Electrical Connecting Device

Abstract

This invention includes a socket contact of sheet metal, which is formed to a tubular configuration from a flat piece having a malleable portion at one end and a resilient portion at the other. The malleable portion is crimped to an adjoining wire, while the resilient portion provides a spring force for gripping a mating pin. The latter element may be permanently mounted in the connector and extend through a sealing member such as rubber or glass. The pin extends outwardly for insertion into the socket contact of an adjoining connector section.

Description

BACKGROUND OF THE INVENTION

1. The Field of the Invention

This invention relates to an electrical connector.

2. The Prior Art

There is a continuing need for electrical electrical connecting devices, particularly where the connectors must meet the rigid performance standards existing in the aerospace field. Problems are accentuated by the trend toward further miniaturization and the small size permitted the electrical connecting devices.

In these connectors, it is desirable to attach the wires to the contacts by crimping. This is a reliable and simple means of forming an attachment, requiring neither the skill nor the time necessary where the contacts are soldered to the wires. Mating contacts also require some resilient means in order that a firm engagement can be made between a pin contact and a socket into which it is inserted to accomplish an electrical connection. Therefore, on the one hand, for a crimped connection to a wire, the contact should be malleable in order that it can be deflected to grip the wire. On the other hand, resilience is needed where the pin and socket must be held together in firm engagement. Therefore, a crimped-type socket contact has required construction from a material having malleability, plus the inclusion of auxiliary spring elements for assuring that the mating pin will be appropriately engaged to accomplish the electrical connection. The malleable material for crimping will not provide the requisite resilience for firm contact engagement, so that the complexities and expense of the added spring arrangements have been necessary.

In hermetic connectors, there has been in the past no satisfactory means of providing crimped-type contacts. These connectors normally include glass inserts to accomplish the hermetic seal. This is done by fusing the contacts in the glass so that no leakage will take place around them. The contacts then become permanently and nonremovably fastened in the electrical connector. It is necessary, therefore, to solder each wire to its contact so mounted. This is a very slow and laborious operation, particularly for connectors of smaller sizes, requiring a high degree of skill. It presents even more of a problem from the servicing standpoint as the contacts cannot be taken from the connectors. It is necessary when separating a wire from the contact to melt the solder joint so that the wire can be removed. With the large bundle of wires entering an ordinary connector, and the lack of accessibility to inner portions of it, the joints of many additional wires must be melted and the wires removed in order to provide access to the one where the wire separation is needed. Following this, all the wires must be resoldered to their contacts.

SUMMARY OF THE PRESENT INVENTION

The present invention provides an improved arrangement whereby crimped-type contacts are able to provide a resilient force for engagement with mating pins. The invention also permits removable crimped contacts to be used with hermetic connectors. For all types of connectors, it provides a device of high performance and maximum reliability.

According to this invention, the socket contact is formed from a sheet metal piece made up of two sections welded together at their edges. One section is of malleable material, and the other is of resilient material. These are rolled to a tubular form, with the resilient end being split in order that it may provide opposed resilient jaws for gripping a pin inserted within it. The malleable end is attachable to the wire by a simple crimping operation. The contact may be provided with an internal stop for limiting the inward movement of the wire, and an external shoulder for use in positioning the contact in a connector.

The socket contact may mate with an elongated pin that extends between it and another socket contact. This pin is secured in the connector, and for hermetic connectors it is fused in the glass insert, where it is effectively sealed. Only the pin, therefore, is permanently attached to the connector, while the socket contact is readily removable from it. Forwardly inclined spring tabs are used in the retaining arrangement for the contact, permitting it to be removed and inserted from the rear. The pin so secured can be mated with conventional socket contacts. Conversely, the sheet metal socket contact of this invention can be joined to a conventional pin contact rather than the permanently mounted pin.

An object of this invention is to provide an improved electrical connecting device.

Another object of this invention is to provide a contact capable of resiliently engaging a mating electrically conductive member, while also being attachable to a wire by crimping.

A further object of this invention is to provide sealed connectors, including hermetic connectors, having removable contacts.

Yet another object of this invention is to provide an electrical connecting arrangement meeting highest performance standards, yet which is producible rapidly and at a low cost.

