SPOUT

Description

[0001] The invention relates to a grommet made of a material which is at least partially elastic for receiving at least one elongated object, in particular a cable, for strain relief and sealing according to the type defined in more detail in the preamble of claim 1.

[0002] Such grommets, which can be opened laterally via a slot in order to accommodate pre-assembled cables, hoses, pipes, lines or the like, are generally known with the corresponding perforations for accommodating the elongated objects. Pre-assembled means that the elongated objects are provided with attachments that protrude beyond the diameter of the elongated objects, e.g. connectors for cables or flanges for pipes. Purely as an example in this context, reference can be made to the applicant's German patent DE 10 2009 060 988 B3, which shows such grommets for strain relief in a cable support unit. In addition, other grommets with membranes are shown which are not slotted and which are designed to be pierced by cables in order to thus ensure a seal.

[0003] The generic prior art is described in EP 0 514 174 A1. This shows a grommet made of elastic material, which is slotted and designed to accommodate two cables. It features three consecutive membranes in the longitudinal direction of the cable or, where appropriate, other elongated objects. These membranes are relatively thin compared to the outer material of the frame element of the grommet in the longitudinal direction of the cable to be accommodated, in order to accommodate cables of different diameters, as described in the document.

[0004] In practice, this structure with the three membranes has proven relatively complex to manufacture and relatively large in terms of its length in the longitudinal direction of the cable to be accommodated. Furthermore, the seal often cannot be guaranteed with sufficient quality, as the cables tend to tilt laterally within the membranes, and the elastic material of the membranes completely surrounding them thus impairs the seal through protrusions or bulges. The document attempts to mitigate this to a certain extent by using three membranes arranged in series, but this comes at the cost of an extremely large overall length in the longitudinal direction of the inserted cables.

[0005] As already mentioned, the risk of lateral jamming can be reduced by using a larger number of membranes, each with equally sized holes. Even if this is successful, it remains a disadvantage that the membrane is designed to surround the entire cable. In order to ensure sufficient elasticity for cables of different sizes, this leads in practice to insufficient strain relief and, especially with large cable diameters, also to a lack of tightness, despite the three membranes arranged one behind the other, because the membrane material bends very easily in the longitudinal direction of the cable, which adversely affects both the strain relief and the tightness.

[0006] Reference can also be made to EP 1 498 994 A2. This shows a hinged cable grommet with a membrane offset into the interior of the grommet in the direction of the cable. This membrane has asymmetrical perforation. DE 103 49 996 A1 shows a similar structure, although here the membrane delimits the grommet in one direction along the length of the cable to be accommodated.

[0007] Further prior art includes FR 2 825 841 A1, which shows the fastening of cables in a split structure using individual clamps. US 4 889 298 A shows a house entry for cables routed through a house wall. Sealing is achieved by rubber blocks, arranged both inside the wall and at a distance from them outside the wall. DE 697 07 645 T2 describes a cable receptacle with a compression spring. DE 11 2010 005 160 B4 shows a cable grommet with a silencer.

[0008] Document WO 95 / 15603 A1 describes a device for enclosing elongated objects. Essentially, it describes a housing that is closed at each of its two spaced-apart ends by a grommet. This grommet has an integrated metallic reinforcement and can be opened laterally to insert the elongated object or cable. Around the grommet's through-opening, individual areas of low elasticity and other areas of higher elasticity are arranged, alternating over the entire circumference. The multitude of alternating zones of varying elasticity around the opening diameter is intended to achieve both good sealing and good strain relief.

[0009] The object of the present invention is to provide an improved grommet which ensures very good sealing and good strain relief even when the diameters of the inserted elongated objects differ considerably.

[0010] According to the invention, this object is achieved by a grommet having the features in claim 1, and here in particular in the characterizing part of claim 1.

[0011] The grommet itself consists of an outer frame element that can be folded open. This frame element can be made of an elastic material, as in the prior art. In principle, it would also be conceivable to construct the frame element, for example, from a less elastic plastic, which is held together on one side by a film hinge or a similar flexible connecting element and can be folded open accordingly. The frame element is then provided with at least two membranes spaced apart in the longitudinal direction of the elongated object to be accommodated, which membranes are aligned with one another and each have a perforation of the same size for receiving the elongated object, as is also the case in the above-mentioned EP specification from the American Telephone and Telegraph Company.

