Underwater Electrical Connector

Abstract

An underwater electrical connector for providing cable strain relief in order to eliminate the possibility of wire breakage at the terminal area. Redundant safety is provided by means of a primary header and a secondary header, each of which has glass sealed contacts mounted therein. Moreover, a cable strain relief is formed by means of a wave washer on the terminal assembly. When the cable flexes, the wave washer is compressed, allowing axial movement of the entire assembly surrounded by a sleeve and relieving the strain on individual terminal joints formed between the wires of the cable and socket contacts of the connector. The device could be used where the cable is subjected to vibration and oscillation due to movement, resulting in substantial possibility of wire breakage at the terminal area.

Description

The invention relates in general to underwater electrical connectors and, more particularly, to a connector having a cable strain relief for eliminating the possibility of wire breakage at the terminal area.

BACKGROUND OF THE INVENTION

A major problem in underwater electrical connectors is the sufficient fastening of a stranded wire to a rigid contact member. It has been found that most failures in underwater electrical cable systems occur as the result of wire breakage at the attachment point of the connector pin or socket. These failures generally are caused by flexing of the cable near the connector. Conventional crimp joints are less likely to break under flexure than a soldered joint, which stiffens the wire. However, the rigid specifications necessary for underwater electrical connectors require that these connectors must withstand hydrostatic pressures up to 10,000 lbs. Thus, compression-glass sealing must be utilized to withstand the high pressures per square inch in both the mated and unmated condition, but compression glass sealed headers cannot contain crimp contacts. Thus, despite the fact that solder joints crack or break after five or six flexings it has been found necessary to utilize solder joints on a glass sealed receptacle connector.

In order to overcome the attendant disadvantages of prior art underwater electrical connectors, the present invention incorporates a secondary glass sealed header within the primary header for redundant safety, together with a cable strain relief to preclude the possibility of wire breakage and simultaneously allowing crimp snap-in contacts on the terminal side of the receptacle connector. Thus, should the cable be subjected to vibration and oscillation due to movement, the possibility of wire breakage at the terminal area is substantially reduced.

The advantages of this invention, both as to its construction and mode of operation will be readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

The FIG. depicts a preferred embodiment of the underwater electrical connector, partly in section.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, there is shown a hydrospace connector assembly comprising a plug connector 12 which is normally mated to a receptacle connector 14 external portions of which are subjected to fluid pressures and oscillation. The receptacle connector 14 protrudes through a bulkhead 16 which may be a ship wall or other underwater member. The bulkhead 16 contains an enlarged forward diameter bore 18 and a reduced rear diameter bore 22. The junction of the two bores define a forward facing shoulder 24 in the bulkhead. Further, the bulkhead contains a forward facing wall 26 which may be exposed to the exterior or high pressure of the ship or other member, and an interior wall 28 which would normally be exposed to the inner portion of the vehicle or structure. However, both walls 26 and 28 may be exposed to fluid pressure dependent on the application. In normal configuration, wall 26 is exposed to higher pressures.

The receptacle connector 14 comprises a primary header 32 which acts as a penetrating body extending into the interior of the vehicle or other member. The primary header 32 comprises a forward extending section 34 which is threaded at its forward end on its exterior surface 36. The header further comprises an outwardly extending flange 38 whose rear surface 42 forms a shoulder which abuts the forward wall 26 of the bulkhead. A groove 44 along the surface 42 allows an O-ring 46 to be inserted providing a sealed surface between the front surface 26 and the surface 42. The primary header 32 further comprises a main body section 52 whose outer surface 54 is slightly less than the diameter of opening 18 in the bulkhead, and is secured therein. Further, a rearward facing shoulder 56 of the body 52 abuts the forward facing shoulder 24 of the bulkhead and a groove 58 in the shoulder 56 contains an O-ring 62 to provide a sealing surface between surfaces 24 and 56. Further, a tubular section 64 of the primary header 32 extends from the main section 52 and is secured within the reduced diameter section 22 of the bulkhead 16. The section 64 terminates short of the interior wall 28 and contains a rearward facing surface 66 and internal threads 68 which extend from the rearward facing surface 66 short of the rearward facing shoulder 56 of the header. An inner surface 72 of tubular section 64 extends somewhat past the rearward facing shoulder 56. The primary header further comprises a forward facing surface 76 which defines the front portion of the primary header between the threaded surface 36 and an inner surface 78 of section 34. The inner surface 78 extends from the forward surface 76 back to a forward facing shoulder 79 which defines the rear end of opening 78. A groove 80 is formed along the surface 78 towards the forward surface 76. Further, a polarizing key 81 is secured to the surface 78. A reduced diameter bore 84 penetrates the primary header from the shoulder 79 to a rearward facing shoulder 86. An intermediate bore 88 in the header 32 terminates at the rearward facing shoulder 86 at one end and at the other end, at a rearward facing shoulder 92. The shoulder 92 interconnects surface 72 with the bore 88.