A further object of this invention is to provide an electrical connecting device facilitating servicing and maintenance.

An additional object of this invention is to provide an electrical connector device having versatility in the manner in which it may be mated with an adjoining part.

These and other objects will become apparent apparent from the following detailed description taken in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS:

FIG. 1 is a perspective view of a socket contact in accordance with this invention;

FIG. 2 is an enlarged longitudinal sectional view of the contact, taken along line 2--2 of FIG. 1;

FIG. 3 is a longitudinal sectional view taken along line 3--3 of FIG. 2;

FIG. 4 is a transverse sectional view taken along line 4--4 of FIG. 3;

FIG. 5 is a view similar to FIG. 2, but with the contact attached to a wire by crimping;

FIG. 6 is a perspective view of malleable and resilient strips used for producing the contact;

FIG. 7 is a perspective view of the strips after joining at their edges;

FIG. 8 is an elevational view illustrating the rolling of the strips to reduce their thickness;

FIG. 9 is a perspective view of the blank for forming the contact cut from the strips;

FIG. 10 is a perspective view of the blank after cutting a slot and bending the stop tab;

FIG. 11 is a perspective view after the blank has been rolled to a tubular shape;

FIG. 12 is a longitudinal sectional view of the receptacle of a hermetic electrical connector made in accordance with this invention;

FIG. 13 is a fragmentary sectional view of the receptacle, illustrating the manner in which the contacts may be removed;

FIG. 14 is a longitudinal sectional view of a plug for mating with the receptacle of FIG. 12;

FIG. 15 is a fragmentary longitudinal sectional view showing the receptacle and plug in the mated position;

FIG. 16 is a longitudinal sectional view of the invention as applied to a connector which is not hermetic; and

FIG. 17 is a fragmentary sectional view of a connector in which the socket contact of this invention is mated with a conventional pin contact.

DESCRIPTION OF THE PREFERRED EMBODIMENT:

A socket contact 10 made in accordance with this invention, as may be seen in FIGS. 1, 2, 3 and 4, includes a rearward cylindrical barrel portion 11 and a slightly frusto-conical forward end portion 12 that is convergent outwardly. The latter part of the contact is provided with opposed longitudinal slots 13 and 14 so that it has opposed jaw sections 15 and 16. This end of the contact is adapted to receive a pin when in the mated condition for transmission of current between the contact and the pin. Intermediate the forward portion 12 and the rearward barrel portion 11 is a section 17 of enlarged diameter. This provides a substantially radial forward exterior shoulder 18 and a similar rearward shoulder 19. These shoulders are utilized in positioning the contact in an electrical termination device, as will be described below.

The barrel end 11 of the contact 10 is adapted to receive the end of a wire 20 stripped of its insulation 21, as seen in FIG. 5. With the wire end in the contact barrel, the latter portion is deflected inwardly by a suitable tool to provide undulations 22 bearing against the wire. This crimps the barrel 11 so that it is attached to the wire 20 and forms an electrical circuit with it. A tab 23 extends radially across most of the width of the contact at the inner end of the barrel 11. This acts as a stop that is engageable by the end surface 24 of the wire 20, limiting the distance the wire 20 can be inserted into the contact 10. This assures that the wire 20 remains within the barrel portion 11 of the contact and does not enter the forward section 12. Therefore, the end of the wire 20 will not interfere with a pin to be inserted into the end 12 of the contact when it is in service.

In order to function satisfactorily as a contact having the desirable crimped-type connection to a wire, it is necessary that the barrel portion 11 possess malleability. At the same time, the forward portion 12 requires resilience in order that the opposed sections 15 and 16 can act as springs bearing inwardly and gripping the surface of a pin inserted between them. In order to obtain these contrasting qualities, the contact 10 is made of one section A of malleable material, which is used at the barrel end of the contact, and an additional section B of spring material for the opposite end. The sections A and B are integrally attached together at a location adjacent the enlarged portion 17. Typically, the malleable material A may be brass, while the resilient material B is beryllium copper. It may be desirable for the latter portion to have a surface coating such as gold plating.