[0012] According to the invention, however, it is now provided that the respective perforation of the at least two membranes touches the material of the frame element on the side of the slot, i.e. on the side on which the frame element can be folded open. This contact between the perforation and the frame element on the side of the slot creates the possibility of various elongated objects of different diameters being able to be accommodated very well, and this with very good sealing on the one hand and sufficient strain relief on the other. The adaptation with regard to the different diameters of the elongated objects therefore always takes place in the area of ​​the at least two membranes, since the elongated object rests against the closed frame element in the perforation on the other side.The frame element thus reliably defines its position on one side, so that the majority of the diameter difference can be absorbed by the at least two membranes with regard to sealing and strain relief. Furthermore, the design offers the advantage that the spatial size of the membrane surface is maximized for the specified design, since the perforation and the subsequently accommodated elongated object are positioned on the frame element on one side, and the entire free space within the frame element on the other side is filled by the then relatively large-area membranes. This contributes to the advantageous effectiveness of the design.

[0013] The grommet can be designed for one elongated object in one pair of perforations, or for several elongated objects in each pair of perforations. The membranes with the perforations would then have a slit for each pair of perforations, so that, for example - as in the prior art - one pair of perforations would be provided with a slit to the right and one pair of perforations with a slit to the left. To accommodate four elongated objects, this would then involve two pairs of perforations arranged one above the other, each opening to the right, and two pairs of perforations arranged one above the other, each opening to the left via the slit. Of course, it would also be conceivable for the slits to run not only to the right and left, but also up and down.

[0014] As already mentioned, the frame element and the membrane can be constructed in multiple parts, for example a frame element made of relatively rigid plastic which can be folded using a film hinge or similar, and to which the membranes, for example two membranes, can be injection-molded on the respective side surfaces in the longitudinal direction of the elongated object to be accommodated. However, according to an advantageous development of the idea, the frame element and the membranes can also be made of the same material. This is very simple and efficient in terms of production. The different properties with regard to the elasticity of the membranes on the one hand and the frame element on the other hand, which should certainly be elastic but not as soft as the membranes, can then be easily achieved by different wall thicknesses of the material in the longitudinal direction of the elongated object to be accommodated.With this design, it is also conceivable for the membranes and the frame element to be formed as a single piece. However, this need not be the case. The frame element and the membranes can, for example, also be split centrally in the longitudinal direction of the elongated object to be accommodated, so that each sub-element, for example, comprises one of the membranes. If the sub-elements are then connected to one another, for example, welded or glued, the grommet according to the invention is created with the advantageous properties described above.

[0015] In the grommet according to the invention, it is now provided that at least one, preferably all, of the membranes have three zones of different elasticity over the circumference of the perforations.

[0016] Such a structure of the membrane(s), with zones of varying elasticity, allows the membrane to be ideally adapted to its specific task during construction. The zones of varying elasticity allow the areas that typically experience greater deformation to be designed with greater elasticity, ensuring excellent sealing. At the same time, areas that experience somewhat less deformation can be designed with less elasticity to improve strain relief there.

[0017] According to the invention, the middle zone, arranged transversely to the longitudinal direction of the elongated object to be accommodated, between the other zones, has a higher elasticity than the two adjacent zones. If the frame element itself is considered an additional zone, this would be a zone with even lower elasticity than the zones within the membrane, just for the sake of completeness. The described structure, with the zone of highest elasticity in the middle, enables ideal deflection in this area, while simultaneously ensuring a firm grip of the adjacent zones around the circumference of the elongated object. This ensures both good sealing and good strain relief.

[0018] According to a very advantageous development of the concept, exactly two membranes can be provided in each case. Such a structure with two membranes is sufficient for adequate sealing and strain relief in the design used, in which the respective perforation of the membrane touches the material of the frame element on the side of the slot. The use of two membranes in the longitudinal direction of the elongated object to be accommodated, and thus a space between these membranes, enables a compact design of the grommet in the longitudinal direction of the elongated object to be accommodated, thus allowing it to be implemented in a space-saving manner.

