Strain-relief means at a cable outlet, and plug-in connector

Abstract

The present invention relates to a strain-relief means (100) at a cable outlet (102), for example of a plug-in connector, wherein a closure body (108) with a cable passage (110) is arranged in the cable outlet (102) and a cable (106) is arranged in the cable passage (110), wherein an external dimension (112) of the closure body (108) is greater than an internal dimension (114) of the cable outlet (102) when the closure body (108) is in a relaxed state, wherein the closure body (108) arranged in the cable outlet (102) is crimped and the external dimension (112) corresponds to the internal dimension (114) in the crimped state, wherein the cable passage (110) at least clamps on a sheath (116) of the cable (106) and acts as a strain-relief means (100) in the crimped state.

Description

[0001] Strain relief on a cable outlet and connector

[0002] Technical area

[0003] The present invention relates to a strain relief at a cable outlet, as well as a connector with such a strain relief.

[0004] State of the art

[0005] The present invention will be described below mainly in connection with strain reliefs for electrical cables.

[0006] Forces, especially tensile forces, can act on a cable. To keep these forces away from the connection points of the cable's electrical conductors, strain relief can be used to divert the forces to a housing surrounding the electrical connection points, for example, a connector.

[0007] Strain relief can be achieved, for example, with a clamp that clamps the cable jacket against the housing. The clamp can be screwed to the housing or fixed to the housing.

[0008] Alternatively, strain relief can be provided via clamping plates on a cable gland in the housing. The cable is pushed through the clamping plates after a union nut of the cable gland has been pushed onto the sheath. When the union nut is screwed onto the cable gland, the clamping plates are pressed against the cable, thereby gripping the sheath.

[0009] If the clamping blades are mounted on a loose clamping ring, which is also pushed onto the cable before the union nut is tightened, an elastic seal can be placed between the clamping ring and the cable gland and squeezed together when screwed on. The seal can create a fluid-tight seal for the cable gland.

[0010] Description of the invention

[0011] One object of the invention is therefore to provide improved strain relief at a cable outlet, as well as an improved connector, using the simplest possible design. Such improvements may, for example, relate to simplified manufacturing and a reduced number of parts.

[0012] This object is achieved by the subject matter of the independent claims. Advantageous developments of the invention are specified in the dependent claims, the description, and the accompanying figures.

[0013] In the approach presented here, a closure body for a housing opening is pushed onto a cable that passes through the opening. The closure body, along with the cable, is then inserted into the opening. The closure body has an oversize relative to the opening. During insertion, the closure body is squeezed and clamped onto the cable.

[0014] The approach presented here reduces the number of parts required for a strain relief. The strain relief is achieved through a single component and a suitable opening. This allows the strain relief to be manufactured easily and cost-effectively.

[0015] According to a first aspect, a strain relief is proposed on a cable outlet, wherein a closure body with a cable passage is arranged in the cable outlet and at least one cable is arranged in the cable passage, wherein an outer dimension of the closure body in a relaxed state of the closure body is greater than an inner dimension of the cable outlet, wherein the closure body arranged in the cable outlet is squeezed and the outer dimension in the squeezed state corresponds to the inner dimension, wherein the cable passage in the squeezed state at least clamps on a sheath of the cable and acts as a strain relief.

[0016] According to a second aspect, a connector is proposed which has a housing with a cable outlet, wherein a strain relief according to the first aspect is arranged in the cable outlet.

[0017] At a cable outlet, at least one cable can be routed through a wall of a housing into the housing. The housing can be, for example, a housing for a connector or plug. The cable outlet can be an opening in the housing. The cable outlet can be cylindrical. The cable outlet can be designed as a tube stub and protrude from the housing. The cable outlet can have a round cross-section. The cable outlet can also be a simple recess or a hole in the housing. The closure body can be inserted, pushed, glued, or welded into the cable outlet.

[0018] A closure body can be referred to as a plug or end cap. A cable outlet can consist of at least one recess through the closure body. The cable outlet can be cylindrical. The cable outlet can be designed as a bore or hole in the closure body. The cable outlet can have a round cross-section. The cable outlet can be arranged centrally in the closure body. The closure body can, for example, be substantially rotationally symmetrical.

