the pocket with almost no force and then moved parallel to their end position.

[0023] Advantageously, it is provided that at least one edge of the locking portion is formed with the hook-shaped or tooth-shaped structure, so that the anchoring of the legs to the bellows element can take place at this point.

[0024] A particularly preferred embodiment of the invention provides for the hooks or prongs of the hook- or prong-shaped structure to be elastically flexible. Such a design allows the hooks or prongs to deflect when the legs are inserted, thus placing less stress on the material of the connecting areas during insertion. In the extension direction, extension is difficult or impossible due to the increased extension forces resulting from the barb effect and / or a positive locking mechanism.

[0025] Accordingly, an embodiment of the invention may be preferred in which the hooks of the hook- or prong-like structure are designed as resilient barbs or spring tongues. Due to their resilient design, the hooks initially evade the connecting areas when the leg is inserted, but effectively block withdrawal because they stiffen when force is applied in the opposite direction and their tips dig into the material of the connecting areas. This allows for positive and / or force-locking holding forces to be generated.

[0026] The hooks of a recess can be arranged parallel to each other in a herringbone pattern.

[0027] A positive locking mechanism can be implemented, for example, in such a way that the hook-shaped or tooth-shaped structure has at least one movable hook element which, after insertion, snaps into a locking position or is movable into a locking position.

[0028] Elasticity can be achieved in a simple design, for example, by providing recesses in the legs in the area behind at least some of the hook- or prong-shaped structures, so that the edges of the recesses with the hook- or prong-shaped structures possess elastic flexibility. This, of course, requires certain elastic properties of the material used for the legs.

[0029] An example of a design with a positive locking mechanism is spring-loaded snap hooks that snap into corresponding undercuts.

[0030] Manually operated elements can be molded onto or attached to the leg, but it is also possible for the movable element to be designed separately from the leg and to be inserted into the pocket after the leg has been inserted. Regardless of their specific design, manually operated elements have the advantage that they can be designed in such a way that non-destructive disassembly is possible after they have been released. Even with purely spring-loaded elements according to the embodiments described above, it is possible, e.g. by using a suitable tool, to release the locking mechanism so that the corresponding slat can be removed from the pocket of the intermediate fold, e.g. if it is defective and needs to be replaced.

[0031] Typically, the legs are made of sheet steel, but they can also be made of suitable plastics, for example.

[0032] Among many other materials that can be used for bellows elements, thermoplastics such as polypropylene have proven particularly suitable for welding and other bellows materials. Examples worth mentioning here include bellows made entirely of one or more such thermoplastics, which can be multi-layered and / or reinforced, e.g., in the form of an embedded fabric structure.

[0033] A further particularly preferred embodiment of the invention provides that a single bellows as a bellows element extends over the entire length and width of the protective cover and forms the only connecting element of the slats to one another.

[0034] This variant consists of particularly few parts and the full-surface bellows protects the slats on the outside which are arranged inside towards a work area, e.g. a machine tool, and which are insensitive to mechanical influences, such as flying chips during the machining of workpieces.

[0035] However, bellows elements can also mean individual bellows elements that do not extend over the entire surface of the protective cover, such as bellows elements intended as extension limits.

[0036] Further features, details, and advantages of the invention will become apparent from the wording of the claims and from the exemplary embodiment described below with reference to the drawings. They show: Fig. 1 a view of a first embodiment of a protective cover for the working area of ​​a machine tool; Fig. 2 a detailed view of the bellows of the protective cover according to Fig. 1 without slats Fig. 3 a , b , c an assembly sequence of a lamella on the bellows; Fig. 4 an exemplary overview of possible further designs of the recesses.

[0037] In Fig. 1 A variable-length protective cover 10 is shown, such as is used in machine tools to shield work spaces in which, for example, metal workpieces are machined. The protective cover 10 adapts to the changing size, with a bellows element 12, which here is formed from a bellows extending over almost the entire variable surface of the protective cover 10.

[0038] For reinforcement, L-shaped steel slats 14 are provided on the side facing the work area. These are secured with legs 16 in intermediate folds 18 of the bellows 12, which will be discussed in more detail later. The slats 14 overlap each other in a scale-like manner with slat sections 19, thus forming a highly resilient, variable-length protection for the bellows 12 against chips, which can be very hot and have a considerable impact speed. Due to the scale-like overlap, adhering chips are scraped off by the edge of the adjacent slats during compression of the protective cover and cannot penetrate to the sensitive bellows.

[0039] Flange elements 20, 22 are provided at the two longitudinal ends of the protective cover, with which the protective cover 10 can be mounted on relatively movable parts of the machine tool (not shown). The overall shape shown is to be understood as an example, since the protective covers 10 can be individually adapted to the respective application. For example, L-shaped designs with two connected bellows arranged at a right angle are also possible.