[0019] A particularly advantageous development of the grommet according to the invention further provides for the frame element to have a recess in the area where the perforations contact each other. This displaces the perforation, and thus the elongated object to be accommodated in the perforations, even further toward the frame element, further increasing the size of the membranes and thus enabling high flexibility when sealing different diameters. The material of the membranes can thus ideally adapt and seal well to elongated objects of various diameters, providing both sealing and strain relief.

[0020] According to a very advantageous embodiment, the respective perforation in the area of ​​each cross-section perpendicular to the longitudinal direction of the elongated object to be accommodated touches the frame element at the point at which the ends of the slot facing the perforation are located. The perforation therefore only touches the slot at one point. The perforations and the frame element therefore do not overlap in the area of ​​the slot, regardless of its course in the longitudinal direction. In particular in the case of a slot that runs linearly in the longitudinal direction, it can preferably be the case that the perforations touch the frame element in the area of ​​the slot along a line perpendicular to a tangent at the point of contact between the perforation and the pressed and thus largely linear slot.Such contact is ideal because the elongated object then only contacts the frame element along such a line, especially a straight one, which ultimately allows for minimal contact with the frame element and contact with the membrane over most of the elongated object's circumference. This further supports good sealing and strain relief.

[0021] Since the inserted elongated objects, such as cables, pipes, hoses, or the like, typically have a round cross-section, a very advantageous development of the concept can provide for the recess in the frame element to be circularly segmented in cross-section. Such a circular segment-shaped recess opens up the possibility of the elongated object also resting against the frame, which, on the one hand, prevents jamming and, on the other hand, optimizes sealing and strain relief.

[0022] According to a further very advantageous embodiment of the idea, it can be provided that the circular segment has a larger diameter than the perforation. This design enables an elongated object with a relatively small diameter to be accommodated, so that despite the circular segment-shaped recess, the object rests tangentially against the material of the frame element, in particular along a straight slot, and yet the recess allows for a relatively large surface area for the membrane. As the diameter increases, the contact of the elongated object then increasingly approaches a direct contact with the frame, with minimal remnants of the membrane remaining above and below the tangential contact area in order to safely and reliably accommodate and seal different diameters in this area too.

[0023] Regarding the manufacture of the membrane, it is conceivable in principle to achieve this by using a different structure and different materials for the membrane. However, according to an extremely advantageous and advantageous development of this idea, the zones of different elasticity can have different membrane thicknesses. This allows the construction of at least the membrane from a single material to be realized simply and efficiently. The different elasticities can be achieved simply by using different membrane thicknesses during production, for example, through an injection molding process or the like. This also allows for complex shapes for the individual zones of different elasticity, which can be manufactured very easily in this way.

[0024] According to a very advantageous development of the concept, the zones can be provided with straight boundaries starting from the perforation. These straight boundaries are particularly simple and efficient to manufacture, especially in the production of corresponding molds for producing the membranes or grommets, for example, in an injection molding process.

[0025] A very advantageous development of this idea provides for extensions of the zone boundaries to intersect at the point where the perforation is attached to the frame element. Starting from this point, the straight boundaries of the zones are realized. This results in a structure in which different zones prevail over the circumference of each of the perforations, so that not only the membrane as a whole, but also, in particular, the part of the membrane that lies directly against the elongated object, which is accommodated in the perforation, exhibits different elasticities. As an alternative to such a straight design, the use of curved boundaries or any other desired boundaries between the individual zones is of course also conceivable in principle.

[0026] In practice, it has been found that three zones with two different degrees of elasticity are ideal as a good compromise between manufacturing effort on the one hand and functionality on the other. According to a very advantageous development of the inventive grommet with zones of different elasticity, it is provided that there are three zones with two different degrees of elasticity, with the middle zone, arranged transversely to the longitudinal direction of the elongated object to be accommodated, having a higher elasticity than the two adjacent zones.

