Self-clamping strain relief and EMI protection clamp

Abstract

Self-clamping strain relief and EMI protection clamp (10) for guiding a cable (20) along an object, comprising a first and a second arm (1, 1') for clamping the cable (20), wherein the arms (1, 1') are spaced apart from each other and connected to each other via a base (4).

Description

[0001] The present invention relates to a self-clamping strain relief and EMI protection clamp for guiding a cable along an object, comprising a first and a second arm for clamping the cable, the arms being spaced apart from one another and connected to one another via a base.

[0002] The terminal described here is an electromechanical component that can be used, for example, in connection with electric motor drives or other high-voltage applications.

[0003] Conventional clamps are used to route cables in applications in a mechanically and electrically safe manner. They typically require a certain amount of effort during installation of the clamp and / or cable routing.

[0004] The object of the present invention is to provide an improved clamp that facilitates its assembly and cable routing. This object is achieved by a clamp according to claim 1. Advantageous embodiments of the invention are subject to the dependent claims.

[0005] According to claim 1, a self-clamping strain relief and EMI protection clamp for guiding a cable along an object is provided. The clamp comprises first and second arms for clamping the cable, the arms being spaced apart from one another and connected by a base.

[0006] The present invention makes it possible to reduce the number of components and special fasteners or tools required for the clamp. The clamp provides a strain relief function to reduce stress on the cable while simultaneously providing EMI shielding for the cable. Routing and, in particular, positioning the cable is thus made easier.

[0007] In a preferred embodiment of the invention, one of the arms comprises at least one shielding notch for piercing or puncturing the outer sheath of the cable. The shielding notch may be formed integrally with the corresponding arm. It may be coplanar with an outermost portion of the arm, wherein the outermost portion of the arm may preferably function as an insertion portion to facilitate insertion of the cable into the terminal.

[0008] In another preferred embodiment of the invention, each arm comprises a clamping portion and a spring portion, the spring portion connecting the respective clamping portion to the base. The clamping portions are provided for holding the cable. The spring portions separate the clamping portions from the base so that the cable can be held at a distance from the base. The spring portions can be sized such that the cable is at a distance of approximately the diameter of the cable from the base. The opposing portions of each clamping portion and / or spring portion can be bent away from each other.

[0009] In another preferred embodiment of the invention, a shaped hole is provided between the spring portion and the clamping portion. The shaped hole can facilitate bending of the clamp during its manufacture, so that the spring portion and the clamping portion can be easily bent in a well-defined manner. The shaped hole can extend in a longitudinal direction of the clamp, i.e., in a direction in which the cable is aligned within the clamp.

[0010] In another preferred embodiment of the invention, the arms are shaped such that the cable can be inserted into the arms for clamping the cable to the clamp. In particular, a first arm with two opposite arm portions holds the cable in a first position, and a second arm with two opposite arm portions holds the cable in a second position, the two arms being spaced apart from each other in the longitudinal direction of the clamp. Both arms can comprise upper portions opposite the base that are shaped to facilitate the insertion of the cable and can therefore serve as insertion areas. Each insertion area can comprise two opposite portions that are bent away from each other to facilitate the insertion of the cable.

[0011] In another preferred embodiment of the invention, the base comprises a mounting through-hole, preferably provided between the two arms. The mounting through-hole may be circular and / or positioned so that it is easily accessible for a tool between the two arms.

[0012] In another preferred embodiment of the invention, the base comprises a locking portion for fixing the clamp relative to the object. The locking portion may extend away from the base and in a direction opposite to the arms. The locking portion may be formed integrally with the rest of the base. The locking portion may be positioned in the longitudinal position of one of the arms, wherein the longitudinal position refers to a position in the longitudinal direction of the clamp, i.e., in a direction in which the cable is aligned with the clamp.

[0013] In another preferred embodiment of the invention, the clamp is a stamped component and / or is made from an integral steel part. Multiple bending steps may be performed to form the clamp.

[0014] In another preferred embodiment of the invention, the steel part forming the clamp is H-shaped. The H-shape can be selected so that, when cutting the steel part from a sheet, adjacent H-shaped steel parts can be arranged in an engagement sequence to optimize the use of the sheet material. To achieve this, the dimensions of the H-shaped steel part can be selected so that the distance between the two arms of a first steel part is sufficiently large so that the arms of an adjacent steel part can be inserted between the arms of the first steel part.

[0015] In another preferred embodiment of the invention, the clamp is made of a spring steel part.

[0016] In another preferred embodiment of the invention, the base is fixed to the object via a screw mounted in the mounting through hole and the object.

[0017] In another preferred embodiment of the invention, the terminal may be electrically connected to a cable shield and / or the object forming an EMI / EMC shield, such as ground or earth.

[0018] Further details and advantages of the invention are described with reference to the embodiments shown in the figures. In the figures: Fig. 1: a perspective view of a terminal with cable; Fig. 2: a perspective view of the clamp only; Fig. 3: a perspective view of the underside of the clamp; and Fig. 4: another perspective view of the clamp.