The receptacle connector 14 further comprises a header retaining sleeve 102 having a forward section 104 whose outer surface contains threads 106 which mate with the threads 68 of the primary header 32 and an enlarged rear section 108 whose rear end portion 112 is threaded at its outer surface 114. A forward facing shoulder 116 is formed between the forward section 104 and the enlarged rear section 108. The shoulder 116 is spaced from the surface 66 of the primary header 32, and contained in the spacing is an O-ring 118. The rear end of the section 112 is defined by a rearward facing end face 122. Mounted within the header retaining sleeve 102 is a sleeve 124 whose outer diameter is slightly less than the inner diameter of the retaining sleeve 102. The forward end of the sleeve 124 contains a forward facing shoulder 126. The inner surface of the sleeve 124 contains an enlarged forward bore 128 and a reduced diameter rear bore 132, with a forward facing shoulder 133 intermediate the bores 132 and 128. An annular groove 134 is formed in the forward bore 128 just to the rear of the shoulder 126. The sleeve 124 further contains an outwardly extending flange 136 and a groove 138 along its outer periphery. Further, the rear end of the sleeve 124 contains threads 142 along its periphery and terminates in a rear end face 144.

A retaining nut 152 contains internal threads 154 and a forward face 156 and a rear face 158. The retaining nut's threads 154 are threaded to the forward portion of the threaded outer surface 114 of the retaining sleeve 102 and the forward face 156 abuts the interior wall 28 of the bulkhead.

A resilient coupling nut 162 is threaded at its forward inner portion 164, the threads mating with the rear part of the threaded outer surface 114. A forward facing wall 166 of the coupling nut abuts the rear facing face 158 of the retaining nut 152. The rear end of the coupling nut 162 contains an inwardly extending flange 168 whose inner surface abuts the outer surface of the sleeve 124 just forward of the annular groove 138. A forward surface 172 of the flange 168 is spaced from the rear surface of the flange 136 forming an opening therebetween. The rear surface 174 of the flange abuts the forward facing surface of a retaining ring 176, which is mounted in the annular groove 138. A wave washer 178 is mounted in the opening between the rear surface of the flange 136 and the forward facing surface 172, and is movable in an axial direction therein.

A cable clamp 182 is formed of a sleeve 184 whose front end 186 is threaded at the interior 188 thereof, and mates with the threads 144 of the sleeve 124. Further, a strap 192 extends perpendicular to the axis of the connector and is secured to the sleeve 184 by means of screws 194.

The cable 10 is secured to the cable clamp 182 by means of strap 192 and screws 194. Thus, any axial movement of the cable to the rear of the connector assembly will be transmitted to the cable clamp and thereby absorbed by the wave washer 178. A portion of the cable within the sleeve -24 has its outer jacketing removed, exposing the insulated wires 202 of the cable.

The forward end of the reduced diameter rear bore 132 of the sleeve 124 has mounted therein, an insulator assembly made up of a grommet 204, and diallyl insulators 206, 208 mounted within the enlarged forward bore 128 with the rear surface of insulator 208 abutting shoulder 133 of sleeve 124. The wires 202 are crimped to socket contacts 212 and are inserted through grommet 204. A rear release contact retention assembly 214 is retained in the insulator 208. The socket contact 212 is retained in an opening 218 in insulator 206 by virtue of retention assembly 214. The contact 212 contains a shoulder 222 to insure positive retention. The contact 212 is secured to the wire 202 to form a conductive path for the wire 202 through the connector. Mounted in the inner surface 72 of the primary header 32 is a secondary header 232 normally made of stainless steel, and having an annular groove 234 along its outer periphery into which an O-ring 236 forms a seal with the primary header 32. A hole 238 drilled in the secondary header 232 contains a conductive pin 242 which has been sealed within the secondary header 232 by means of compression glass 244. The rear face of the secondary header abuts the front face of the insulator 206, and the pin 242 is inserted into the contact 212. The intermediate bore 88 in the primary header 32 contains a pair of diallyl insulators 246, 248. The diallyl insulator 246 contains a reduced diameter forward bore portion 252 interconnected to a rear diameter enlarged bore 254 and the insulator 248 contains an enlarged forward bore 256 and reduced rear bore 258. Mounted within the bores 254, 256 is a double ended socket contact 262. Pin contact 242 extends through reduced diameter 258 into one end of socket contact 262.

The opening 84 in the primary header 32 contains a hermetically sealed conductive pin 272 which is sealed in compression glass 284. The rear end of the pin 272 extends into the bore 252 of insulator 246 where it contacts the socket 262. The front end of the pin 272 protrudes through an interfacial seal 286 which abuts the forward facing shoulder 79 of the primary header 32.