[0019] An external dimension can be referred to as an outer dimension or outer diameter. The outer dimension can be measured transversely to a cable extension direction. The closure body can have a round cross-section. In this case, the external dimension can be referred to as an outer diameter. Alternatively, the closure body can be square. The closure body can have rounded corners. A square end cap can have a length and a width transverse to the cable extension direction, as well as a thickness in the cable extension direction.

[0020] An inner dimension can be referred to as an inner dimension or an inner diameter. The inner dimension can be measured perpendicular to the cable's extension direction. If the cable gland is clamped to the jacket, strain relief can be provided via a friction fit and / or a form fit.

[0021] The closure body can have at least one slot between the cable outlet and an outer side of the closure body. The slot can be closed when crimped. The slot can be a cut and introduced after manufacturing. The slot can be a recess and formed by an injection molding tool. The slot allows the closure body to be deformed more easily. The slot allows the closure body to be placed laterally onto the cable. The closure body can be bent open or closed at the slot. The flanks of the slot can lie close together when crimped.

[0022] The slot can have at least one transverse offset. A transverse offset can be a change in the slot's direction. The transverse offset can cause the flanks to overlap. Due to the transverse offset, the slot, when squeezed, can be fluid-tight against water jets, such as a jet from a high-pressure cleaner.

[0023] The closure body can have an additional slot. The additional slot can extend almost to the outside. A bend can be arranged in the area of ​​the outside. The additional slot can be arranged as an extension of the slot on an opposite side of the cable outlet. Both slots can divide the closure cap into essentially equal parts. The parts are connected to each other at the bend. The bend can be referred to as a foil hinge. The bend can have a significantly lower bending resistance than the rest of the closure body. The bend can be bent open to widen the closure body. The bend can be bent together when the closure body is crimped. The bend allows the closure body to be easily placed sideways on the cable.

[0024] When the sealing body is in its relaxed state, the inner dimension of the cable opening can be larger than the outer dimension of the sheath. This allows the sealing body to be easily pushed onto the cable and slid along the cable.

[0025] Alternatively, the inner dimension of the cable opening in the relaxed state of the closure body can be smaller than the outer dimension of the cable sheath. In this case, the cable opening can be widened to accommodate the cable and allow it to be moved along the cable. The closure body can clamp onto the cable in the unexpanded state. In particular, the closure body can be slotted, and the slot can be spread open to widen the cable opening.

[0026] The inner dimension of the cable outlet can be smaller when crimped than the outer dimension of the sheath when relaxed. The sealing body can compress the sheath when crimped. The sheath can be elastic or have elastic components. The sheath can be compressed. Compression can create a frictional and positive connection between the sealing body and the cable.

[0027] At least one rib for clamping the sheath can be arranged in the cable outlet. The rib can protrude radially inwards. The inner dimension of the cable outlet can, at least in the area of ​​the rib in the crimped state, be smaller than the outer dimension of the sheath in the relaxed state. The rib can crimp the sheath when crimped. A rib can be a raised area surrounding the cable outlet. The at least one rib can have different profiles. For example, the rib can be angular, for example triangular or trapezoidal. The rib can also be rounded, for example semicircular or circular segment-shaped. The rib penetrating the sheath can create a positive connection between the closure body and the cable.

[0028] The closure body can have a conical surface on an outer side with a smaller outer dimension. The closure body can be squeezed if the conical surface slips over an inner side of the cable outlet when the closure body is arranged in the cable outlet. The smaller outer dimension can be smaller than the inner dimension of the cable outlet. The closure body can taper from the outer dimension. On a conical surface, a wedge effect can generate a squeezing force when arranged or pressed into the cable outlet. The squeezing force can be greater than the force required for arrangement. The conical surface can be a section of the outer side. Several conical surfaces can give the outer side a stepped shape. Cylindrical sections can be arranged between the conical surfaces. Alternatively, almost the entire outer surface can be conical. The cable outlet can have a conical surface on an inner side with a larger inner dimension.The locking body can be crushed if the outer surface of the locking body slips over the conical surface when it is positioned in the cable outlet. The larger inner dimension can be larger than the outer dimension of the locking body. The cable outlet can widen from the inner dimension. The conical surface can act as a funnel or insertion chamfer. The wedge effect can also generate a crushing force on this conical surface.