[0019] Fig. Figure 1 shows a perspective view of the clamp 10 of the present invention, with a portion of a cable 20 shown positioned within the clamp. The clamp 10 is a self-clamping strain relief and EMI protection clamp that guides the cable 20 along an object. The object itself is not shown in the figure for clarity. The object would be connected to the lower portion of the clamp 10 and opposite the cable 20.

[0020] The clamp 10 comprises a first and a second arm 1, 1' for clamping the cable 20. Each of the two arms 1, 1' can be understood as comprising two opposing halves that interact with each other to hold the cable. The arms 1, 1' are spaced apart from each other and connected to each other via a base 4.

[0021] The clamp 10 makes it possible to reduce the number of components and special fasteners or tools for the clamp 10. To reduce the stress on the cable, the first arm 1 comprises at least one shielding notch 8 for piercing or puncturing the outer sheath 20a of the cable 20. The shielding notch 8 can be formed integrally with the corresponding arm 1. It can be coplanar with an outermost portion of the arm 1. The outermost portion of at least one of the arms 1, 1' can function as an insertion portion 9, 9' to facilitate the insertion of the cable 20 into the clamp 10. It is also within the scope of the invention to provide a clamp 10 with two or more shielding notches 8, wherein each arm 1, 1' can comprise one or two shielding notches 8.

[0022] The terminal 10 can be electrically connected to the cable shield 20b and / or the object forming an EMI / EMC shield, such as ground or earth. The terminal 10 provides an EMI shielding function via its second arm 1', which contacts an internal conductive braid or the cable shield 20b of the cable 20. The cable shield 20b may need to be exposed before inserting the cable 20 into the terminal 10.

[0023] The arrangement of the two arms 1, 1' facilitates the guiding and, in particular, the safe positioning of the cable.

[0024] Each arm 1, 1' may comprise a clamping portion 2, 2' and a spring portion 3, 3', wherein the spring portions 3, 3' connect the respective clamping portions 2, 2' to the base 4. The clamping portions 2, 2' are provided for holding the cable 20, wherein the spring portions 3, 3' provide a closing return of the clamp 10, the portions 2, 2' for holding the cable 20, once the cable 20 has been inserted into the clamp 10.

[0025] The spring portions 3, 3' connect the clamping portions 2, 2' to the base 4 and space them from the base 4 so that the cable 20 can be held at a distance from the base 4. The spring portions 3, 3' can be sized such that the cable 20 is at a distance of approximately the diameter of the cable 20 or more from the base 4. Opposing portions of each of the clamping portions 2, 2' and / or the spring portions 3, 3' can be bent away from each other, meaning that the volume boundary between the opposing portions is increased.

[0026] One or more shaped holes 7, 7' may be provided between the spring regions 3, 3' and the clamping regions 2, 2' of some or all of the arms 1, 1. The shaped hole 7, 7' may facilitate bending of the clamp, so that the spring region 3, 3' and the clamping region 2, 2' can be easily bent in a well-defined manner. The shaped hole 7, 7' may extend in a longitudinal direction of the clamp, i.e., in a direction in which the cable 20 is aligned within the clamp. The shaped hole 7, 7' may extend over approximately half the width of the respective arm 1, 1'. The shaped hole 7, 7' may be positioned on a portion of the arms 1, 1' that is bent inwards. An arm 1, 1' may comprise two opposite shaped holes 7, 7', one at each connecting portion provided between a spring portion 3, 3' and its adjacent clamping portion 2, 2'.

[0027] The arms 1, 1' can be shaped such that the cable 20 can be inserted into the arms 1, 1' for clamping the cable 20 to the clamp 10. In particular, a first arm 1 with two opposite arm sections holds the cable 20 in a first position, and a second arm 1' with two opposite arm sections holds the cable in a second position. The two arms 1, 1' can be arranged in the longitudinal direction of the clamp 10, which corresponds approximately to the horizontal direction in Fig. 1 and the direction in which the base 4 extends. Both arms 1, 1' may comprise upper end portions opposite the base 4, which are shaped to facilitate the insertion of the cable 20, and are the insertion areas 9, 9'. Each insertion area 9, 9' may comprise two opposite portions that are bent away from each other to facilitate the insertion of the cable 20. In the view of Fig. 1 the cable can be inserted into terminal 10 in the direction from top to bottom.

[0028] The clamp 10 may be provided such that the arms 1, 1' with the notch 8 are at least partially bendable in an outward direction to remove the cable 20 from the clamp 10. This ensures that the notch 8 disengages from the cable outer sheath 20a, thereby preventing it from causing further damage beyond an initial penetration.

[0029] Fig. Figure 2 shows a perspective view of the electrical terminal 10. For clarity, the figure does not show the cable 20. The terminal 10 is shown in its unused or empty state. The spring portions 3, 3' of each arm 1, 1' force the arms 1, 1' into a shape in which the gap defined by each of the arms 1, 1' and used to hold the cable 20 is narrower than in Fig. 1 is.

