DD279571A5 - ELECTRICAL CONNECTION OR CONNECTION TERMINAL - Google Patents

Abstract

An electrical connection or terminal clamp has a sheet metal part (1) intended for pressing onto one end of at least one insulated electrical conductor, the sheet metal part (1) having an essentially U-shaped cross-section, on the inside of which there are webs running transversely with respect to the longitudinal axis of the connection or terminal clamp, which webs are bounded laterally by slots (2) located between them which are at least partially parallel. In order to be able to use the electrical connection or terminal clamp universally, especially for particularly thin varnish-insulated wires in a diameter range from approximately 0.05 mm to approximately 0.2 mm, the arrangement is designed such that the slots (2) (having a variable slot depth over their longitudinal extent) are constructed originating from a central region with the maximum slot depth (9) running continuously to regions (10) on the end sides, with the minimum slot depths. <IMAGE>

Description

For this 7 pages drawings

Field of application of the invention

The invention relates to an electrical connection or terminal, with a set for pressing at one end of at least one insulated electrical conductor sheet metal part of substantially U-shaped Querschnittsgostalt having on its inside transverse to the longitudinal axis of the connecting or terminal extending webs, the are bounded laterally by intervening, at least partially parallel grooves, and a method for their preparation.

Such electrical connection or terminals have the advantage that can be dispensed with an own stripping of the insulated electrical conductor ends. When pressing ("crimping") of the sheet metal part to the electrical conductor, preferably consisting of a layer of lacquer insulation layer is pierced in places or removed, so that a secure electrical connection between the connection or terminal and the electrical conductor comes about, at the same time a stable mechanical attachment In practice, problems arise in particular when these connecting or connecting terminals for very thin, in particular enamel-insulated copper or aluminum wires in the diameter range from 0.05 mm to about 2 mm There is the danger that either these thin conductor when pressing the sheet metal part experience an inadmissible and still undefined local Durchrnesserschwächung that leads to breaking or shearing the ladder or that there is no secure electrical connection Also, the electrical connection terminals may occasionally cease to function as a stable terminal pin for a screw terminal or the like terminal device. It must therefore consistently find different clamping sizes in this small diameter range, depending on the thickness of the respective insulating layer, use, which is undesirable.

Characteristic of the known state of the art

Thus, for example, from DE-OS 2300 629, an electrical connector is known, from which the invention proceeds and in which the arrangement is made such that on the inside of certain for pressing against the electrical conductor sheet metal part by milling, rolling, pressing or grinding are formed in one or more operations parallel ribs which are partially limited by inclined surfaces and otherwise separated by grooves. These ribs may be either perpendicular or generally oblique to the longitudinal axis of the connector, whereby a fish-herringbone-like or an arcuate arrangement of the ribs is possible. For the reasons mentioned, in the use of such an electrical connector for conductors in the diameter range of 0.05 to 2 mm, depending on Leiterdu.chmesser, different web heights, i. Groove depths are provided to prevent local squeezing of the conductor in the region of the ribs.

Basically, the same applies to a known from DE-OS 1565 987 electrical connection terminal for pressing against an insulated electrical conductor, in which the measures provided for on the inside of the sheet metal part intended for pressing ribs have a width which is substantially equal to or less than that Distance between bpnachbsrten ribs and the height of at least one of the ribs is equal to or greater than the distance between adjacent ribs uniJ equal to or greater than the material thickness of the remaining part of the clamp. Since the ribs extend exactly at right angles to the longitudinal axis of the clamp, when the sheet metal part is pressed against the insulated conductor, in particular in the areas of the parts of the high ribs which are exactly opposite one another, large diameter changes occur, as illustrated in FIG. 23 of this publication. Also, the proposal to form the ribs with different height approximately such that the rib height increases uniformly from the insertion of the wire to the other end, offers in very thin wires or electrical conductors no remedy, because just partially the thin conductor either not sure contacted or squeezed ,