[0029] The conical surfaces can be present on both the closure body and the cable outlet. The conical surfaces can slide against each other, thus avoiding high point loads.

[0030] Alternatively, both the closure body and the cable outlet can be designed without conical surfaces. In this case, the closure body can be crimped together outside the cable outlet using a suitable tool and, in the crimped state, inserted into the cable outlet. The closure body can also be crimped more tightly than the internal dimensions of the cable outlet. The closure body can then be inserted into the cable outlet with a low setting force. In the cable outlet, the closure body can relax slightly and fill the cable outlet.

[0031] The closure body can have at least one locking device for locking onto the housing. The locking device can lock onto a counterpart of the housing when the closure body is arranged in the cable outlet. A locking device can comprise at least one tab or at least one hook. The tab can slide on the hook and be elastically deformed in the process. Behind the hook, the tab can spring back and create a positive connection between the hook and the tab. The locking device can be arranged on an outer side of the cable outlet. The locking device can encompass an edge of the cable outlet.

[0032] The closure body can be made of a hard plastic, at least in part. The closure body can also be made of a soft component in part. The closure body can also be made entirely of the hard plastic. A material forming the closure body can be harder than a material of the sheath of the cable to be accommodated therein. The closure body can be formed in one piece. The closure body made of hard plastic can, in particular, be slotted. The hard plastic can have good sliding properties. This allows the closure body to be easily inserted into the cable outlet. Conical surfaces of the closure body and / or the cable outlet can also slide slightly and squeeze the closure body or slightly widen the cable outlet.

[0033] Short character description

[0034] Advantageous embodiments of the invention are explained below with reference to the accompanying figures. They show:

[0035] Fig. 1 shows a representation of a strain relief according to an embodiment;

[0036] Fig. 2 shows a representation of a non-installed strain relief according to an embodiment;

[0037] Figs. 3 and 4 show sectional views through installed and uninstalled strain reliefs according to exemplary embodiments; and Fig. 5 shows a slot with lateral offset on a strain relief according to an exemplary embodiment.

[0038] The figures are schematic representations and serve only to illustrate the invention. Identical or equivalent elements are provided with the same reference numerals throughout.

[0039] Detailed description

[0040] Fig. 1 shows a representation of a strain relief 100 according to an exemplary embodiment. The strain relief 100 is provided at a cable outlet 102 of a housing 104. A cable 106 extends through the cable outlet 102 out of the housing 104. The cable 106 can be referred to as a sheathed cable. The strain relief 100 is formed in a closure body 108 of the cable outlet 102. The closure body 108 is arranged in the cable outlet 102 and closes the cable outlet 102. The closure body 108 has at least one cable passage 110 for the cable 106. The cable 106 thus runs through the cable passage 110.

[0041] In a relaxed state, the closure body 108 has an outer dimension 112 that is larger than an inner dimension 114 of the cable outlet 102. Since the closure body 108 is arranged in the cable outlet 102, the closure body 108 is compressed radially to such an extent that its outer dimension 112 essentially corresponds to the inner dimension 114 of the cable outlet 102. As a result, the cable passage 110 is narrowed to such an extent that it at least clamps onto a sheath 116 of the cable 106 and acts as a strain relief 100.

[0042] Here, the cable outlet 102 is a hollow cylinder that protrudes from the housing 104. The hollow cylinder has a circular cross-section. The closure body 108 is arranged essentially entirely within the hollow cylinder.

[0043] In one embodiment, the closure body is slotted. A slot 118 extends from the cable passage 110 to an outer side of the closure body 108. The slot 118 allows the cable passage 110 to be widened, allowing the closure body to be positioned on the cable 106.

