Multi-contact Electrical Connector

Abstract

Multi-contact Connector Assembly comprises plug and receptacle which contain matable contact terminals. Both plug and receptacle comprise a molded plastic shell member and a molded insert having contact cavities therein, terminals being contained in the insert cavities.

Description

A commonly used type of multi-contact electrical connector comprises a metallic shell member having a plastic insert removably mounted therein. The insert has contact cavities extending therethrough and suitable contact terminals are removably mounted in the cavities. A variety of contact arrangements can be obtained by providing different cavity locations in the inserts for a given shell member. Connectors of this general type are also usually provided with screws or latches for holding the two parts of the connector in engagement with each other after they have been mated.

Connectors of the type described above are generally regarded as being of relatively high quality and are comparatively high priced because of the fact that the shells are machined or die cast parts and auxiliary hardware, such as the latching means and retaining means for holding the insert in the shell, must be provided. These types of connectors are ordinarily used in critical or semi-critical applications where a high degree of reliability is required and where expense is a secondary consideration.

There is, however, a need for a multi-contact connector which has the features of interchangeable contact receiving inserts and latching means and which can be produced at a substantially lower cost than the presently available connectors of the type having metallic shells and auxiliary metallic hardware. There are many circumstances where the physical durability and strength of a metallic shell member are not essential and where an all plastic connector assembly would suffice.

It is accordingly an object of the invention to provide an improved multi-contact electrical connector. A further object is to provide an all plastic connector comprising a plastic shell and a plastic insert in which the contact cavities and terminals are contained. A still further object is to provide a connector shape which conforms to existing standard connector shapes and which is produced entirely of plastic parts.

These and other objects of the invention are achieved in a preferred embodiment thereof which is briefly described in the foregoing abstract, which is described in detail below, and which is shown in the accompanying drawings in which:

FIG. 1 is a perspective view of a connector assembly in accordance with the invention, one of the connector parts being mounted in a panel.

FIG. 2 is a perspective view showing the two parts of a connector assembly in accordance with the invention disengaged from each other.

FIG. 3 is a sectional side view taken along the lines 3--3 of FIG. 2 of the plug portion of the connector assembly.

FIG. 4 is a view similar to FIG. 3 but showing the insert exploded from the connector shell.

FIG. 5 and 6 are views taken along the lines 5--5 and 6--6 of FIGS. 4 and 5 respectively.

Referring first to FIGS. 1 and 2, a preferred form of connector assembly in accordance with the invention comprises a connector plug 2 and a connector receptacle 4. The plug 2 is composed of a generally rectangular shell or housing having a passageway extending therethrough from its rearward end 15 go its forward or mating end 16. The shell may be molded from any suitable plastic material such as nylon and has a relatively thick walled rearward section 6 and a thinner walled forward section 8. An integral collar 10 extends from the external surface of the shell intermediate the ends thereof and screw holes 12 are provided in this collar so that the plug can be mounted on a panel or bulkhead. Additionally, rectangular openings 14 are provided in the collar on opposite sides of the shell for cooperation with latching arms 52 on the receptacle part 4 as will be described below.

Four bosses or ribs 18 are provided on the internal surfaces of the plug shell portion in the corners thereof and extend rearwardly from the mating end 16 towards the rearward end 15. These bosses define rearwardly facing shoulders 20 which are spaced inwardly from the mating face 16 by a substantial distance as shown. Retaining lances 22 are formed integrally with the opposed sidewalls 21 of the shell portion 6 and extend forwardly towards the mating end 16, the ends of these lances being spaced from the rearwardly facing shoulder 20. It should also be noted that shallow recesses 24 are provided in the sidewalls 21 beneath each of the lances 22 so that the lances can be flexed inwardly until their surfaces are almost co-planar with the sidewalls 21. These recesses extend forwardly to the forward or mating end of the shell for the reason that they are formed by core pins when the shell is molded, which extend inwardly from the mating end.

The insert 26 which is adapted to be mounted in the shell has a generally rectangular cross section and may have beveled edges as shown. Laterally projecting ribs 30 extend transversely across two of its opposite sides 31 and define forwardly and rearwardly facing shoulders 32, 34 which cooperate with the lances and shoulders in the shear member to retain the insert in the shell. The insert has a plurality of contact receiving cavities extending therethrough from its rearward side 33 to its mating side 35 and suitable contact terminals which are crimped to the ends of wires 29 are contained in these cavities. The terminals mounted in the insert 26 are recessed inwardly from the mating side 35 of the insert and are adapted to receive projecting terminals 28 which are contained in the receptacle part 4. It will be understood that inserts can be provided for any desired type or size of terminal so that a wide variety of electrical terminals can be mounted in one connector assembly.