[0040] Fig. 2 shows the bellows 10 in an enlarged detailed view without slats. The formation of pocket-like intermediate folds 18 between regular extension folds 26 is clearly visible. The intermediate folds 18 are formed by two layers 30, 32 of the bellows connected by a kink 28, which are secured to one another via a specific number of connecting areas 34. This does not represent a full-surface attachment of the layers 30, 32 to one another; rather, to achieve the pocket-like formation of the intermediate folds 18, only certain zones are to be connected to one another, between which gap-like free spaces 34 remain with an opening between the two layers 30, 32, into which the legs 16 of the slats can be inserted.

[0041] The connecting areas 34 of the exemplary embodiment presented here, with a bellows 12 made of polypropylene, are bonded together by ultrasonic welding, so that the material strength of the connecting areas corresponds to that of the bellows material. Ultrasonic welding can be used with any suitable plastic material for the bellows. Fabrics coated with weldable plastics can also be used.

[0042] In Fig. 3 a bis c The assembly of the slats 14 with their legs 16 in the pocket-shaped intermediate folds 18 is now explained, whereby for better illustration, the front layer 30 of the bellows 12 has been omitted from the illustrations and only the connection area on the rear layer 32 of the bellows 12 is shown. Fig. 3 a shows the leg 16 of the slat 14 with an L-shaped recess 36. The L-shaped recess 36 is divided into an insertion section 38 open towards the edge of the leg and an adjoining, right-angled locking section 40 which runs parallel to the longitudinal extent of the leg 16. An edge 42 facing the slat section 19 forms a first stop and extends to an end 44 of the locking section 40 designed as a stop. Adjoining this is an edge 46 which has a hook-like structure 48. The leg has recesses 50 in the area of ​​the hook-like structure 48, which ensure a certain elastic flexibility of the structure 48.

[0043] When mounting the legs 16 on the bellows 12, they are first positioned so that the connecting areas 34 of the associated intermediate fold 18 are aligned with the insertion sections (see Fig. 3a ). The leg 16 is then pushed into the pocket-shaped intermediate fold 18 until the connecting areas 34 are aligned with the edges 42 of the recesses 36. The leg 16 can then be moved parallel to its longitudinal extent, whereby the connecting areas 34 enter the locking sections 40 of the recesses 36 (see Fig. 3b ).

[0044] As from Fig. 3b As can be seen, the distance between the tips 52 of the hook-shaped structure 48 and the opposite edge 42 is selected to be somewhat smaller than the height of the connecting section 34. Upon insertion, the hook-shaped structure 48 yields slightly due to the intended elasticity, and the material in the connecting area 34 can also yield slightly. Due to the geometry of the hooks, the force required for insertion is considerably lower than in the opposite direction, so that the leg is permanently fixed to the connecting sections. Depending on the design, disassembly may be possible, possibly after mechanical intervention.

[0045] The end 42 of the locking section limits the insertion path and defines the Fig. 3c shown end position of the leg 16 in the intermediate fold 18.

[0046] In Fig. 4 A non-exhaustive selection of possible recesses is shown, which are suitable for locking on a correspondingly designed connection area. The recesses 36 a to d shown should not be combined on one leg, this serves in Fig. 4 For illustrative purposes only. In principle, however, different cutouts can be combined on one leg.

[0047] The recess 36a corresponds in Fig. 4 the previously described embodiment.

[0048] The recess 36b is also L-shaped, but hook-shaped structures 48b are provided on both edges 42b and 46b of the recess. No recesses are provided behind the hook-shaped structures.

[0049] The Fig. 4 The middle slat 14c shown shows a different locking concept, in which the recesses 36c and d have only one locking section 40c, d extending perpendicularly from the leg edge. The locking thus occurs here immediately upon insertion of the leg 16c into the intermediate fold 18. Hook-shaped structures 48c, d are arranged on one edge 42c, d of the locking section, the opposite edge 46c, d is arranged parallel thereto and has a smooth surface, the difference between the two variants being that in the recess 36c a recess 50c is provided behind the smooth edge 46c. The increased elasticity is thus provided here by the elastic, opposite edge 46c. This solution can also be transferred to the other embodiments.

[0050] Fig. 4 further shows a further embodiment of a slat 14e, the legs 16e of which again have L-shaped recesses 36e, each with an insertion section 38e and a locking section 40e. The illustration otherwise corresponds Fig. 3c , however, the connecting areas located in the recesses are not shown here. Due to the different orientation of the locking sections 40e, the insertion takes place in comparison to Fig. 3 a bis c also in the opposite direction.

[0051] The hook- or prong-shaped structures 48e are designed significantly differently, here featuring flexible spring tongues 54. These are arranged parallel to one another in a herringbone pattern, although this need not necessarily be the case. The spring tongues 54 are inherently so flexible and compliant that recesses behind the hook- or prong-shaped structures 48e can be completely omitted. When the leg is inserted over the connecting areas, the spring tongues yield slightly and offer only minimal resistance. However, when force is applied in the opposite direction, they stand up and engage the connecting areas in a form-fitting and / or force-fitting manner like barbs, also known as form-alignment locks. A very large lifting force would be required to release the leg after assembly on the bellows element.