[0027] A very advantageous development of the grommet according to the invention can further provide that the two or both outer membranes are arranged offset inwards in the longitudinal direction of the elongated object to be accommodated relative to the outer boundary of the grommet. Thus, according to the invention, the grommet can be designed, for example, in the manner of a cuboid, a cube, a cylinder, or the like. The advantageous development described here offsets the structure of the membranes inwards relative to the outer surfaces of such a cube or cuboid, so that, for example, the two membranes, or if more than one membrane is present, the two outer membranes, are arranged offset inwards relative to the outer surface of the cuboid.If the grommet is accommodated, for example, in a cable entry such as the frame or similar device described in the applicant's German patent cited above, or even in a housing, the grommets often interact with the housing or frame in a form-fitting manner, typically in the central region in the longitudinal direction of the elongated object to be accommodated, so that greater forces can act on a membrane set back from the longitudinally outer surface than on a membrane arranged directly on the outer surface. The membranes set back from the outer surface, or outer membranes, depending on the total number of membranes, therefore have the advantage of allowing greater forces to compress the membranes and thus ultimately greater forces for sealing and strain relief.

[0028] The slot in the frame element can, in principle, be implemented in any desired manner. For example, the two documents mentioned above disclose linear slots and wave-shaped slots. However, according to a particularly advantageous refinement of the concept, the slot can have at least one, particularly trapezoidal, step in the longitudinal direction of the elongated object to be accommodated. This enables good interlocking of the surfaces forming the slot. This applies in particular in combination with curved or linear sections of the slot, preferably with linear sections of the slot in the region of the membranes / perforations.

[0029] According to an advantageous development, this can be further improved by providing the parts of the frame element in the region of the slot with at least one guide element on one part and at least one corresponding opening on the other part. This improves the precise positioning of the parts relative to one another. The guide element is in particular formed integrally with the frame element.

[0030] Another refinement provides, alternatively or particularly additionally, that the slot has at least one step transverse to the longitudinal direction of the elongated object to be accommodated. While this extends the surface to be sealed, it can, similar to the guide elements, help improve the positioning of the parts of the frame element relative to one another.

[0031] Further advantageous embodiments of the grommet according to the invention also emerge from the exemplary embodiments which are described in more detail below with reference to the figures.

[0032] Showing: Fig. 1 is a three-dimensional view of a possible embodiment of a spout according to the invention; Fig. 2 is a side view of the spout looking in the longitudinal direction of the elongated object to be received; Fig. 3 is a plan view of the spout; Fig. 4 is a first possible embodiment of the spout in a section along the line BB in Fig. 2 ; Fig. 5 another possible embodiment of the spout in a section along the line BB in Fig. 2 ; Fig. 6 a third possible embodiment of the spout in a section along the line BB in Fig. 2 ; Fig. 7 the design of the grommet according to Fig. 6 in a section along the line AA in Fig. 3; Fig. 8 a section of the nozzle or its membrane in a section along the line CC in Fig. 7 ; Fig. 9 shows a further embodiment of the grommet according to the invention in a section along the line AA in Fig. 3 ; Fig. 10 shows a further embodiment of the grommet according to the invention in a section along the line BB in Fig. 2 ; Fig. 11 the design of the grommet according to Fig. 10 in a section along the line AA in Fig. 3 ; Fig. 12 another alternative embodiment of the spout in a section along the line BB in Fig. 2 ; Fig. 13 the design of the grommet according to Fig. 12 in a section along the line AA in Fig. 3; Fig. 14 a three-dimensional view of an alternative embodiment of the grommet; Fig. 15 a possible embodiment of the slot in a variant of the grommet; Fig. 16 a possible detail of the slot, which can be realized for different shapes of the slot; Fig. 17 another possible variant of the slot, which can be combined with the other variants; and Fig. 18 an exemplary application of the grommets according to the invention.

[0033] In the presentation of the Figure 1 A schematic representation of a grommet 1 in a possible embodiment according to the invention can be seen. In the embodiment shown here, the grommet 1 is intended to be formed in one piece and from a single material, for example an elastic polymer. The grommet 1 can be opened in a manner known per se via a slot 2 in order to insert an elongated object, such as a cable 5, which in the illustration of the Figure 4 shown. By connecting the hole 3 with the slot 2, a pre-assembled cable 5, i.e. one which, for example, already has a plug or the like, can also be easily inserted into the grommet 1 because it is not threaded through the hole 3, but can be inserted laterally by folding it open along the slot 1. The grommet is then folded back over the elongated object or the cable 5 and pressed, for example, into corresponding receptacles in a housing, a frame or the like, in order to hold the cable 5 securely, i.e. to ensure strain relief in the longitudinal direction L and to seal the feedthrough of the cable through the hole 3 or the grommet 1.