In obtaining material of this type, which is marketed under the trademark "Duo-Metal" by The Brush Beryllium Company, Reading, Penna., strips of the materials A and B first are prepared to a thickness somewhat greater than that desired for the gauge of the completed contact 10 (FIG. 6). These strips are welded together along their longitudinal edges to form a wider strip with the materials A and B integrally attached (FIG. 7). The assembled materials then repeatedly are passed through rollers, such as the rollers 25 and 26 shown in FIG. 8, reducing the thickness of the strip. Subsequently, it is cut to form the flat sheet metal blank of FIG. 9 that is used to make the contact 10.

The blank, which is of rectangular shape and predetermined dimensions, is provided with a cutout to serve as the slot 14 in the completed contact. Also, the stop tab 23 is cut and bent 90.degree. relative to the surface of the blank, as shown in FIG. 10. The blank then is rolled to a tubular shape, as seen in FIG. 11, bringing its opposite longitudinal edges 27 and 28 into adjacency. The intermediate portion 17 of enlarged diameter also is formed and the frustoconical shape imparted to the forward portion 12.

In addition, the edges 27 and 28 are joined in a suitable manner, such as by brazing, in the area of the barrel 11 of the contact. This provides a longitudinal brazed joint 29 along the barrel 11 so that the barrel is continuous around its circumference. This enables the barrel to be crimped to the end of the wire 20, irrespective of the rotational position of the barrel relative to the crimping tool. Without this attachment, in some relative rotational positions, the action of the crimping tool would cause the edges 27 and 28 to become displaced with respect to each other, and a secure connection to the wire would not be made. With the barrel end made as an uninterrupted tubular element, rather than being split, however, there is no difficulty in the crimping operation, and the wire always will be appropriately secured to the contact.

As shown in FIG. 12, several of the contacts 10 are associated in a completed section 30 of an electrical connector. In this arrangement, there is provided a rear-release type installation in which the contact can be both inserted and removed from the rearward end of the connector. This advantageous feature is present even though the connector illustrated is of the hermetic type normally requiring permanently mounted contacts and soldered connections of the wires to the contacts.

The connector section 30 shown in FIG. 12 is a stationary receptacle adapted to mate with a movable plug. The receptacle 30 includes a shell 31 having a flange 32 and a threaded exterior portion receiving a nut 33, which holds the receptacle to a mounting panel 34. The shell 31 is a tubular element within which are mounted various inserts. A glass insert 35 is included in providing the hermetic seal for the receptacle. On the forward side of the glass insert 35 (to the left as shown in FIG. 12) is a resilient rubber insert 36 that acts as an additional seal. A backing insert 37, also of resilient material, is positioned on the opposite, or rearward, side of the glass insert 35. The backing insert 37 is bonded to an insert 38 of substantially rigid dielectric material which, in turn, is bonded to an additional insert 39, also of such material. A nut 40 surrounds and engages the flange 41 of the rear insert 39, holding the insert assembly in the receptacle shell 31.

The inserts 38 and 39 together provide openings 42 parallel to the axis of the receptacle 30. The openings 42 are centrally enlarged to define spaced radial forward and rearward shoulders 43 and 44, respectively. In each of these openings is a retainer clip 45, which may be of the type shown in FIG. 14 of U. S. Pat. No. 3,158,424. The retainer clip 45 is a split tubular element received in the enlarged portion of the bore 42 so that it is prevented from axial movement by the shoulders 43 and 44. It is provided with two inwardly and forwardly extending resilient retainer tabs 46.

A contact 10 also is received in each of the openings 42 inside the retainer clip 45. The forward shoulder 18 of the contact 10 is adjacent the forward shoulder 43 of the opening 42, which thereby retains the contact against forward movement. The inner ends of the resilient spring tabs 46 are adjacent the rearward shoulder 19 of each contact 10, which prevents rearward movement of the contact. Thus, the contacts 10 are secured within the bores 42.

Continuations of the openings 42 are provided in the inserts 35, 36 and 37. Received within the openings in the latter inserts are elongated pins 48, the ends 49 and 50 of which are hemispherical. The central portions of the pins are molded into the glass insert 35. In this manner, the pins 48 are held in the receptacle 30, parallel to the axis, with hermetic seals formed around them. The peripheries of the pins 48 also are engaged by the resilient insert 36 to provide a further seal. The pins 48 extend forwardly beyond the inserts 36 and 37 into the open forward tubular portion of the shell 31. This provides longitudinally projecting pin ends for mating with adjacent socket contacts.