The insert 26 may be molded of a suitable plastic, preferably a relatively firm plastic such as dyallyl phthalate. The insert 26 is assembled to the shell by merely aligning it with the hollow interior of the shell as shown in FIG. 4 and moving the insert through the shell until the shoulders 32 lodge against the shoulders 20 and the lances 22 lodge against the shoulders 34. It should be noted that the insert has a relatively close fit within the shell member and very little movement of the insert is permitted relative to the shell so that the terminals in the insert 26 will be engaged with the terminals in the complementary insert in plug member 4 when the connector parts are engaged with each other.

It is common to provide a shield over the emergent wires 29 at the rearward end of the connector and to provide means to clamp wires to the shield so that when an axial pull is applied to the wires, the terminals will not be stressed. In the disclosed embodiment, a two part rectangular shield is provided comprising a channel-shaped lower section 36 which has a forward end 38 fitted over the lower portion of the thick walled part of the shell 6. This lower section of the shield may be ultrasonically bonded or cemented to the shell to secure it permanently in place. The upper channel-shaped hood section 40 complements the lower section 36 and the two parts have interfitting groove and rail means 37 to hold them together when the upper part is mounted on the connector. Additionally, the upper part may have an integral hook 42 on its upper surface which is adapted to snap into a recess 44 on the upper surface of the shell portion 6. The conductors 29 are clamped to the lower shell section 36 by means of a U-shaped bracket 46, the legs of which extend through openings in the shield and a clamping plate 50 which is disposed between the legs of the bracket and which is clamped against the conductors by nuts 48.

The receptacle part 4 of the connector assembly is similar and complementary to the plug part 2 and need not be described in complete detail. Accordingly, the receptacle part is identified by reference numerals which correspond to the reference numerals employed to describe the plug but differentiated by prime marks. The insert mounted in the shell of the receptacle is retained by lances and shoulders as described above with reference to the plug 2. It should be noted that the insert 26 is disposed in the plug part 2 with its mating face 35 co-planar with the forward end of the receptacle and the contacts in the shell do not extend beyond the mating end 16 of the plug The insert contained in the receptacle 4 is recessed from the mating side 16 of the receptacle shell and the contact terminals 28 extend beyond the face of the insert. These contact terminals thus enter the cavities in the plug insert when the parts are mated and are engaged with the contact terminals in the plug. The bosses in the receptacle corresponding to the bosses 18 are, of course, recessed from the mating end of the receptacle. The forward portion 8' of the shell of the receptacle is relatively thick walled and is dimensioned such that it is adapted to receive the forward portion 8 of the plug shell as it is apparent from FIG. 1. Finally, forwardly directed arms 52 are provided on the collar 10' for cooperation with the openings 14 in the collar 10. These arms which are molded integrally with the collar 10, are flexed inwardly when the parts are engaged and function to hold the two parts of the connector in engagement with each other. Axially extending ribs 54 and grooves 56 may be provided on the external surfaces of the plug and receptacle to ensure proper orientation when the parts are engaged with each other.

Either of the connector parts can be mounted on a panel, the receptacle 4 being panel mounted in FIG. 1. It should be noted that a shield for the conductors 29' is not provided on the receptacle 4. This is common practice since the conductors 29 are not ordinarily subjected to handling when the parts are engaged or disengaged as are the conductors 29 extending from the plug 2. A shield can, however, be provided on the receptacle 4 if the plug 2 is panel mounted.

An important feature of the invention is the provision of the forwardly directed lances 22 and the recesses 24 in the sidewalls 21 of the shell members. This arrangement permits the lances to be flexed inwardly until their surfaces are almost co-planar with the sidewall surfaces so that an extremely tight fitting insert can be mounted in either of the connector parts. Furthermore, the inclination of the lances is such that they are stressed in shear if an attempt is made to remove the insert from the shell by imposing an axial pull on the conductors 29 when the clamp 46 is removed. In other words, the lances 22 in FIG. 3 are nearly co-planar with the surfaces of the sidewalls 21 so that they cannot buckle or flex when an attempt is made to remove the insert by an axial pull as described above. This arrangement provides an extremely strong retention system for the insert.

The inserts can be removed from either of the shells by simply inserting a tool having a pair of narrow spaced-apart blades into the shell in a manner such that the blades depress the latch arms 22 so that the insert can be slid rearwardly.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only.

Claims

1. An electrical connector assembly comprising first and second connector parts which are engageable with, and disengageable from, each other, each of said parts comprising: a connector shell and a connector insert, said shell and said insert having rectangular cross-sections, said shell comprising a hollow molding which is open at each end thereof, a plurality of shoulders on the internal surface of said shell facing in one direction, a pair of lances on the internal surface of said shell, said lances being directed in the direction opposite to said one direction, said connector insert being disposed in said shell and having an integral collar extending thereabout intermediate its ends, one side of said collar being against said shoulders, and said lances being against the other side of said collar, and a two part conductor shield on one of said connector parts, said shield extending from the rearward end of said one connector part, one part of said shield comprising a channel section fitted over, and bonded to, said one connector part, and the other part of said shield being removably secured to said one connector part and to said one part of said shield.