Patent Application
20050233634
The invention concerns a crossbridging member for electrical terminals which are disposed adjacent to one another in a row, such as, e.g. series terminals which are arranged in a row one after the other on a mounting bus.
It is known to provide the current bus of the terminals with connector receptacles, which are positioned centrally symmetric to a common plane of connector receptacles which extends in the direction of the row of terminals. This connector receptacle plane in the usual case runs in a so-called “bridging shaft”, which is formed constructively in the housings of insulating material for the terminals in the row arrangement.
The bridging members are produced as multiple bridging members, i.e., they possess two or more connecting pins which extend but away from the bridge head of the bridging member like a comb and are centrally symmetric to a common comb extension plane, whereby the comb extension plane is equally covered when the bridging member is plugged into the connector receptacle plane of the terminals.
The bridge head of the bridging member is protected by isolating it by means of insulating material.
In the common connector receptacle plane of the terminals arranged in a row, it is also possible and known to bridge gaps, e.g., by means of a bridging member, in which a central connecting pin is broken away at a break-off site, so that the terminal lying thereunder in the terminal arrangement is skipped over by means of such a modified bridging member.
In the case of current bridges employing the known bridging members, problems may occur when the manufacturing tolerances are not maintained for the individual terminals or when relative displacements occur within an arrangement of terminals in a row next to one another, e.g., as a consequence of fairly large tensile forces on the conductor or as a consequence of other forces acting on individual or adjacent terminals, by which means, their current-bus connector receptacles may be moved out of the common connector receptacle plane of the terminal arrangement.
These possible tolerance inaccuracies and relative shifts can cause a weakening of the contact force and thus a weakening of the current transfer between connecting pins and the current bus in the “connecting pin/connector receptacle” contact system, in particular, when the bridging member with its connecting pins is a stiff punched-out part and the connector receptacles in the current buses are formed as spring-loaded connector receptacles (e.g., as externally spring-loaded connector sockets). In such a case, the possible tolerance inaccuracies and relative shifts may be directed against the spring force of the spring-loaded connector receptacle, which is usually subjected to a prestress, so that the connecting pin is not pressed with the necessary contact force against the contact bearing surface of the current bus when the bridging member is plugged in.
The object of the invention is to avoid this endangering of the electrical contact security between the bridging-member connecting pins and the connector receptacles of the current buses and to develop a “connect pin/connector receptacle” contact system, which assures a continually sufficient electrical contact security even in cases of possible tolerance inaccuracies and relative shifts in the arrangement of terminals arranged in a row next to one another.
This object is solved according to the invention in that a sleeve of insulating material is formed starting from the insulating material of the bridge head of the bridging member for each connecting pin of the bridging member, and this sleeve extends in the axial direction around the connecting pin in such a way that between the connecting pin and the sleeve of insulating material an inner free space is present and that the connecting pin has a material constriction (=a material weak spot) inside the sleeve of insulating material and at a distance to the open end of the sleeve of insulating material, whereby the free space of the sleeve of insulating material around the connecting pin is dimensioned such that the free end of the connecting pin can execute a pivoting and/or rotational movement around the material constriction.
The teaching of the invention contains several advantages.
Named as a first advantage is the fact that the connecting pins of the bridging member can execute an equilibrating movement in a type of “pendulum swing” for the case when tolerance inaccuracies and/or relative shifts of individual terminals in a row arrangement of terminals require this. This is true even when the bridging member is manufactured as a low-cost, punched-out part and its material in fact possesses good electrical conductivity, but has only small elastic deformation properties. The possibility of adapting and equilibrating inaccuracies and shifts in the “connecting pin/connector receptacle” contact system according to the invention is essentially achieved only by the material constriction (=material weak spot) of the material of the bridging-member connecting pins in combination with the free space, which surrounds the connecting pins in the insulating sleeves, whereby it is advantageous to select the position of the material constriction in the depth of the sleeve of insulating material and in the vicinity of the bridge head of the bridging member, in order to maintain as small as possible the forces which are triggered and which must act on the free end of the connecting pin in order to carry out the equilibrating movements.
Another advantage of the invention is produced from the free space, which is formed inside the sleeve of insulating material that surrounds each connecting pin, between the sleeve of insulating material and the metal of the connecting pin, whereby in an advantageous manner, the open end of the sleeve of insulating material can be guided up to the vicinity of the current-bus connector receptacle of the respective terminal when the bridging member is plugged in.
The creep and air gaps between adjacent bridging-member connecting pins conducting different electrical potentials are considerably improved by this measure. This neighboring situation of differing electrical potentials is often encountered between the connecting pin of one bridging member on the end side and the end-side connecting pin of an adjacent plugged-in bridging member in row arrangements of terminals, when the two bridging members conduct different electrical potentials.
Another essential advantage of a bridging member according to the invention concerns its applicability to provide bridging members with gaps in row arrangements of terminals. To produce gaps, as is known, one or more connecting pins is removed from the bridging comb of a bridging member. In the case of a bridging member according to the invention, this gap is produced by grasping with tweezers the outer free end of a connecting pin, which projects out of the sleeve of insulating material that surrounds the connecting pin and removing the pin by vigorous rotating movements of the connecting pin around its material constriction (=a material weak spot, which serves in this case as a break-off site). Then the empty sleeve of insulating material remains in its entire depth or in its entire length, preferably if the material constriction is positioned in the depth of the sleeve of insulating material in the vicinity of the bridge head of the bridging member.
If the entire depth of the empty sleeve of insulating material remains, this will considerably improve the creep and air gaps between the skipped-over current bus of a terminal and the bridge head of the bridging member in the region where the gap is bridged, so that gap bridgings are possible with high current intensities.
It should be understood that the drawings are provided for the purpose of illustration only and are not intended to define the limits of the disclosure. The foregoing and other objects and advantages of the embodiments described herein will become apparent with reference to the following detailed description when taken in conjunction with the accompanying drawings in which:
FIGS. 1 to 3 show a longitudinal section and two cross sections through a triple bridge;
The excerpt shown in
A current bus 14 is disposed in the housing of insulating material of the series terminals and fixed in position. It possesses two connector receptacles 19 and 16 (see also for this the top view onto the current bus 14 in
In order to assure this reliability of contact for all contact connections of “connecting pins/connector receptacles” of a bridging member, wherein the latter must be constructed, e.g, as an eight-member bridging member (i.e., with eight connecting pins) in a segment of corresponding size in a row arrangement of terminals, it is provided according to the invention to position each individual connecting pin 18 in a sleeve of insulating material 21, which surrounds the connecting pin but leaves a free space 22 for it, so that the pin can execute an equilibrating movement around its material constriction 23 in a type of pendulum swing which may be required if tolerance inaccuracies and/or relative shifts of individual terminals occur in the segment that is found in a row arrangement of terminals.
The connecting pin is removed by vigorous rotational movements of the connecting pin 25 around its material constriction 27, which serves in this case as the break-off site.
After removal of the connecting pin, a completely empty free space 28 remains in the sleeve of insulating material 29, and the free space extends over the entire depth or over the entire axial length of the sleeve of insulating material, so that the creep and air gaps between the bridge head 30 of the bridging member and another electrical potential that may be present on the lower open end of the sleeve of insulating material are improved in such a way that gap bridgings are possible even with high current intensities by employing the bridging member shown in
While this disclosure has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure as defined by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2004 018 554.9 | Apr 2004 | DE | national |