The opposite ends 50 of the pins 48 extend into the openings 42 and into the forward ends 12 of the contacts 10. There, each pin 48 is gripped by the opposed resilient jaws 15 and 16 of the contact 10, resulting in firm engagement with the pin and a low-resistance path for the flow of electric current. Entry of the pin 48 into the contact 10 is facilitated by the hemispherical end 50, which effectively spreads the jaws 15 and 16 slightly as the pin enters the receptacle. In their free positions, the spacing between the ends of the jaws 15 and 16 is less than the diameter of the pin 48 so that the jaws will grip the pins.

The receptacle 30 constructed in this manner is of the hermetic type, yet at the same time the contacts carried by the receptacle are joined to their wires by crimping and are insertable and releasable from the rear. Thus, the hermetic connector receptacle avoids the use of soldered connections and permanently attached contacts. It is a simple matter to introduce the contacts 10 into the openings 42 in the receptacle by a standard tool for engagement with the pins 48. This is accomplished by pushing each contact inwardly from the rearward end of the opening 42, advancing it to the position shown in FIG. 12. As this forward movement of the contact takes place, the forwardly and inwardly inclined spring tabs 46 are engaged and deflected outwardly by the enlarged portion 17 of the contact. After the rearward shoulder 19 of the contact has passed the forward ends of the spring tabs 46, they are free to snap inwardly behind the shoulder 19 to retain the contact in the receptacle.

Release of the contact also is readily accomplished from the rear through the use of conventional tooling. This operation is shown in FIG. 13, where a standard tubular releasing tool 52 is shown inserted into the rearward end of the opening 42, prying the spring tabs 46 outwardly beyond the periphery of the enlarged portion 17 of the contact 10. Preferably, as best seen in the enlarged views of FIGS. 2, 3 and 5, the corner 53 at the rearward end of the barrel 11 is beveled, which helps guide the tool 52 over the barrel without obstruction. With the tabs released, the contact is free for rearward removal merely by pulling outwardly on the wire 20. Thus, the hermetic connector provides for both rearward insertion and release. The contacts and their mountings are the same for both sections of the hermetic connector, simplifying the manufacture and use of the connectors.

The plug 54 shown in FIG. 14 is adapted to mate with the receptacle of FIG. 12. The mated position is illustrated in FIG. 15, where the plug 54 and receptacle 30 are held together by any suitable coupling mechanism. The plug 54 is not a hermetically sealed unit, as normally only the receptacle must have such characteristics, although the plug 54 could be made hermetic if desired. The plug 54 includes a shell 55, within which are inserts 56 and 47 of rigid plastic. These are provided with openings 58 similar to the openings 42 in the receptacle 30. Within each opening 58 is a retainer clip 45 engaging and preventing rearward movement of a contact 10. The shoulder 59 of the opening 58 limits forward movement of the contact in the plug.

The forward resilient insert 36 of the receptacle 30 is provided with forwardly extending frustoconical portions 60 around the pins 48. In the mated position of the plug and receptacle, the protruding portions 60 are received and compressed in the more sharply tapered frustoconical recesses 61 at the forward ends of the openings 58 in the insert 57 of the plug 54, forming an effective seal.

When the plug and receptacle are brought together, the ends 49 of the pins 48 slide into the forward end portions 12 of the contacts 10 in the plug. The opposing resilient jaws 15 and 16 of the contacts 10 in plug 54 resiliently bear against the peripheries of the pins 48, thereby providing completed electrical circuits. Thus, in accordance with this invention, the elongated pin 48 provides an intermediate element that transmits electrical current from one socket contact to the other. The pin 48 provides a member that is rigidly mounted in one section of the connector and is readily sealed, even hermetically with a glass insert.

