DD143129A5 - ELECTRICAL CONNECTOR AND DEVICE FOR FINAL CONFIGURATION FOR INSULATED LADDER - Google Patents

Description

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Electrical connector and device for completion manufacture ; for insulated conductors.

A field of application of the invention

This invention relates to solderless electrical connections, and more particularly to a novel electrical connector including a contact for forming a crimped insulation piercing electrical terminal and termination device used to make such a terminal.

Characteristic of the known technical solutions

In recent years, an increasing number of developments have been made in the communications, data processing, and transportation industries requiring electrical terminals that provide reliable solderless connections to insulated electrical conductors. This need may have been greatest in the telecommunications industry where miniaturized high density tape connectors are widely used. Plugs of this general type are described in U.S. Patent Nos. 3,867,005, 3,902,154 and 3,926,498. Because of the large number of single conductors terminated in these plugs and the small spacing between the individual contacts, it is difficult to make reliable solder joints, and maintenance and care is time consuming and expensive. For these reasons, the insulation has been made by drilling contacts designed for use in ribbon connectors that have generally found favorably when used to terminate insulated conductors with solid wire cores. Unfortunately, because of the stringent standards in the industry, there has been an almost negligible change in the

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Demand resistance, the insulation piercing ribbon connector for use with ladder conductors proved to be unacceptable. Experience has shown that the tensile forces acting on the conductors as well as the cold flow of the insulation surrounding the core, a movement of the individual wires of the wire core and a Um-. Alignment within the insulation piercing contacts causes, resulting in changes in contact resistance. Therefore, in insulated conductors with strand core, ribbon plugs with solder termination are still used.

Object of the invention . - ·,

The aim of the invention is to provide an electrical connector that ensures a reliable solderless electrical connection for an insulated conductor. In addition, the solderless termination should be realized with the preassembled in the plug electrical contact.

Explanation of the essence of the invention

The invention has for its object to develop an electrical connector with a device for the effective and reliable production of a conclusion for insulated conductors with both solid core and stranded core in a insulation piercing contact, which does not require a soldering operation.

In one embodiment of the invention, the electrical connector generally includes an insulative insert, a plurality of electrical contacts, and devices that provide access to the contacts to form the crimped insulation-piercing termination. The contacts

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each include a closure member having opposed side walls which are mounted in a cavity of the insert. The access device includes a passageway in the insert into which a crimping tool is inserted which is used to deform the sidewalls of the contact terminals and secure the conductors in the termination position within the contacts.

The insulating insert includes a partition defining the contact cavities. The access is in a passage formed in the partition. The subdivision consists of several elongated, upright partitions. The passage is a slot that runs across the partitions. The contact closure member includes a bottom wall which is integral with the side walls and has an insulation piercing device which is generally arranged to coincide with the access in the insert. The contact termination member consists of an elongated channel having continuous side walls along the entire channel, the side walls also having opposed, inwardly projecting insulation piercing devices located remotely from the access devices of the insert. The insulation piercing device of the bottom wall consists of an upstanding insulation piercing profile made in one piece with the bottom wall. The contact termination member includes two pairs of inwardly projecting insulation piercing devices, which are integral with the sidewalls and located apart from the transverse slot and on opposite sides of the slot. The insert contains two rows of cavities that are outside the opposite

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Face of the insert face each other, and a slot in each of the opposite surfaces, which extends transversely through the cavities. The sidewalls project upwardly into the transverse slot, but terminate below the outermost surface of the upstanding walls, whereby a crimping tool can be inserted into the slot to deform the portion of the sidewalls adjacent the slot to provide insulation piercing contact with the slot the conductors are made, which are arranged in the contact closure parts.

The side walls of the closure part generally have the same height.

The invention also includes a novel device used to connect insulated conductors, solid core and strand core to the plug by means of a crimped, insulation piercing termination. The apparatus generally includes a forked split end cap containing an insertion portion and a power supply. The insertion member has an elongated and generally planar end surface for gripping a longitudinal portion of the conductor and pressing it against the termination portion of the contact so as to pierce the insulation and establish electrical contact. The crimp has a termination surface with a device for cutting off portions of the contact sidewalls and for folding the sidewall portions over the conductor to mechanically hold the conductor in insulation piercing electrical contact with the contact termination portion.