The plug 12 is formed of a body 302 whose rear end 304 contains an opening 306 which tapers outwardly. Adjacent the opening 306 along the inner surface 308 of the sleeve is an annular groove 310. The sleeve contains an outwardly extending flange 312 having a reduced forward portion 314. The front end of the sleeve 302 contains a reduced outer diameter portion 316. Adjacent the outer diameter 316 there is an O-ring 318 mounted in the annular groove 80 of the header 32. Further, an O-ring 320 is mounted between the forward facing surface 76 of the header and the front surface of flange 312 and the top surface of portion 314. A keyway 322 is formed at the forward end of the body 302 for mating with the polarizing key 81. Further, the forward end of the body 302 contains an inwardly extending flange 324 whose front surface mates with the interfacial seal 286. A plug coupling ring 332 is threaded at its forward inner section 334 so as to mate with the threads on the exterior surface 36 of the primary header 32. Further, the rear end of the ring 332 contains an inwardly extending flange 336 whose forward surface mates with the rear surface of flange 312 and whose rear surface abuts a nylon friction washer 338 mounted on the outer surface of the plug sleeve 302. Mounted within the plug sleeve is an insulator retaining sleeve 342 that is held within the sleeve by means of a retaining ring 344 mounted in the groove 310 of the plug sleeve 304. The front end of the retaining sleeve 342 abuts a diallyl insulator 346. The insulator is secured to the rear surface of the flange 324 at a tapered reduced outer diameter portion 348. Adjacent the rear surface of the insulator 346 is a diallyl insulator 350 and adjacent the rear surface of the diallyl insulator 350 is a rubber grommet 352. Mounted in the insulator 346 and 350 is a socket contact 354 which is crimped to wire 358 and inserted through grommet 352. The pin 272 which extends through the seal 286 is inserted in socket contact 354 mounted in the insulator 346. The socket contact contains a shoulder portion which abuts the releasable retaining assembly 364.

To relieve strain on the cable 12 in order to eliminate the possibility of the wire 202 breaking at the terminal area, the wave washer 178 is utilized on the terminal assembly. When the cable 12 flexes, the wave washer is compressed, allowing axial movement of the entire assembly surrounded by sleeve 124, and thus relieving the strain on the individual terminal joints formed between the wires 202 and the socket contacts 212. Without the cable strain relief as described, the cable, being subjected to vibration and oscillation, transmits the strain directly to the termination. Further, it should be understood that while the cable clamp is depicted as a straight clamp, a 90.degree. cable clamp, or other conventional cable clamp could be used.

The secondary header 232 which acts as a secondary pressure bulkhead, is sealed within the primary header 32 and retained with the assembly by means of the retaining nut 152 between the forward facing shoulder 126 of the retainer sleeve 102 and the rearward facing shoulder 92 of the secondary header 232. Should the primary header 32 for any reason fail, the pressures will be contained entirely by the secondary header 232, thus providing an additional safety factor for the connector.

The terminal area utilizes crimped contacts for connecting the wires 202 to the receptacle 14. Thus, operator error in soldering is eliminated in the normal soldering steps of cleaning, pretinning, applying the correct heat, correctly stripping the wires and in other problems attendant with solder-type terminations.

While the system has been depicted as using a rear release contact retention assembly located in the insulators 206, 208 and 346 and 350, it should be understood, of course, that the connector assembly will work equally as well with a front release assembly.

It should be further noted that the plug assembly is designed for potting and molding prior to subjecting it to fluid pressures. However, it should be understood that should the plug not be mated to the receptacle, the receptacle alone will withstand fluid pressures.

Further, while the interconnection between the cable 12 and the connector assembly has been depicted for only one wire 202 in the drawing, it should be understood, of course, that the connector assembly could be utilized for a multiwire system utilizing all the wires of the cable 12.

Moreover, while the cable clamp and wave washer assembly have been depicted as being used only on the interior of the bulkhead such as in an intermediate area where fluid may be present, it may, of course, be utilized on the exterior side of the bulkhead as well.

Claims

What I claim is:

1. An underwater electrical connector comprising:

a connector member having contacts for interconnection with a mating connector member;

a connector shell having a wave washer mounted in the shell;

a cable member secured to said connector shell and having wires connected to said contacts;

a cable clamp securing said cable to said connector shell, axial movement of said cable and cable clamp compressing said wave washer and relieving strain on the terminal joint formed between the cable wires and the contacts of said connector;

a retaining sleeve mounted within said connector member, a resilient coupling nut secured to said retaining sleeve and said wave washer disposed adjacent to said resilient coupling nut; and

a resilient sleeve whose outer surface is flush with the inner surface of said retaining sleeve, said resilient coupling nut being threadedly secured to the outer surface of said retaining sleeve, said wave washer being mounted adjacent the outer surface of said resilient sleeve.

2. An underwater electrical connector in accordance with claim 1 wherein said cable clamp is threadably secured to said resilient sleeve and a cable strap secures said cable to said cable clamp.