[0034] In the Figure 2It can be seen that the perforation 3 has a first diameter. A second diameter is indicated by a dashed line. The structure is now realized in such a way that elongated objects, in particular cables 5, with different diameters, in particular with diameters between the diameter range of the perforation 3 or a minimally larger diameter on the one hand and the diameter shown here in dashed lines on the other hand, can be securely and reliably accommodated in the grommet 1 in a strain-relieving and sealed manner.

[0035] In the presentation of the Figure 3 A top view of the grommet 1 is shown, primarily to clarify the position of subsequent sectional views via line AA. Accordingly, Figure 2 a line BB is drawn.

[0036] In the presentation of the Figure 4 It can now be seen that when looking at a section along the line BB from Figure 2the structure of the grommet 1 is such that on the one hand it has a frame element 4, from which the Figure 4 the side shown on the right is cut and the Figure 4 The side shown on the left can be seen along the slot 2. In the longitudinal direction L of the cable or elongated object shown here and designated 5, there are two membranes 6 spaced apart from each other, which as such have a higher elasticity than the frame element 4, for example in a one-piece construction or a construction made of the same material of the frame element 4 and the membranes 6 due to a different material thickness, in particular in the longitudinal direction L of the cable 5 to be accommodated. The cable 5 can now be accommodated in the grommet 1 through the two membranes 6. Cables 5 of different diameters can also be accommodated without any problem. Here, analogous to the illustration in Figure 2a cable 5 with a slightly larger diameter than the perforation 3 is indicated. A thicker cable 5 is also shown in dashed lines, which can also be accommodated in the grommet 1 in a sealing and strain-relieving manner. Depending on the size of the grommet 1, the range is a few millimeters, for example, for a grommet 1 with a width and / or height transverse to the longitudinal direction L in the order of 15 to 25 mm. With correspondingly larger grommets, larger differences between the minimum diameter of the cable 5 that can be accommodated and its maximum diameter are also conceivable.

[0037] An alternative embodiment, which has already been indicated at the beginning of the description, can be found in the representation of the Figure 5. Unlike previous designs, the frame element 4 is made of a harder plastic material, in particular a fiber-reinforced plastic. The two-part frame element with the slot 2 on one side can be opened via a film hinge 7. Now, in the closed state, the top and bottom of the illustration show the Figure 5 A membrane 6 is attached, for example, by injection molding. The elastic membrane 6 then fulfills the described functionality, comparable to the above embodiments, and also allows the frame element 4 to be opened via the film hinge to a certain extent, which is sufficient to insert pre-assembled cables into the holes 3 via the slot 2.

[0038] In the presentation of the Figure 6 is another section along line BB from Fig. 2 In this variant it can be seen that the membrane 6 in the Figure 7 , a sectional view along the line AA in Fig. 3 The same structure has different wall thicknesses, which will be discussed below. Furthermore, it can be seen that the frame element 4 and the perforation 3 are designed in such a way that through the perforation 3 in the frame element 4 in the illustration of the Figure 6 on the left side a recess 8 is created. The hole therefore does not only touch the frame element 4, as shown in the illustrations of the Figures 2, 4 and 5 , but protrudes slightly into the frame element 4. The recess 8 thus ultimately enables an even larger surface area of ​​the membranes 6 on the one hand and enables a very good attachment of the elongated object or cable 5 to be accommodated to the frame element 4 in the region of the slot 2 on the other.