[0044] In one embodiment, the closure body 108 has at least one locking element 120. The locking element 120 engages a counterpart on the cable outlet 102 or housing 104 when the closure body 108 is arranged in a proper end position in the cable outlet 102 and the cable is clamped. The locking element 120 prevents the closure body 108 from falling out of the cable outlet 102, even due to vibrations.

[0045] Here, the locking element 120 is arranged outside the hollow cylinder of the cable outlet 102. The locking element 120 is a locking tab that is engaged with a locking hook on the outside of the hollow cylinder. The locking tab thus engages an edge of the cable outlet 102.

[0046] In one embodiment, an inner dimension of the cable passage 110 is already smaller than an outer dimension of the sheath 116 in the relaxed state. This makes it necessary to bend the closure body 108 at the slot 118 in order to move the cable 106 in the cable passage 110.

[0047] Fig. 2 shows a representation of a non-installed strain relief 100 according to one exemplary embodiment. The strain relief 100 essentially corresponds to the strain relief in Fig. 1. Here, the strain relief 100 is shown in the relaxed state. The cable 106 is already arranged in the cable passage 110, and the closure body 108 is arranged outside the cable outlet 102. In one exemplary embodiment, the inner dimension of the cable passage 110 in the relaxed state is larger than the outer dimension of the sheath 116. This allows the closure body 100 to be easily displaced axially along the cable 116.

[0048] In one embodiment, the slot 118 is open in the relaxed state. The side surfaces of the slot 118 do not touch each other. When the closure body 108 is squeezed together and placed in the cable outlet 102, the slot 118 closes and the side surfaces lie tightly against each other.

[0049] In one embodiment, the closure body 108 has a circumferential flange 200. The closure body 108 is inserted into the cable outlet 102 until the flange 200 rests against the edge of the cable outlet 102. The closure body 108 then reaches its intended end position and acts as the strain relief 100.

[0050] 3 and 4 show sectional views through installed and uninstalled strain relief devices 100 according to exemplary embodiments. The strain relief device in Fig. 3 essentially corresponds to the strain relief device in Figs. 1 and 2. Here, the closure body 108 has a conical surface 300 on its outer side. At the conical surface 300, the closure body 108 tapers to a smaller outer dimension. In the relaxed state of the closure body 108, the smaller outer dimension is smaller than the inner dimension 114 of the cable outlet 102. When the closure body 108 is pressed into the cable outlet 102, the edge of the cable outlet 102 slides over the conical surface 300. The closure body 108 is squeezed together perpendicular to the cable 106, and the outer dimension 112 is essentially reduced to the inner dimension 114. By squeezing together, the cable passage 110 is also reduced in size and clamps as the strain relief 100 on the sheath 116.In one embodiment, the closure body 108 has cylindrical surfaces on the outside before and after the conical surface 300. One cylindrical surface has the outer dimension 112, the other cylindrical surface has the smaller outer dimension. When inserted into the cable outlet 102, the closure body 108 is guided over the cylindrical surface with the smaller outer dimension until the conical surface 300 touches the edge and is squeezed together. When the closure body 108 is squeezed together, the edge slides onto the other cylindrical surface and rests against the cylindrical surface. Due to the cylindrical surface, no ejection force is generated despite the tension of the squeezed closure body 108.

[0051] In one embodiment, a rib 302 is arranged in the cable passage 110. The rib 302 reduces the internal dimensions of the cable passage 110. In the compressed state, the rib 302 penetrates the jacket 116, thereby compressing the jacket 116. This creates a positive connection to the cable 106 in addition to clamping it to the jacket 116.

[0052] Here, the rib 302 has a circular segment-shaped cross-section, i.e. it is strongly rounded and has no sharp edges.

[0053] In one embodiment, the closure body 108 has two diametrically opposed locking elements 120.

[0054] The strain relief 100 shown in Fig. 4 differs from the strain relief shown in Fig. 3 in that the conical surface 300 extends essentially over the entire outer surface. In addition, the rib 302 has sharp edges and a triangular cross-section.