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embodiment

The invention will be explained in more detail with reference to the accompanying drawings. In the drawings:

Pig. Figure 1 is a side elevational view of an electrical connector embodying features of the invention and showing the individual conductors of a multi-conductor electric cable terminated therein;

Fig. 2: a partial perspective view of the plug of Pig. 1, with parts broken away to illustrate the crimp punch termination achieved with the invention;

Fig. 3i is a partial sectional view illustrating the sequence of steps performed to achieve the desired crimp punch connection;

Fig. 4 is a perspective view illustrating a preferred end tool according to the invention;

Fig. 5i is a plan view of the terminal member of a preferred contact element used in the plug shown in Fig. 1; and

6: a perspective view of the contact element of FIG. 5 »

Referring now to the drawings and in particular to Fig. 1, an electrical conductor 10 is shown with individual insulated conductors 12, each through the

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electrical contacts of the plug are completed. The plug 10 is a ribbon plug and includes an insulator insert 14, a plurality of electrical contacts 16 mounted in the insert, and a metal cap 18 in which the insert and the contact assembly are housed. A detailed description of the construction and puncture of ribbon connectors and their components is given in U.S. Patent Nos. 3,867,005 and 3,926,498, the disclosures of which are incorporated herein by reference.

The insert 14 includes a plurality of elongated contact receiving cavities 20 and an access path in the form of a slot 22 which extends transversely to the cavities 20. The slot 22 provides access to the electrical contacts 16 to allow the crimp punch termination of the conductors 12, as described in more detail below.

In Pig. 2, the assembly comprising the insert 14 and the contacts 16 is shown in more detail. The insert includes a plurality of partitions or upstanding barriers 24 which form the sides of the contacting cavities 20. Each contact 16 has an active contact portion 26 adapted to be electrically connected to a mating contact and a termination portion 28 for making electrical and mechanical contact with the insulated conductors 12. In the illustrated embodiment, the end portion 28 of each contact is grooved, has a bottom wall 30 and opposing side walls 32 and 34, and includes insulation piercing devices for electrically and mechanically urging an inserted conductor into the channel Make contact.

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According to the invention, the insert 14 is designed so that the squeezing of the closure member 28 to the contacts 16 mounted in the plug is possible. To accomplish this, the slot 22 is formed in each divider wall 24 to provide access for a crimping tool. The slot 22 need not extend to the bottom of the cavity 20, but must terminate at a point below the top of the sidewalls 32 and 34 of the contact termination 28. In other words, the sidewalls 32 and 34 project up into the slot 22 into it. As shown in FIG. 3, the crimping tool is inserted into the cavity 20 along a path generally perpendicular to the closure member 28 and deforms a portion of the sidewalls 32 and 34 coincident with the slot 22 to form the conductor 12 in FIG to note the final position ·

A preferred arrangement for the closure member 28 is shown in Fig. 3, 5 and 6. According to this implementation, the side walls 32 and 34 have conventional insulation piercing stools or detents 36, the construction and function of which are well known in the art. In addition, the termination portion 28 of the contact includes another insulation piercing profile in the bottom wall 30. In the illustrated embodiment, the profile is an upright cone 37. The sidewalls also have cantilevered offset edges 38 forming an insertion for the crimping tool. The latches 36 are longitudinally disposed on the side walls 32 and 34 away from the slot 22 of the insert 14, and their function and operation remain substantially the same as with the previously used connectors. The cone 37 and the top edges 38 are arranged so that they coincide with the slot 22, they

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serve to improve both the mechanical and the electrical properties of the termination. When the conductor is pressed into the terminal part of the contact, the cone 37 pierces the insulation of the conductor and engages in the conductor core. Likewise, when the walls 32 and 34 are deformed by the crimping tool, the edges 38 pierce the insulation of the conductor and also engage the conductor core. Thus, by means of the detents 36> of the cone 37 and the upper edges 38, in the illustrated embodiments, the electrical contact is produced on the sides, top and bottom of the conductor. In addition, the mechanical fixation of the conductor in contact is enhanced, and the opportunity for displacement even of strand core conductors is thereby minimized.

A preferred device, a termination tool, is in Pig. 4; it has a fork-shaped split end cap 40 with separate insertion and crimping parts 42 and 44, respectively. The insertion part 42 has a generally flat end surface 46 for gripping the conductor and pressing it onto the termination part 28 of the contact 16 so that electrical contact occurs will be produced. The crimp member 44 has a specially shaped end surface 48 having means for cutting off portions of the contact sidewalls 32 and 34 and devices for squeezing or folding these cut portions inwardly onto the conductor. In the illustrated embodiment, the cutting devices are curved edges 50 which shear the sidewalls of the contact as the tool is inserted into the cavity 20, and the squeezing devices are the swept surfaces 52 that meet at a central apex 54. It will be appreciated that when the insertion tool is fully inserted into the cabbage

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space 20, the surfaces 52 fold the cut portions of the sidewalls 32 and 34 over and into the conductor thereby crimping the contact and conductor into a solid, insulation piercing termination.