[0030] Fig. Figure 3 is a perspective view of the underside of the clamp 10. The base 4 is shown extending along the hole length of the clamp 10. The base can be understood as being at least partially part of the arms 1, 1' and at the same time connecting the arms 1, 1' to each other.

[0031] The base 4 may include a mounting through hole 6, which may be provided between the two arms 1, 1'. The mounting through hole 6 may be circular and / or positioned so that it is easily accessible for a tool between the two arms 1, 1'.

[0032] The base 4 of the clamp 10 can be attached to the object via a screw mounted both in the mounting through hole 6 and in the object. The screw and the object are not shown in the figures to better illustrate the geometry of the clamp 10.

[0033] The base 4 is also shown as including a locking portion 5 for fixing the clamp 10 relative to the object. Specifically, when a screw fixes the clamp 10 to the object via the mounting through-hole 6, the locking portion 5 can be at least partially inserted directly or indirectly into the object, preventing the clamp 10 from rotating about the screw.

[0034] The locking portion 5 may extend away from the base 4 and in a direction opposite to the arms 1, 1'. The locking portion 5 may be formed integrally with the rest of the base 4. The locking portion 5 may be positioned in the longitudinal position of one of the arms 1, 1'. The locking portion may be a flat portion, which may preferably be angled at an angle of 90° ± 10° to the base.

[0035] The clamp 10 may be manufactured as a stamped component and / or may be made from an integral steel part. Multiple bending steps may be performed to form the clamp 10, and in particular its arms 1, 1' and its locking portion 5.

[0036] The steel part forming the clamp 10 can be H-shaped. The H-shape can be selected so that, when cutting the steel part from a sheet, the H-shaped steel parts can be arranged in an engagement sequence to optimize the use of the sheet material. To achieve this, the dimensions of the H-shaped steel part can be selected such that the distance between the two arms 1, 1' of a first steel part is sufficiently large so that the arms 1, 1' of an adjacent steel part can be inserted between the arms 1, 1' of the first steel part.

[0037] In the embodiment of Fig. 3, the width of the arms 1, 1' may correspond approximately to one-third of the length of the clamp, i.e., its extension in the direction in which the arms 1, 1' are positioned next to each other. The gap between the arms 1, 1' may also correspond approximately to the width of the arms 1, 1'. This geometry of the clamp 10 minimizes the amount of material required to provide the clamp 10.

[0038] The clamp 10 may be made from a spring steel member or an alternative material capable of providing the elastic restoring force to hold the cable 20 in position while being sufficiently robust to withstand the stresses to which it is subjected during use.

[0039] Fig. 4 is another perspective view of the clamp. As in Fig. 2 and Fig. 3 shows the terminal without the cable 20. Reference numbers 1, 1' First and second arm 2.2' clamping range 3, 3' spring range 4 Base 5 Locking section 6 mounting through hole 7, 7' forming hole 8 Shielding notch 9, 9' introduction area 10 terminal 20 cables 20a cable outer sheath 20b cable shielding 20c cable wire

Claims

[1] Self-clamping strain relief and EMI protection clamp (10) for guiding a cable (20) along an object, comprising a first and a second arm (1, 1') for clamping the cable (20), the arms (1, 1') being spaced apart from one another and connected to one another via a base (4). [2] Terminal (10) according to claim 1, characterized by that one of the arms (1, 1') comprises at least one shielding notch (8) for piercing or puncturing the outer sheath (20a) of the cable (20). [3] Terminal (10) according to one of the preceding claims, characterized by that each arm (1, 1') comprises a clamping area (2, 2') and a spring area (3, 3'), wherein the spring area (3, 3') connects the respective clamping area (2, 2') to the base (4). [4] Terminal (10) according to claim 3, characterized by that a shaped hole (7) is provided between the spring area (3, 3') and the clamping area (2, 2'). [5] Terminal (10) according to one of the preceding claims, characterized by that the arms (1, 1') are shaped such that the cable (20) can be inserted into the arms (1, 1') for clamping the cable (20) to the terminal (10). [6] Terminal (10) according to one of the preceding claims, characterized by that the base (4) comprises a mounting through-hole (6), which is preferably provided between the two arms (1, 1'). [7] Terminal (10) according to one of the preceding claims, characterized by that the base (4) comprises a locking portion (5) for fixing the clamp (10) relative to the object. [8] Terminal (10) according to one of the preceding claims, characterized by that the clamp (10) is a stamped component and / or is made from an integral steel part. [9] Terminal (10) according to claim 8, characterized by that the steel part forming the clamp (10) is H-shaped. [10] Terminal (10) according to one of the preceding claims, characterized by that the clamp (10) is made of a spring steel part. [11] Terminal (10) according to at least claim 6, characterized by that the base (4) is fixed to the object via a screw mounted in the mounting through hole (6) and the object. [12] Terminal (10) according to claim 11, characterized by that the terminal (10) can be electrically connected to a cable shield (20b) and / or the object forming an EMI / EMC shield, such as ground or earth.

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