The invention is adapted for use in connectors other than hermetic connectors, where, again, it offers advantages of low cost, simplicity and reliability. Standardization of parts and tooling for the full range of electrical connector types is made possible. As shown in FIG. 16, there is a plug 63 mated to a receptacle 64. The rigid plastic insert 65 of the plug 63 is provided with an opening 66 within which a retainer clip 45 and a contact 10 are received. Similarly, the insert 67 of the receptacle has an opening 68 with another retainer clip 45 and contact 10. An elongated pin 69 extends between the two contacts and is received in the outer ends 12 of each. The pin 69 in this instance is secured to the plug between the rigid insert 65 and a resilient insert 70 at the forward face of the plug. For this purpose, the pin 69 is provided with an enlarged portion 71 that defines an annular flange received in recesses in both the inserts 65 and 70. This provides a radially outwardly projecting element on the pin 69 which is retained by the inserts 65 and 70, and precludes axial movement of the pin. The flange portion 71 is secured when the inserts 65 and 70 are bonded together.

The contacts 10 also will mate satisfactorily with conventional pin contacts, rather than being utilized as discussed above where a single pin is used with a pair of socket contacts. As shown in FIG. 17, a contact 10 is mounted in an opening 73 in the insert 74 of a receptacle 75, held in place by a retainer clip 45. In the plug 77, however, a conventional pin contact 78 is held in the opening 79 in the insert 80 by means of the retainer clip 45. The contact 78 may be a machined part, rather than of sheet metal, including a hollow barrel 81, an enlarged intermediate portion 82 and a forward elongated pin end 83. The latter portion is received in the forward end 12 of the contact 10 in the receptacle, where, as before, the receptacle bears against the periphery of the pin and provides an electrical circuit.

For added versatility, the pins 48 or 69 of the previously described embodiments may be mated with conventional socket contacts rather than additional contacts 10.

Claims

I claim:

1. A hermetic electrical connector device comprising

a member defining an opening therethrough,

a substantially rigid insert of dielectric material received in said opening,

said insert having a forward end, a rearward end and at least one aperture extending therethrough,

a tubular contact in said aperture,

means positioning said contact in said aperture,

a wire extending into one end of said contact and connected thereto,

a glass insert in said opening beyond the opposite end of said contact,

an elongated pin extending through said glass insert,

said glass insert being fused to said pin so as to hold said pin rigidly and provide a hermetic seal therewith,

one end of said elongated pin extending into said opposite end of said contact,

the other end of said elongated pin extending outwardly beyond said glass insert for engagement with a mating electrically conductive device,

and an additional insert of resilient material in said opening adjacent said glass insert and extending around said elongated pin.

2. An electrical connector comprising

a tubular shell having a forward end and a rearward end,

a glass insert in said shell,

said glass insert having a forward side and a rearward side,

a plurality of spaced substantially parallel elongated pins, the central portions of said pins being received in said glass insert so that said pins are held rigidly and sealed with respect to said glass insert, one end portion of each of said pins extending outwardly from said forward side of said glass insert,

the opposite end portion of each of said pins extending outwardly from said rearward side of said glass insert,

a member of resilient material in said tubular shell engaging said forward side of said glass insert,

said member of resilient material having openings therethrough,

said one end portions of said pins extending through said openings in said member of resilient material and extending beyond said member of resilient material,

an insert of dielectric material in said shell adjacent said rearward side of said glass insert,

said dielectric insert having a plurality of first openings therethrough aligned with said pins,

a first contact in each of said openings,

each of said contacts having a forward end and a rearward end,

each of said forward ends receiving and engaging said opposite end portion of one of said pins,

a wire for each of said first contacts, each of said wires being received in and crimped to said rearward end of the contact therefor,

retainer means removably holding said first contacts in said openings,

said retainer means being releasable for allowing said contacts to be removed rearwardly from said openings,

a second dielectric member,

said second dielectric member having a plurality of openings therethrough,

a second socket contact in each of said openings in said second dielectric member,

each of said second contacts having a forward end and a rearward end,

said forward ends of said second contacts being adapted to receive said one end portions of said pins for forming an electrical connection therewith,

a second wire for each of said second contacts,

each of said second wires being received in and crimped to said rearward end of the second contact therefor,

and second retainer means removably holding said second socket contacts in said openings in said second dielectric member.

3. A device as recited in claim 2 including in addition a second member of resilient material interposed between said rearward side of said glass insert and said dielectric insert, said second member of resilient material having openings therethrough, said opposite end portions of said pins extending through said openings in said second member of resilient material.