Other electrical connection or terminals of this type use in the particular sheet metal part intended for machining, inwardly projecting claws or teeth (US-PS 3064 072). These claws, etc. are therefore not readily suitable for very thin electrical conductors, because they also lead to unpredictable local weakening of the conductor and also can not be made arbitrarily small, as would be required with respect to the small Leiterdui diameter. This is true even if - as known from US-PS 3265 807 - these claws in the form of small, the marginal edges of incorporated in the ölecr.teil grooves limiting rows of teeth are formed. In one known from GB-PS 820 243 electrical connection or terminal in the sheet metal part intended for pressing parallel, at right angles to the longitudinal axis of the terminal grooves are worked out, the boundary acts as a cutting edge for the insulation layer. In order to produce a secure separation of the insulating layer and thus a perfect electrical connection, the procedure is such that the pressing or crimping pressure in the attachment of the connection or terminal is designed to be variable on the electrical conductor over the length of the sheet metal part intended for pressing. In this way, in the deformation of the sheet metal part and the conductor, a longitudinal movement between these two elements is generated, which is conducive to a secure separation of the insulation layer. Since no limitation of the penetration depth of the webs present between the grooves in the plastically deforming conductor material is given when pressing the sheet metal part to the conductor, such connection and terminals for thin electrical conductors in the mentioned diameter range from 0.05 to about 0.15 or 0.2 mm is not readily usable. Also, in practice, it is difficult to produce an over the length of the sheet metal part to exactly prescribed extent changing contact pressure or crimping, which would have to be tuned on top of the conductor diameter and the thickness of the insulating layer on top of that.

Object of the invention

The aim of the invention is to avoid the deficiencies of the known solutions.

Explanation of the essence of the invention

The object of the invention is to provide an electrical connection or terminal of the type mentioned, which is particularly suitable for use in very thin insulated electrical conductors with an outer diameter lying in the range of about 0.05-0.2 mm, and thereby Ensures proper contact with stable mechanical connection these thin conductors, without having to keep or provided for each individual conductor diameter or each specific insulation layer density own Klemmentype or education on stock.

Furthermore, a method for producing such terminals is to be proposed.

To solve this problem, the electrical connection or terminal according to the invention is characterized in that over its longitudinal extent a variable groove depth having grooves, starting from a central region largest groove depth, are formed continuously extending to end-side areas smallest groove depth.

Due to the roughly curved course of the groove depth over the groove length is achieved that when pressing the U-shaped sheet metal part to the electrical conductor, the maximum penetration depth of the plastically deforming conductor material is limited to individual zones and does not extend around the entire conductor, in the limited zone of maximum penetration depth, reliable electrical contact occurs even with thick insulation layers, while the sheet metal partial regions of smaller groove depth applied to the other peripheral regions prevent circumferential circumferential weakening of the diameter, so that the mechanical stability and strength of the connection between the sheet metal part and the Conductor is not affected.

Advantageously, the grooves are designed to terminate at the end in the inner surface of the sheet metal part, wherein the grooves can be limited directly by the lateral edges of the sheet metal part. However, the arrangement can also be made such that between the grooves and the respective adjacent side boundary of the sheet metal part an un-grooved area is present, so that the thin conductor when pressing the sheet metal part in a peripheral area at all suffer from a weakening of the diameter leading plastic deformation.

In continuation of this idea, at least some of the grooves can be interrupted over their longitudinal extent by at least one narrow, ungrouted area, as it is also conceivable that at least two separate, strip-shaped adjacent grooves containing areas may be present between the opposite side boundaries of the sheet metal part.

In a preferred embodiment, the substantially parallel grooves are arranged obliquely to the longitudinal axis of the connection or terminals, whereby it is achieved that when pressing the U-shaped sheet metal part to the electrical conductor, the grooves extend obliquely to the axis of the electrical conductor, which means in that the electrical conductor is encompassed by the grooves and de ι between these webs approximately spiral-shaped. This is a further conservation of very sensitive conductors, given for example very thin aluminum wires. In a modified embodiment, the grooves may also be arranged in pairs crossing each other. If the grooves, as mentioned, each arranged in strip-shaped areas, the grooves of adjacent strip-shaped areas may be provided in pairs an obtuse angle including each other, which corresponds approximately to a herringbone pattern-like arrangement.

