Plug and receptacle connectors

Abstract

 A coaxial plug connector for use as an insert in a first connector housing comprises a first generally cylindrical outer shell (12), a socket (14) centered on the axis of the shell and a sleeve of electrically insulating material between the socket and the shell. The forward end of the insulating sleeve projects beyond the forward end of the socket and has peripheral regions defining a first male frustoconical or other convex face (20). It is used in combination with a' coaxial receptacle connector for use as an insert in a second connector housing and has a second generally cylindrical outer shell (36) dimensioned to mate with the first outer shell, a contact pin (38) centered on the axis of the second shell and an insulating sleeve (30) whose forward end is recessed behind the forward end of the contact pin and has regions (44, 46) defining complementary frustoconical faces to those at the forward end of the plug connector. In use the convex face of the plug connector assists in eliminating misalignment between the plug and receptacle during mating of the first and second connector housings.

Description

[0001] The present invention relates to coaxial plug and receptacle connectors for electrical cables carrying an alternating electrical current and more particularly with connectors for use with two-part connector housings, one half of which snakes edge connection with a removable printed circuit board and the other half of which is connected to the main frame into which the board is connected. Such connector housings are generally rectangular and may have a number of connector pins received in respective sockets in the mating half for carrying direct or low frequency alternating current and also one or more coaxial plug or receptacle inserts to which a coaxial electrical cable may be connected for carrying higher frequency alternating current. Similarly the invention may be applied to plug and receptacle inserts for multi-way circular connectors.

[0002] A problem associated with previously known two-part connectors is that of accurately aligning the plugs and the receptacles in each half so that they may be pushed smoothly together. An object of the invention is to provide a plug and receptacle for fitting into the parts of the housing which cooperate to bring about progressive alignment as the parts of the connector housing are mated together.

[0003] In one aspect the invention provides a coaxial plug connector comprising a first generally cylindrical outer shell, a socket centered on the axis of the shell, and a sleeve of electrically insulating material between the socket and the shell, the forward end of the insulating sleeve projecting beyond the forward end of the socket and having peripheral regions defining a first male frustoconical or other convex face.

[0004] The invention also provides a coaxial plug and receptacle connector comprising a coaxial plug connector as aforesaid in combination with a socket connector having a second generally cylindrical outer shell dimensioned to mate with the first outer shell, a contact pin centered on the axis of the second shell and an insulating sleeve whose forward end is recessed behind the forward end of the contact pin and has regions defining complementary frustoconical faces to those at the forward end of the plug connector.

[0005] The invention also provides a two-part multi-pin connector comprising a mating male connector housing and female connector housing, each having a plurality of axial bores in which are disposed respective receptacle inserts as defined above and plug inserts as defined above.

[0006] Other preferred aspects of the invention will be found in the appended claims, to which attention is hereby directed.

[0007] An embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which:

Figure 1 shows the forward end of a coaxial plug connector and a coaxial socket connector in maximum misaligned position with bores in respective male and female connector housings;

Figures 2 to 6 show successive stages in the mating of the connectors shown in Figure 1.

[0008] A plug connector generally indicated by the reference numeral 10 has a generally cylindrical metal outer shell 12, a socket 14 centered on the axis of the shell 12 and opening to the forward end thereof, and a cylindrical sleeve 16 of insulating material. The forward end of the insulator sleeve projects beyond the forward end 13 of the socket and -as a male frustoconical cuter periphara face 20 and a female frustoconical inner peripheral face 22. The forward end 24 of the outer conductor 12 terminates behind the end 18 of the socket 14 and is also in the form of a male frustoconical face. In the embodiment shown, the frustoconical face 24 is positioned behind the frustoconical face 20, but the outer conductor 12 may terminate nearer to the forward'end of the plug so that the faces 20 and 24 are continuous. The plug connector 10 floats in a bore 26 in a female connector housing 28 to which it is generally secured by means of a resilient clip (not shown) or other resilient support means.

[0009] A receptacle generally indicated by the reference numeral 30 floats in a bore 32 in a male connector housing 34 to which it is also generally secured by means of a resilient clip (not shown). It comprises a generally cylindrical metal outer shell 36 dimensioned to be a sliding fit over the outer cylindrical wall of the outer shell 12, a central contact pin 38 being centered on the axis of the shell 36 and dimensioned to fit into the socket 14, and a cylindrical sleeve 40 of insulating material being disposed between the pin 38 and the shell 36. The forward end of the insulator sleeve 40 is recessed well behind the forward end 42 of pin 38 and has a female outer peripheral frustoconical face 44 conforming to the forward end 24 of the outer conductor 12, a female intermediate frustoconical face 46 conforming to the male frustoconical face 20 of the insulator sleeve 16. The forward end 50 of the outer shell 36 has a further female frustoconical face.