In a conventional ribbon connector, up to 25 conductors are terminated on each side of the connector by 25 separate contacts. Each conductor is brought to the termination part of a corresponding contact and then terminated by means of a suitable termination tool. The sequence of steps used to make a crimp punch termination with the plug and tool of the invention is shown in FIG shown. After the conductors have been brought to the corresponding contact termination parts 28, the tool guide head 40 presses each conductor into the termination part and then squeezes the contact on the conductor. Since the tool displaces relative to the connector during each insertion operation (from the right in Fig. 3) to the left), the insertion part 42 first fits the conductor in the contact and brings him for the subsequent introduction of the crimping 44 in the correct position. As can be clearly seen in Figure 3, the crimp member 44 extends laterally beyond the side walls 32 and 34 of the contact, thereby requiring an access path or slot 22. The depth of the Schlitse3 22 must be sufficient to allow for the complete insertion of the pinch 44 to the side walls 32 and 34 properly sheared and the sheared T _e ± le completely over the conductor and crimped into it it able v /.

It goes without saying that various changes

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These modifications and modifications may be made without departing from the spirit and scope of the invention and without diminishing its merits.

Claims (11)

212 274 1 ♦ Electrical connector for connecting electrical circuits containing insulated conductors, characterized by: an insulating insert containing multiple contact cavities; a plurality of electrical contact elements, each having a closure member with opposite side walls disposed in one of the cavities; Accesses formed in the insulator insert and providing access to the sidewalls whereby a crimping tool may be inserted into the accesses to deform the portions of the sidewalls adjacent the access and to secure the conductors in the termination position in the contact termination portions. 2. The electrical connector of item 1, characterized in that the insulator insert includes a partition defining the contact cavities, and the access is in a passage formed in the partition. 3 «Electrical connector according to item 2, characterized in that the subdivision consists of a plurality of elongate, dividing dividing walls and that the passage is in a slot which extends transversely through the partitions. 4.10.1979 55 306/13 protrude, but below the outermost surface of the upstanding walls, whereby a crimping tool can be inserted into the slot to deform the part of the sidewalls adjacent to the slot to provide insulation piercing contact with the conductors inserted into the slot Contact closure parts are arranged. 4.10.1979 55 306/13 which is generally arranged so that it coincides with the access in the insert. Electrical connector according to item 1, characterized in that the contact closure part comprises a bottom wall which is made in one piece with the sidewalls and comprises an insulation piercing device. 212-274 4.10 * 1979 55 306/13 invention claim Electrical connector according to item 1, characterized in that the contact termination part consists of an elongated channel with continuous side walls along the entire channel, the side walls also having opposed, inwardly projecting insulation piercing devices located remotely from the access devices of the insert. 6. Electrical connector according to item 4, characterized in that the insulation piercing device of the bottom wall consists of an upstanding, insulating perforated profile, which is made in one piece with the bottom wall. Electrical connector according to item 5, characterized in that the contact termination part comprises two pairs of the inwardly projecting insulation piercing device, which are integral with the sidewalls and located apart from the transverse slot and on opposite sides of the slot. 8. Electrical connector according to item 1, characterized in that the insert contains two rows of cavities facing each other outside the opposite faces of the Einsatzstueks, and a slot in each of the opposite surfaces, which extends transversely through the cavities. 9 · Electrical connector according to item 3 *, characterized in that the side walls are facing upwards in the transverse slots 12 274 10. Electrical connector according to item 9, characterized in that the side walls of the closure part generally have the same height. 11. An apparatus for terminating an insulated conductor in an insulation piercing terminal portion of an electrical contact, said termination portion being disposed in the cavity of a male insert and consisting of an elongate groove having sidewalls and a bottom wall having an upstanding insulation piercing device; the tool is characterized by: a fork-shaped split end cap having an insertion portion and a crimp portion, the insertion portion having a generally planar end surface to engage a longitudinal portion of the conductor and the conductor and termination within the cavity into proper position for subsequent insertion Squeezing operation, and wherein the squeeze member has a closure surface with means to cut off portions of the side walls at a location coincident with the insulation piercing devices. and means for squeezing the side wall parts onto the conductor and thereby fixing the conductor in the insulation piercing and electrical contact with the contact termination part. "Seifon drawings