The pitch of the grooves on the groove length or the width of the sheet metal part suitably corresponds approximately to the groove width, so that when U-folded sheet metal part, the Nuten- and web areas on one leg of the sheet metal part with respect to the grooves and land areas on the other leg of the sheet metal part to a Thus, when pressing the sheet metal part, the material of the thin conductor always dodge into a groove opposite to a web; there are never two bridges to face each other.

The grooves advantageously have a substantially arcuate curved groove bottom in the flat sheet metal sheet metal part, wherein they are expediently delimited at their side edges with sharp edges. This groove training not only allows an accurate rational production with relatively simple means, but at the same time ensures a secure cutting of the insulation layer.

For the preparation of the new connection or terminals, a method may be used in which the sheet metal part of the terminals initially grooved and then bent in a U-shape, according to the invention proceeds such that the grooves in the flat sheet metal part by means of a continuous, multi-toothed cutting tool are milled. As a cutting tool can be used preferably a single or multi-threaded thread cutting tool.

In this way, it is not only possible to mill the grooves very accurately dimensionally stable, but it also results in a very efficient method of production, because each running from a circle cutting the tool automatically generate a circular arc shape of the groove bottom.

For the mass production of such connection or terminal clamps, it is expedient if a sheet metal strip is held in engagement with the rotating thread cutting tool and slotted at least in sections by the thread cutting tool, whereby the sheet metal strip is conveyed simultaneously in the belt direction and then the connection Due to the helical course of the teeth of the thread cutting tool, this automatically causes a feed of the sheet metal strip in its longitudinal direction

embodiments

In the drawings, embodiments of the subject matter of the invention are shown. Show it:

1 shows in each case a series of connecting or connecting terminals according to the invention, in three different forms of embodiment, in a perspective schematic representation;

Fig. 4: a terminal according to the invention, in a further embodiment, in a perspective schematic representation;

5 shows the sheet metal part intended for pressing one of the connecting or connecting terminals according to FIGS. 1 to 4, in the flat state, in the plan view and in the cutout, and in an enlarged view;

Fig. 6: the sheet metal part of Figure 5, taken along the lines Vl-Vl of Figure 5, in a side view. Fig. 7: the sheet metal part of Figure 5, taken along the line VII-VII of Figure 5, in a side view. T'g. 8: the sheet metal part according to FIG. 5, in the U-shaped bent state, in the cutout and on a different scale;

FIG. 9 shows the sheet-metal part according to FIG. 8, in the pressed-on state completely encompassing an electrical conductor, in section and in a plan view; FIG.

FIG. 10 shows a connection terminal according to FIG. 2, in the state pressed against two thin electrical conductors, in two different embodiments; FIG.

and Fig. 11: which embodiments, in a frontal view and on a different scale; Fig. 12: the arrangement of Figure 9, taken along the line XII-XII of Figure 10, in a plan view and on a different scale.

Fig. 13, the sheet metal part of a connection or connection terminal according to the invention, in three different Ausführungsforbis 15: men the groove arrangement, in each case in section and in a plan view.

In Figs. 1 to 4 four different embodiments of terminal or connecting terminals are illustrated, each of which has a substantially U-shaped curved scent part 1, which consists of a suitable metal sheet, for example, semi-hard Messingble-n, and in the flat state of is rectangular shape. The substantially U-shaped sheet metal part 1 in cross-section is provided on its inside with grooves 2 extending obliquely to the clamping longitudinal axis and intended for pressing (crimping) on a thin, insulated, electrical conductor not shown in FIGS ,

In the embodiment of Fig. 1, each of the U-shaped sheet metal parts 1 is connected to two opposing tabs 3, which are bent around the insulation of the conductor encompassing. This embodiment is also used for connection of at least one end face to be introduced into the screen part 1 thin electrical conductor with which a supporting this, protruding pin of a plastic bobbin or a plastic winding end of a transformer or a choke is taken, as for example in the DE-PS 22 48 158 is explained in detail. This embodiment of Figure 2 is without; the tabs 3 formed. In the embodiment of Figure 3, the illustrated U-shaped sheet metal parts 1 are integrally connected to a flat terminal block 4, which can also be used to attach the connection or connection terminals on an electrical device or on a circuit board use. In the embodiment of Figure 4, finally, a connecting eye 5 is formed on the U-shaped sheet metal part 1.