[0010] Successive stages in the mating of the male and female parts of the connector housing and of a plug and receptacle connector within said housing are shown in Figures 2 to 6. As is apparent from Figure 1, the plug and receptacle inserts 10,30 in the separate connector housings are allowed to float in respective bores 26, 32 positioned so that their axes are aligned when the parts of the connector housing are brought together, but with the floating support for the inserts allowing their axes to be directed at angles 0, and 0₂ of typically up to 4 degrees to the axes of the bores 26 and 32. The first stage of alignment (Figure 2) occurs when the male frustoconical face 20 of the plug insulator sleeve impacts against a female frustoconical face 52 at the forward end of the bore 32 in the male connector housing 34 which begins to align the axis of the plug connector 10 with the axis of the bore 32. In the next stage (Figure 3) the male frustoconical face at the forward end 24 of the outer conductor engages the face 52 which further aligns the plug connector towards the axis of the bore 32. Further movement of the male and female connector housings towards one another brings the frustoconical face 20 into engagement with the end face 50 of the outer shell 36 (Figure 4) which begins to align the axis of the plug connector 10 with that of the receptacle 30. Subsequently the front face 24 of the outer conductor engages the end face 50 substantially to complete the alignment of the axis of the plug connector with that of the receptacle 30 (Figure 5) and the female face 22 acts as a lead-in to guide the pin 42 into the socket 14, after which the male and female connector housings can be slid to the fully mated position (Figure 6).

[0011] The arrangement described above offers advantages over known arrangements in which the plug and the receptacle are aligned by means of their outer shells. In such arrangements the wipe length of the central pin and socket; is reduced and if, as often happens, the male and female connector housings are incorrectly mated and end up at a slight angle, some of the pins and sockets towards one edge of the connector housing may be connected over only a small wipe length or may not even be connected at all. It has also been suggested that the plug and receptacle should be aligned by means of the inner pin, but this requires that the inner pin should have at least a minimum diameter to give the required mechanical strength. In the present arrangement this restriction on the minimum diameter of the inner pin is removed so that inner pins of much smaller diameter can be used and connectors of higher characteristic impedance can be produced. The present arrangement is expected to be of special value for hybrid connectors because it does not have to be manufactured to close tolerances and can accommodate a greater degree of mis-alignment relative to the connector housing than conventional plug and receptacle inserts.

Claims

1. A coaxial plug connector comprising a first generally cylindrical outer shell, a socket centered on the axis of the shell and a sleeve of electrically insulating material between the socket and the shell, characterised in that the forward end of the insulating sleeve projecting beyond the forward end of the socket and having peripheral regions defining a first male frustoconical or other convex face (20).

2. A plug connector according to Claim 1, characterised in that the forward end of the outer shell (12) terminates behind the forward end of the socket (18) in a second male frustoconical face (24).

3. A plug connector according to Claim 1 or 2, characterised in that the forward end of the insulating sleeve (20) has central regions defining a female frustoconical face (22) which forms a lead-in to the socket.

4. A coaxial plug and receptacle connector comprising in combination a coaxial plug connector as claimed in any of Claims 1 to 3 and a receptacle having a second generally cylindrical outer shell dimensioned to mate with the first outer shell, a contact pin centered on the axis of the second shell and an insulating sleeve characterised in that the forward end of the sleeve (30) is recessed behind the forward end of the contact pin (38) and has reaions defining complementary frustoconical faces (44, 46) to those at the forward end of the plug connector.

5. A two-part multi-pin connector comprising a male connector housing and a mating female connector housing each having one or more bores positioned to be in axial alignmenmt when the male and female connector housings are mated together, a coaxial plug connector held hv resalient suport means in one of the bores in said male or female connector housing constituted by a first generally cylindrical outer shell, a socket centered on the axis of the shell and a sleeve of electrically insulating material between the socket and the shell, a mating receptacle held by resilient support means in an axially alignable bore in the other said male or female connector housing and having a second generally cylindrical outer shell dimensioned to mate with the first outer shell, a contact pin centered on the axis of the second shell and an insulating sleeve, characterised in that the insulating sleeve (16) of the coaxial plug connector projects at its forward end (18) beyond the forward end of the socket (14) and has peripheral regions defining a first male frustoconical or other convex guide face (20), the insulating sleeve (40) of the receptacle is recessed behind the forward end of the contact pin (38) and has regions defining a complementary frustoconical face (46) to that at the forward end of the plug connector, the arrangement being such that misalignment between the axes of the coaxial plug (10) and the receptacle (30) and their respective bores (26, 32) is progressively reduced as said male and female connector housings (28, 34) are mated together.

Drawing