The invention relates to a contact sleeve in the form of a hollow cylinder having a casing surface and a center longitudinal axis for an electrical connector for establishing electrical contact with a mating connector, wherein the contact sleeve has at least two pairs of contact spring lamellae on its casing surface, wherein each pair of contact spring lamellae are arranged radially opposite one another on the contact sleeve, wherein each contact spring lamella has a radial raised portion which forms an electrical contact area, wherein the raised portions of a pair of contact spring lamellae which are situated opposite one another are arranged at the same location in the axial direction with respect to the contact sleeve in such a way that the contact areas of said contact spring lamellae lie on a straight line which perpendicularly intersects the center longitudinal axis of the contact sleeve, as claimed in the preamble of patent claim 1.
Connectors, in particular coaxial connectors, serve to releasably connect coaxial cables. Coaxial connectors are of coaxial design like coaxial cables, and they therefore have the advantages of coaxial cables, specifically low electromagnetic influencing and irradiation and also good electrical shielding and also an impedance which corresponds to that of the connected coaxial cable in order to avoid reflection phenomena at the transition point between the coaxial connector and the coaxial cable. In this case, a coaxial cable, also called coax cable for short, is understood to mean a 2-pole cable of concentric design which has an internal conductor (also called core) which is surrounded by a hollow-cylindrical external conductor at a constant distance. The external conductor shields the internal conductor against electromagnetic interference radiation. An insulator or dielectric is arranged in the intermediate space between the internal conductor and the external conductor.
Coaxial connectors are designed to provide a predetermined characteristic impedance, for example of 50 Ω, in order to ensure reflection-free transmission of RF signals. The characteristic impedance of a coaxial connector depends, amongst other things, on the ratio of the inside diameter of the external conductor and the diameter of the internal conductor. Therefore, electrical connection of a coaxial cable to a coaxial connector requires coaxial connectors which are matched to the respective inside diameter and outside diameter of the coaxial cable.
The invention is based on the object of improving a contact sleeve in respect of manual handling during connection to a mating connector.
According to the invention, this object is achieved by a contact sleeve of the abovementioned type having the features identified in claim 1. Advantageous refinements of the invention are described in the further claims.
To this end, the invention provides, in the case of a contact sleeve of the abovementioned kind, that the raised portions of at least one first pair of contact spring lamellae are arranged in a manner offset by a predetermined axial offset length in the axial direction with respect to the contact sleeve relative to the raised portions of at least one second pair of contact spring lamellae.
This has the advantage that, when the contact sleeve is inserted into a mating plug in the axial direction, the raised portions make mechanical and electrical contact with the mating plug only one after the other, so that plugging forces are reduced.
For the purpose of making corresponding electrical and mechanical contact with the mating plug radially on the inside or outside with respect to the contact sleeve, the raised portions rise radially inward and/or outward beyond the contact sleeve or beyond the casing wall.
A particularly good reduction in the plugging forces when there are a large number of electrical contact areas at the same time is achieved in that three pairs of contact spring lamellae with respective raised portions are formed on the contact sleeve, wherein the raised portions of each pair is arranged in an offset manner in the axial direction relative to the raised portions of all of the other pairs.
A contact sleeve which is particularly simple to produce is achieved in that the contact spring lamellae are formed by recesses in the contact sleeve or the casing wall of the contact sleeve which are arranged at a distance from one another in the circumferential direction.
Contact spring lamellae which are particularly stable and mechanically resistant and at the same time have high spring forces for good electrical contact with a high contact force are achieved in that the contact spring lamellae are connected to the contact sleeve or to the casing wall of the contact sleeve in an interlocking manner at both axial ends.
A contact area with low levels of mechanical stress during compression of the contact spring lamellae is achieved in that the raised portions are of arcuate form.
Particularly advantageous grading of the plugging force when the contact sleeve is inserted into a mating plug is achieved in that the axial offset length between the raised portions of different or axially adjacent pairs of contact spring lamellae is 0.1 mm to 0.3 mm, in particular 0.2 mm, or a multiple thereof.
A symmetrical arrangement of the contact spring lamellae on the contact sleeve is achieved in that n, where n≥2, pairs of contact spring lamellae are formed on the contact sleeve, wherein the contact spring lamellae are at a distance from one another in the circumferential direction through an angle of 360°/(2*n).
The invention will be explained in more detail below with reference to the drawing, in which
The preferred embodiment, illustrated in
Each contact spring lamella 18 has a radial raised portion 20 which is of arcuate form. In the illustrated exemplary embodiment, the raised portion protrudes radially outward beyond the casing wall 12 of the contact sleeve 10. Each radial raised portion forms a contact area 22 at its highest point (indicated by dashed lines) which is designed to make electrical and mechanical contact with a mating connector. In the illustrated exemplary embodiment, the contact areas 22 are of rectangular form and extend substantially at a right angle to the center longitudinal axis 14. The raised portions of a pair of radially opposite contact spring lamellae 18 are located on a straight line 24 which intersects the center longitudinal axis 14 at a right angle.
According to the invention, the raised portions 20 or contact areas 22 of different pairs of contact spring lamellae 18 are at a distance from one another or offset by a predetermined axial offset length 26 in the axial direction with respect to the contact sleeve 10. In the present example according to
In the illustrated exemplary embodiment, the contact sleeve 10 is in the form of a stamped and bent part and accordingly has a joining slot 28. Furthermore, the contact sleeve 10 is produced from an electrically conductive and spring-elastic material, so that the contact spring lamellae 18 can be deflected in an elastically resilient manner. During insertion of the contact sleeve 10, as illustrated in
When the contact sleeve 10 is inserted into the mating connector 32, the contact spring lamellae 18 are therefore deflected radially inward, this leading to a corresponding required plugging force which has to be overcome during insertion of the contact sleeve 10 into the mating connector 32. Since, according to the invention, the raised portions 20 are arranged in a manner axially offset in relation to one another, this required plugging force is reduced.
The plugging process will be explained below with reference to
In
In
Therefore, as a result, owing to the axially offset arrangement of the raised portions 20 of the pairs of contact spring lamellae 18 over the entire axial plugging path, a reduced plugging force is produced in comparison to a plug-in process in which all of the contact spring lamellae 18 of all of the pairs of contact spring lamellae 18 have to be deflected radially inward at the same time.
The predetermined axial offset length 26 is, for example, 0.1 mm to 0.3 mm. In the illustrated exemplary embodiment, the axial offset length 26 has a value of 0.2 mm.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2016/000336 | 2/26/2016 | WO | 00 |