[0039] The already mentioned different thicknesses of the material of the membranes 6 can now be seen in particular in the illustrations in the Figures 7 and 8explain in more detail. The sectional view along line AA in Fig. 2 in the representation of the Figure 7 shows the perforation 3 in the membrane 6 and in the recess 8 in the frame element 4. In addition, the membrane 6 itself is divided into three different zones 6a, 6b and 6c. The boundaries between these zones 6a, 6b, 6c of the membrane 6 are straight in this embodiment and, if they were extended into the perforation 3, would intersect at the point where the perforation 3 abuts the slot 2. The individual zones 6a, 6b, 6c now have different elasticities. This can be ideally achieved, for example, in terms of production, by the material of the membrane 6 having a different material thickness in the area of ​​the individual zones 6a, 6b, 6c. In the illustration of the Figure 8 , a sectional view of a section of the spout 1 along the line CC in Fig. 7 This can be seen in the illustration of the Figures 7 and 8The zones 6a and 6c of the membrane 6 arranged at the top and bottom are correspondingly thicker and thus less elastic than the middle zone 6b of the membrane 6 arranged between them. As a result, sufficient deformation can be achieved in the area of ​​the zones 6a, 6c with medium elasticity to seal different diameters of the cables 5 or elongated objects. The zone 6b of the membrane 6, which has a higher elasticity, then allows sufficient deformation of the membrane 6 to be able to realize a secure and reliable installation and sealing around the entire circumference of the cable 5. The somewhat stiffer zones 6a, 6c in the immediate vicinity of the part of the frame element 4 against which the perforation 3 rests, allow sufficient strain relief.

[0040] In the presentation of the Figure 9 is an alternative to the representation in Figure 7 shown, which in the section according to the line BB in Fig. 2would look exactly like the representation in Fig. 6 The only difference now is that the boundaries between zones 6a, 6b, 6c are no longer straight, but in this example, curved. It is advantageous if the curved boundaries between zones 6a, 6b, 6c are also designed in such a way that the different elasticities of the individual zones 6a, 6b, 6c and of the part of the frame element 4 in the area of ​​the recess 2 are applied over the circumference of the perforation 3. Nevertheless, the area of ​​zone 6b can be enlarged, in particular without changing the division of zones 6a, 6b, 6c around the circumference of the perforation 3. The radial course of the boundaries beginning from the perforation 3 also enables a very clear demarcation of zones 6a, 6b, 6c and their elasticities from the respective sections of the circumference of the perforation 3.

[0041] Another variant again with the cuts according to the line BB and AA according to the Figures 2 and 3 is in the Figures 10 and 11 The difference here is essentially that the recess 8 has been omitted. The perforation 3 thus touches the frame element 4 tangentially in the area of ​​the slot 2, without the latter having the recess 8 described above. The boundaries between the individual zones 6a, 6b, 6c run, as can be seen from the illustration of the Figure 11 can be seen, again in such a way that they intersect within the hole 3 in its extension at the intersection point of the hole 3 with the slot 2. They are designed in a straight line, comparable to the illustration of the Figure 7 However, they could also be designed according to Figure 9 , i.e. with curved boundaries.

[0042] Another variant of the nozzle 1 is shown in the illustrations of the Figures 12 and 13Again, in a sectional view, the section lines AA and BB correspond. In the case shown here, the recess 8 is present again. Unlike in the illustration of the Figures 6, 7 and 9 The recess 8 is not designed with the diameter of the hole, i.e. the approximately smallest diameter of an elongated object or cable 5 to be reliably accommodated, but with a larger diameter. The circular segment-shaped recess 8 thus enables a further improvement of the sealing, in particular with cables 5 or elongated objects with a significantly larger diameter than the diameter of the hole 3. In this case, for a reasonable seal in the design variant of the Figures 6, 7 and 9the material of the frame element 4 is minimally deformed, which requires an elastic frame element 4. Due to the still circular segment-shaped, but with a larger diameter recess in the variant of the Figures 12 and 13 , this is no longer the case. The diameter of the circular segment-shaped recess 8 can be Figures 12 and 13 For example, it can be realized with the largest diameter of the elongated object 5 to be accommodated, so that the latter can use a minimal remainder of the membrane 6 between the tangential contact points of the perforation 3 and the frame element 4 in the area of ​​the slot 2 for smaller diameters to improve the seal and can displace it accordingly for the largest diameter to be accommodated. If the diameter of the circular segment-shaped recess 8 in the variant of the Figures 12 and 13If the diameter is increased even further, a very good seal is still possible even if elongated objects or cables 5 are inserted that exceed the permissible maximum diameter.

[0043] The structure of the membranes 6 has again, as shown in the illustration of the Figure 13 As can be seen, the three zones 6a, 6b, 6c of different elasticity in the structure have a straight boundary. Here, too, a curved boundary would naturally be possible, analogous to the representation in Figure 9 Or a differently shaped border, for example, with a wavy or similar shape, is conceivable in principle. The individual aspects of the design variants can thus be combined with each other according to all the figures described so far.