[0055] In one embodiment, the cable outlet 102 has a conical surface 300. The conical surface 300 expands the cable outlet 102 from the inner dimension 114, which is smaller than the outer dimension 112 of the closure body 108 in the relaxed state. Here, too, the outer side of the closure body 108 slides over the conical surface 300 when the closure body 108 is pressed into the cable outlet 102. The closure body 108 is thereby squeezed until the cable passage 110 clamps onto the jacket 116, or until the rib 302 squeezes the jacket 116 and creates a positive connection with the cable 106.

[0056] In one embodiment, both the cable outlet 102 and the closure body 108 have conical surfaces 300. The outer dimension 112 of the closure body 108 is larger than the inner dimension 114 of the cable outlet 102, even when compressed. The conical surfaces 300 abut one another in the end position of the closure body 108. This creates ejection forces on the conical surfaces 300, which are supported by the positive engagement of the locking elements 120.

[0057] In one embodiment, the inner dimension 114 of the cable outlet 102 is widened by pressing in the closure body 108, while the closure body 108 is squeezed together.

[0058] Fig. 5 shows a slot 118 with a lateral offset 500 on a strain relief 100 according to one exemplary embodiment. The strain relief 100 essentially corresponds to the strain reliefs in Figs. 1 to 3. The slot 118 has a step. Due to the lateral offset 500 or the step, the slot 118 does not run in a straight line in the direction of the cable. Due to the lateral offset 500, for example, water jets cannot penetrate the housing through the slot 118.

[0059] In the following, possible embodiments of the invention are summarized again or presented with slightly different wording.

[0060] A one-piece cable strain relief in a connector is presented. In a connector with at least one current path, a certain amount of cable tension is exerted on the connector's interior during assembly in the vehicle and also during operation. This can, for example, negatively impact the technical performance of the connector system due to vibration. In addition, "sheath migration" can occur, in which the cable insulation moves relative to the metal strands when installed. This can, for example, lead to insufficient clearance and creepage distances and to a violation of HV safety. To reduce these potential problems, a strain relief in the connector can fix the cable or cable sheath to the connector housing.

[0061] The connector housing has an area through which the cable passes. In the approach presented here, the cable is clamped to the housing by an additional component. The clamping is similar to a garden hose clamp. A conical contour exerts a clamping force from the housing onto the cable via the individual part(s). The cable clamp is slotted to allow for variations in the outer and inner diameters.

[0062] Traditionally, at least two additional components are required to create a clamping force between the housing and the cable. Alternatively, strain relief can be implemented via the crimp, but this only works with shielded connector systems.

[0063] The approach presented here can be used for all connector systems that require cable strain relief.

[0064] In the approach presented here, the strain relief is integrated directly into the required end cap. This approach results in a reduction in the number of parts required to implement strain relief in the connector system. No additional component is required besides the end cap. If necessary, the connector length can also be reduced.

[0065] During the assembly process, at least one cable is inserted or threaded into the end cap. The end cap can be slotted to further reduce the diameter adjacent to the cable, creating a clamping effect when inserted into the housing. Before joining, there is an air gap between the cable and the end cap to allow for assembly and relative forward and backward movement. The outer diameter of the end cap before joining, which subsequently rests in the connector housing, is larger than in the final assembled state.

[0066] A conical contour on the housing and / or the end cap or cable clamp is used to reduce the outer diameter of the end cap or cable clamp during assembly. This reduction results in the inner contour or inner diameter also shrinking toward the cable, thus clamping or overlapping the cable. This secures the cable or cable sheath. The cable sheath usually has a deformable portion.

[0067] Alternatively, a conical contour can be omitted. In this case, the outer diameter taper is created using an assembly aid or tool, and the end cap is inserted into the housing in a compressed state.

[0068] With the approach presented here, various contours between the housing and the end cap or cable clamp are conceivable. Likewise, various contours between the end cap or cable clamp and the cable are possible, such as flat, pointed, trapezoidal, or bulged. The slot can also be designed in a stepped manner, thus creating an additional interference contour against a high-pressure cleaner water jet. Since the devices and methods described in detail above are exemplary embodiments, they can be modified extensively by those skilled in the art in the usual way without departing from the scope of the invention. In particular, the mechanical arrangements and the relative sizes of the individual elements are merely exemplary.