[0052] The invention is not limited to one of the previously described embodiments, but can be modified in a variety of ways. For example, the hooks or prongs can be designed as elastic elements, alternatively or in addition to the recesses themselves. They can also be designed as snap hooks that snap into place behind the connecting areas 34, thus providing a locking mechanism. Locking elements independent of the legs can also be used, which are inserted to lock the legs only after the legs have been inserted into the pockets.

[0053] To improve elasticity, the recesses can be designed to cover a larger area than shown in the illustrations. For example, the hook- or tooth-shaped structures can be arranged on a web that is connected to the rest of the leg like a spring element.

[0054] Other bellows elements with appropriately designed connecting areas can also be connected with recesses in the legs, e.g., lockouts that can also connect individual adjacent slats. The legs can also be assigned to retaining elements or purely stiffening elements. Bezugszeichenliste

[0055] 10 Length-adjustable protective cover 12 Bellows element 14 Slats 16 Legs of the slats 18 Intermediate folds 19 Slat sections 20, 22 Flange elements 26 Extension fold 28 Bends of the intermediate folds 30, 32 Layers of the bellows 34 Connecting areas 35 Free spaces / pockets 36 L-shaped recesses 38 Insertion section 40 Locking section 42 Edge of the recess 44 End / stop of the recess 46 Edge of the recess 48 Hook- or tooth-like structure 50 Recesses 52 Tips of the hook-shaped structure 54 Spring tongues / barbs

Claims

1. A variable-length protective cover with at least one bellows element (12), in which a certain number of folds are formed as intermediate folds (18), in that in each case two adjacent layers (30, 32) of the bellows element (12) are connected to one another, wherein between these layers (30, 32), the intermediate folds (18) of L-shaped slats (14) are fixed in the intermediate folds (18) formed as pockets or by other support elements, wherein the legs (16) have recesses (36) which serve for fixing on the bellows element (12), characterized in that the two layers (30, 32) of the intermediate folds (18) have connecting regions in which the two layers (30, 32) are integrally bonded to one another, and the legs (16) of the slats (14) or of the other support elements have recesses (36) which have such large lateral openings that the legs (36) can be inserted into the pockets (35), wherein the connection regions (34) pass into the recesses (36), wherein at least part of the edges (42, 46) of the recesses (36) is provided with a hook-like or serrated structure (48) which interacts with the edges of the connection regions (34) in a form-fitting and / or force-fitting manner in the mounted position.

2. The variable-length protective cover according to claim 1, characterized in that the connection regions (36) are formed by welding points.

3. The variable-length protective cover according to claim 1 or 2, characterized in that the legs (36) of the slats (14) are inserted through the open flanks of the pockets (35).

4. The variable-length protective cover according to one of claims 1 to 3, characterized in that a first hook-like or serrated structure (48) is arranged on a first edge (42) of the recess, wherein this edge is arranged on a further edge (46) of the recess (36) oriented parallel to it, which is designed to be smooth or has a further hook-shaped or serrated structure.

5. The variable-length protective cover according to claim 4, characterized in that an end (44) of the recess is provided between the edges (42, 46) of the recesses (36) as a stop which rests against the respective connecting region (34) of the two layers (30, 32) and defines the end position of the slat (14).

6. The variable-length protective cover according to any of claims 1 to 3, characterized in that a first hook-like or serrated structure (48f) is arranged on a first edge of the recess (36f), wherein this edge is arranged opposite a further edge of the recess which is designed to be smooth or has a further hook-shaped or serrated structure, the distance between the two edges being reduced in the insertion direction of the leg (16f).

7. The variable-length protective cover according to any of the preceding claims, characterized in that the recesses (36) are L-shaped, wherein they have an insertion section (38) extending perpendicularly from the edge of the leg (16) and a locking section (40) extending parallel to the leg (16), in which the hook-like or serrated structures (48) are provided.

8. The variable-length protective cover according to claim 7, characterized in that at least one edge (42) of the locking portion (40) is formed with the hook-like or serrated structure (48).

9. The variable-length protective cover according to any of the preceding claims, characterized in that the hooks (54) or spikes of the hook-like or serrated structure are designed to be elastically flexible.

10. The variable-length protective cover according to claim 9, characterized in that the hooks of the hook-like or serrated structure are designed as resilient barbs (54).

11. The variable-length protective cover according to claim 9 or 10, characterized in that in the region behind at least a portion of the hook-like or serrated structures (48), recesses (50) are provided in the legs (16), so that the edges (42, 46) of the recesses (36) have an elastic resilience with the hook or serrated structures (48).

12. The variable-length protective cover according to any of the preceding claims, characterized in that the hook-like or serrated structure has at least one movable element which is snapped into a locking position after insertion or can be moved into a locking position.

13. The variable-length protective cover according to claim 11, characterized in that the movable element is formed separately from the leg and can be inserted into the pocket after the insertion of the leg.

14. The variable-length protective cover according to any of the preceding claims, characterized in that a single bellows (12) extends as a bellows element over the entire length and width of the protective cover (10) and forms the single connecting element of the slats (14) with one another.

15. The variable-length protective cover according to any of the preceding claims, characterized in that at least one bellows element is provided as a pull-out limitation.