[0044] In the presentation of the Figure 14The grommet 1 is shown in a generally customary and usual form, which is designed on two of its sides transversely to the longitudinal direction L for receiving, for example, in a frame, a slot in a housing or the like. The upper side is flat here, for example, to be able to be pressed together with another grommet 1. The underside can be flat or, for example, with the same profile as the side edges. The membrane 6 with the perforation 3 is here opposite to the one in Figure 1 schematically shown embodiment variant is set back in the longitudinal direction L relative to an outer surface or outer face 9 of the grommet 1 on its respective side, so that the pressing of the cable 5 between the two membranes 6 takes place in an area in which the grommet 1 is also correspondingly pressed by the material of the housing of the frame or the device receiving it, in order to thus realize an even more reliable seal.

[0045] In the presentation of the Figure 15a section of a grommet 1 with a possible course of the slit 2 in the longitudinal direction L is shown. The slit 2 begins in this case with a straight section in the area of ​​the membrane 6 shown here on the right, which is only shown in dashed lines as being inside the grommet 1, and then runs upwards in a first trapezoidal step, to directly merge into a second trapezoidal step running downwards, in turn ending with a straight section in the area of ​​the other membrane 6. Of course, a straight section between the two trapezoidal steps would also be conceivable, and it would also be conceivable for the trapezoids to connect directly to the outer sides 9 of the grommet 1, so that the straight part is missing entirely or is only present between the two trapezoidal steps. Of course, other types of steps, such as rectangular steps or a larger number of steps, are also conceivable.However, the trapezoid offers the advantage that the parts can easily fit together.

[0046] In principle, only one trapezoidal step upwards is possible in an otherwise straight design of the slot 2 in the longitudinal direction L. This design variant can be combined with all previously described design variants.

[0047] In the presentation of the Figure 16In addition, a section of the slot 2 of the grommet 1 with frame elements 4 shown at a distance is shown. It has, for example, in a straight section, here on the lower surface, a truncated cone-shaped guide element 13, which can dip into a corresponding opening 14 on the part of the frame element 4 forming the opposite side of the slot 2 when the two surfaces of the frame elements 4 come to rest on one another in order to close the slot 2. Such a guide element 13 with a corresponding opening 14 can be combined with different shapes of the slot 2. It is particularly suitable for a section in which the slot 2 runs straight. It can be arranged multiple times distributed over the surface of the slot 2 in order to ensure good positioning of the parts of the frame element 4 against one another when the grommet 1 is pressed together and thus to further improve the sealing of the slot 2.Of course, it can be provided that each of the frame parts 4 has both guide elements 13 and openings 14, wherein the respective guide elements 13 of one part of the frame element 4 dip into the respective corresponding recesses 14 of the respective other part.

[0048] A further fundamental possibility for the design of the slot 2, which can also be combined with the previously described variants, is shown in Figure 17shown. The viewing direction here is along the elongated object to be inserted, i.e. in the longitudinal direction L, to the grommet 1 or the section thereof shown. The slot 2 runs from a point of contact in each cross-sectional area transversely to the longitudinal direction L from the perforation 3 with a step outwards. A plurality of steps or a design in the manner of a tongue and groove, i.e. one step leading upwards and another leading downwards, are also conceivable here. This lateral division of the frame elements 4 in the region of the slot 2 can also serve to improve the positioning of the frame parts 4 relative to one another and thus ultimately to improve the seal.

[0049] The grommets 1 can, as is known from the prior art, be provided and used in different sizes and dimensions, both in terms of the external dimensions and the perforations 3. They can, for example, be used in frames, as is known from the applicant's German patent specification mentioned above. In the illustration of the Figure 15Another possible application is illustrated using an exploded view. The grommet 1 with the slot 2 and the perforation 3 is held between two halves 10, 11 of a cable bushing, which can be clipped around the grommet 1. The cable bushing can then, for example, be inserted into a round hole in a control cabinet or the like and fixed there with a nut on a thread 12, which is created after the two halves are put together and clipped together. This is also known from the prior art and thus represents only one of many conceivable and known possibilities for using such grommets, in this case a grommet 1 with the arrangement of the membranes 6 and the perforation 3 designed according to the invention.