As is apparent from FIGS. 5 and 7, the parallel flankig limited grooves 2 are aligned parallel to each other in the flat lying f-.llechteil 1 cut such that between adjacent grooves 2 each also a parallelflankig limited ridge 6 stops. The grooves 2 are laterally limited at 7 sharp edges. They run transversely to the terminal longitudinal axis 8 of the connection or terminal, wherein the arrangement is made such that the grooves 2 are arranged obliquely to the clamping longitudinal axis 8 extending.

Each of the grooves 2 has a variable groove depth over its longitudinal extent in the manner to be taken from FIG. 6, such that the groove 2, starting from a central region 9 of largest groove depth, is designed to extend continuously to end regions 10 of the smallest groove depth. In the illustrated embodiment, the Nutnnboden 11 is arcuate curved, d. h., he lies on a 12 indicated arc.

The grooves 2 are formed endwise in the inner surface of the sheet metal part 1, wherein between the grooves 2 and the respectively adjacent side boundary 13 of the sheet metal part 1, an ungrouted region 14 is present (see also Fig.8). Alternatively, the grooves 2 could also leak directly on the side boundaries 13, whereby the ungrooved regions 14 come to be omitted, as indicated in Fig. 5 for the bottom groove 2 a. The groove width corresponds approximately to the width of the webs 6. However, it is also possible for the grooves 2 to be wider than the webs 6.

The given by the angle, which includes the longitudinal axes of the grooves 2 with the longitudinal Kiemmsnlängsachse 8, slope of the grooves 2 is selected over the groove length and the width of the sheet metal part 1 about the groove width accordingly. To connect two thin, for example, paint-insulated electrical conductors 15, the U-shaped sheet metal part in the manner shown in FIGS. 10,11 either double C-shaped or double U-shaped inflected (crimped). In this case, the conductors 15 are somewhat flattened in the manner resulting from the two figures, wherein they are simultaneously wrapped on their outside by the grooves 2 over a range of approximately 180 °. In Fig. 10, the relatively thin wires are held by the folded end edges 13 in abutment against the grooves encircling them, while in Fig. 11, the somewhat thicker conductors 15 are held by the ungrouted strip-shaped edge regions 14. In any case, the conductors 15 but related to the Fig. 10,11 - only with their underside on the deep groove areas, while on their top, the groove depth of the opposite folded sheet metal parts is already very low and to the inside opposite sides of the conductor on Zero expires. This means that in the deformation, the conductor material flows plastically to a greater extent only in the lower deeper groove areas, while in the overhead low groove areas the webs 6 are now correspondingly pressed slightly into the conductor material. Since the grooves 2 and the webs 6 in the manner shown in Fig.8 way with pressed sheet metal part 1, the conductors 15 helically wrap obliquely to the longitudinal axis clamp 8, results for each conductor 15 in the sectional view through the area of greatest plastic deformation of the conductor material in the Principle in Fig. 12 illustrated arrangement in which a depressed into the conductor material web 6 on the opposite side of a groove portion 2 is assigned. This avoids the occurrence of regions in which the conductor material is cut off in a ring shape by a web lying in a plane. The displaced by a web 6 material can escape in the opposite groove area.

Of course, each of the terminal or connection terminals described can be used not only in the manner shown in Figs. 10,11 for beaonders thin or slightly thicker conductor 15, which are each crimped in pairs in a sheet metal part 1. It is always possible to crimp only a thin conductor 15 in the manner described with the sheet metal part 1 or to use the sheet metal part 1 for connection to a much thicker conductor. In the latter case, the sheet metal part 1 surrounds this (relatively thick) conductor simply over a circumferential region of about 360 °, wherein it is pressed inward in the region of the seam formed by the opposite side edge edges 13, as is known per se.

In the embodiment shown in FIGS. 5 to 8, the grooves 2 extend substantially over the entire width of the sheet-metal part 1 except for the non-grooved regions 14, the point having the largest groove depth in the region 9 in the middle between the two side boundaries 13 lies. In contrast, 13.14 embodiments of the sheet metal part 1 are illustrated in which the grooves 2 are interrupted over their longitudinal extent each by a narrow, ungrouted area 16 in Figs .. The grooves 2 extending on both sides of the ungrooved (middle) region 16 are shown in each case in two separate, substantially strip-shaped regions 17, which are indicated by dashed lines in FIGS. 13, 14.