[0069] LIST OF REFERENCE SYMBOLS

[0070] 100 strain relief

[0071] 102 Cable outlet

[0072] 104 housings

[0073] 106 cables

[0074] 108 breech bodies

[0075] 110 cable outlet

[0076] 112 external dimensions

[0077] 114 internal dimensions

[0078] 116 Coat

[0079] 118 slot

[0080] 120 locking element

[0081] 200 flange

[0082] 300 conical surface

[0083] 302 Rib

[0084] 500 page offset

Claims

CLAIMS 1. Strain relief (100) on a cable outlet (102), wherein a closure body (108) with a cable passage (110) is arranged in the cable outlet (102) and a cable (106) is arranged in the cable passage (110), wherein an outer dimension (112) of the closure body (108) in a relaxed state of the closure body (108) is greater than an inner dimension (114) of the cable outlet (102), wherein the closure body (108) arranged in the cable outlet (102) is crimped and the outer dimension (112) in the crimped state corresponds to the inner dimension (114), wherein the cable passage (110) in the crimped state at least clamps on a sheath (116) of the cable (106) and acts as a strain relief (100).

2. Strain relief (100) according to claim 1, wherein the closure body (108) has at least one slot (118) between the cable passage (110) and an outer side of the closure body (108), wherein the slot (118) is reduced in size in the squeezed state compared to the relaxed state.

3. Strain relief (100) according to claim 2, wherein the slot (118) has at least one lateral offset (500).

4. Strain relief (100) according to one of claims 2 to 3, wherein the closure body (108) has a further slot (118), wherein the further slot (118) extends to just before the outer side, wherein a bending point is arranged in the region of the outer side.

5. Strain relief (100) according to one of the preceding claims, wherein an inner dimension (114) of the cable passage (110) in the relaxed state of the closure body (108) is larger than an outer dimension (112) of the sheath (116).

6. Strain relief (100) according to one of claims 2 to 4, wherein an inner dimension (114) of the cable passage (110) in the relaxed state of the closure body (108) is smaller than an outer dimension (112) of the sheath (116), wherein the cable passage (110) is expandable for arranging the cable (106).

7. Strain relief (100) according to one of the preceding claims, wherein an inner dimension (114) of the cable passage (110) in the crimped state is smaller than an outer dimension (112) of the sheath (116) in a relaxed state, wherein the closure body (108) crimps the sheath (106) in the crimped state.

8. Strain relief (100) according to one of the preceding claims, in which at least one rib (302) for clamping the sheath (116) is arranged in the cable passage (110), wherein an inner dimension (114) of the cable passage (110) at least in the region of the rib (302) in the squeezed state is smaller than an outer dimension (112) of the sheath (116) in a relaxed state, wherein the rib (302) squeezes the sheath (116) in the squeezed state.

9. Strain relief (100) according to one of the preceding claims, in which the closure body (108) has on an outer side a conical surface (300) to a smaller outer dimension (112), wherein the closure body (108) is squeezed when the conical surface (300) slips over an inner side of the cable outlet (102) when the closure body (108) is arranged in the cable outlet (102).

10. Strain relief (100) according to one of the preceding claims, in which the cable outlet (102) has on an inner side a conical surface (300) to a larger inner dimension (114), wherein the closure body (108) is squeezed when an outer side of the closure body (108) slips over the conical surface (300) when the closure body (108) is arranged in the cable outlet (102).

11. Strain relief (100) according to one of the preceding claims, wherein the closure body (108) has at least one latching device (120) for latching onto the housing (104), wherein the latching device (120) latches onto a counterpart of the housing (104) when the closure body (108) is arranged in the cable outlet (102).

12. Strain relief (100) according to one of the preceding claims, wherein the closure body (108) consists at least in regions of a hard plastic.

13. Connector, wherein the connector has a housing (104) with a cable outlet (102), wherein a strain relief (100) according to one of claims 1 to 12 is arranged in the cable outlet (102).

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