[0050] In addition to the described use with a variety of different frames, such as here with halves 10 and 11, the grommets 1 can of course also be used without such frames in which they are housed. For example, the grommets 1 could have a round cross-section and a groove on the outside, so as to be inserted into a round hole in a sheet metal wall, for example, a control cabinet or the like. Insertion into suitable recesses in a housing, for example, for introducing cables into the housing, is also possible.

Claims

1. Bushing (1) made of a material which is elastic at least in some sections for accommodating at least one elongated object (5) for traction relief and sealing, having an outer frame element (4), which can be folded open along a slot (2), having at least two membranes (6), which are spaced apart in the longitudinal direction of the elongated object (5) to be accommodated and which each have a hole (3) of equal size aligned with one another to accommodate an elongated object (5), characterized in that the respective hole (3) of the at least two membranes (6) touches the material of the frame element (4) on the side of the slot (2), wherein at least one of the membranes (6) has precisely three zones (6a, 6b, 6c) of differing elasticity over the circumference of the holes, and wherein the middle zone (6b), which is arranged between the two other zones (6a, 6c), transversely to the longitudinal direction (L) of the elongated object (5) to be accommodated has a higher elasticity than the two adjacent zones (6a, 6c).

2. Bushing (1) as claimed in claim 1, characterized in that the frame element (4) and the membrane (6) are made of the same material.

3. Bushing (1) as claimed in claim 1 or 2, characterized in that precisely two membranes (6) are provided.

4. Bushing (1) as claimed in claim 1, 2, or 3, characterized in that the frame element (4) has a recess (8) in the area of the touch by the holes (3).

5. Bushing (1) as claimed in any one of claims 1 to 4, characterized in that the hole (3) touches the frame element (4) in the area of each cross section perpendicular to the longitudinal direction (L) of the elongated object (5) to be accommodated at the point in which the end of the slot (2) facing toward the hole (3) is located.

6. Bushing (1) as claimed in claim 4 or 5, characterized in that the recess (8) is designed in the form of a circle segment viewed in cross section.

7. Bushing (1) as claimed in claim 6, characterized in that the circle segment of the recess (8) has a larger diameter than the holes (3).

8. Bushing (1) as claimed in any one of claims 1 to 7, characterized in that the zones (6a, 6b, 6c) of differing elasticity have a different thickness of the membrane (6).

9. Bushing (1) as claimed in any one of claims 1 to 8, characterized in that the zones (6a, 6b, 6c) have straight boundaries in relation to one another originating from the hole (3).

10. Bushing (1) as claimed in claim 9, characterized in that extensions of the boundaries between the zones (6a, 6b, 6c) intersect at the point of the touch of the holes (3) on the frame element (4).

11. Bushing (1) as claimed in any one of claims 1 to 8, characterized in that the zones (6a, 6b, 6c) have curved boundaries originating from the hole (3).

12. Bushing (1) as claimed in any one of claims 1 to 11, characterized in that three zones (6a, 6b, 6c) having two different elasticities are provided, wherein the middle zone (6b), arranged between the two other zones (6a, 6c), transversely to the longitudinal direction (L) of the elongated object (5) to be accommodated has a higher elasticity than the two adjacent zones (6a, 6c).

13. Bushing (1) as claimed in any one of claims 1 to 12, characterized in that the two or the two outer membranes (6) are each arranged offset inward in the longitudinal direction (L) of the elongated object to be accommodated in relation to an outer boundary surface (9) of the bushing (1).

14. Bushing (1) as claimed in any one of claims 1 to 13, characterized in that the slot (2) has at least one, in particular trapezoidal step in the longitudinal direction (L) of the elongated object (5) to be accommodated.

15. Bushing (1) as claimed in any one of claims 1 to 14, characterized in that the parts of the frame element (4) in the area of the slot (2) have at least one guide element (13) on the one part and at least one corresponding opening (14) on the other part.

16. Bushing (1) as claimed in any one of claims 1 to 15, characterized in that the slot (2) has at least one step transversely to the longitudinal direction (L) of the elongated object (5) to be accommodated.