Whereas in the embodiment according to FIG. 13 the grooves 2 are arranged running parallel to one another such that their longitudinal axis intersects the clamping longitudinal axis 8 at the same (obtuse) angle, in the embodiment according to FIG. 14 in the strip-shaped regions 17 each in pairs corresponding opposite grooves with their longitudinal axes an obtuse angle with each other, so that there is a fischgrätmusterähnlinhe arrangement.

In Fig. 15, an embodiment is illustrated in which the obliquely to the clamping longitudinal axis 8 extending grooves 2 each arranged in pairs crossing each other "ind, wherein the groove length approximately equal to that of the embodiment of FIGS. 5,8.

The point largest groove depth in the area 9 is in the embodiments of FIG. 13,14 respectively on the center line of one of the strip-shaped areas 17, while in the embodiment of FIG. 15 it comes to lie on the clamping longitudinal axis 8.

In principle, it would also be conceivable to arrange a larger number of strip-shaped areas 17 containing grooves 2 over the width of the bending part 1, if this proves to be necessary or advantageous for the individual application.

In the production of the connecting terminals or terminals exemplified in Figs. 1 to 4, the procedure is such that in a sheet metal strip, the grooves 2 are milled by means of a rotating multi-toothed cutting tool to subsequently punched out of the sheet metal strip, the connection or terminals and their their Grooves 2 containing sheet metal part 1 are bent in a U-shape.

Claims (14)

An electrical connection terminal having a sheet metal part of substantially U-shaped cross-sectional shape, adapted to be pressed against one end of at least one insulated electrical conductor, having webs extending transversely to the longitudinal axis of the connection or terminal on its inside, at least partially parallel grooves are laterally delimited, characterized in that over its longitudinal extent a variable groove depth grooves (2), starting from a central region largest groove depth (9), steadily extending to end-side regions (10) smallest groove depth, are ausT ibildet , 2. Clamp according to claim '(, characterized in that the grooves (2) are formed end-end in the inner surface of the sheet metal part (1). 3. A clamp according to claim 2, characterized in that between the grooves (2) and the respective adjacent side boundary (13) of the sheet metal part (1) an ungrouted region (14) is present. 4. A clamp according to claim 1, characterized in that at least some of the grooves (2) are interrupted over their longitudinal extent by at least one narrow, ungrouted region (16). 5. A clamp according to claim 1, characterized in that between the opposite side boundaries (13) of the sheet metal part at least two separate, strip-shaped juxtaposed grooves (2) containing regions (17) are present. 6. A clamp according to claim 1, characterized in that the substantially parallel grooves (2) are arranged obliquely to the longitudinal axis (8) of the connecting or terminal running. 7. A clamp according to claim 6, characterized in that the grooves (2) are arranged in pairs crossing each other. 8. A clamp according to claims 5 to 7, characterized in that the grooves (2) of adjacent strip-shaped areas (17) in pairs, a blunt hints! enclosing each other, are arranged. 9. A clamp according to any one of claims 5 to 8, dadu: ch characterized in that the pitch of the grooves (2) over the groove length or the width of the Bleohteiles (1) corresponds approximately to the groove width. 10. A clamp according to claim 1, characterized in that the grooves (2) in the flat-flying sheet metal part (1) have a substantially circular arc-shaped groove bottom (11). 11. A clamp according to claim 1, characterized in that the grooves (2) are defined by sharp edges on their side edges. 12. A method for the production of connection or terminals, wherein the sheet metal part of the respective connection or terminal initially grooved and then U-shaped is bent, characterized in that the grooves are milled into the flat sheet metal part by means of a continuous, multi-toothed cutting tool , 13. The method according to claim 12, characterized in that a single or multi-start thread cutting tool is used as the cutting tool. 14. The method according to claim 12, characterized in that sin metal sheet strip held with the rotating thread cutting tool engaged and thereby grooved from the thread cutting tool at least partially and simultaneously conveyed in the tape longitudinal direction and that subsequently punched out the connection or terminals of the grooved belt and bent become.