GB1577850A

GB1577850A - Electrical connectors

Info

Publication number: GB1577850A
Application number: GB35727/77A
Authority: GB
Original assignee: Ferranti PLC
Current assignee: Ferranti International PLC
Priority date: 1977-08-25
Filing date: 1977-08-25
Publication date: 1980-10-29
Also published as: IT7850458A0; JPS5443591A; FR2406320A1; DE2833624A1; IT1107452B

Description

(54) IMPROVEMENTS RELATING TO ELECTRICAL CONNECTORS (71) We, FERRANTI LIMITED, a Company registered under the Laws of Great Britain, of Hollinwood in the County of Lancaster, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to electrical connectors and particularly, though not exclusively, to connectors for use in hostile environments.

.Many types of electrical connector are known, consisting in the main of two body portions each carrying contact members which are able to mate one with another when the two body portions are placed together.

There are problems with connectors of this type, particularly when they are intended for use in hostile environments, such as underwater. In this sort of situation care has to be taken to keep water away from live contacts, and the connector must be capable of withstanding considerable pressure if it is to be used at any great depth. To overcome these problems, several types of so-called "pressure balanced" connector have been produced.

It is an object of the invention to provide an electric connector which may be readily adapted to operate as a pressure-balanced connector for use in hostile environments.

According to the present invention there is provided an electrical connector which includes two body portions, at least one fixed contact member carried by each body portion, at least one movable probe member mounted in one of the body portions, an electrically-conducting bridge member carried by the probe member, and means operable to move the probe member from said one body portion into the other body portion so that, in operation, the bridge member effects an electrical connection between the two fixed contact members.

The other body portion of the connector may carry a movable shield member arranged to shield the fixed contact in that body portion when the two body portions are separate.

The connector may be arranged such that each body portion includes a plurality of fixed contact members, and each carries an equal number of probe members and shield members, all of the probe members being movable simultaneously by the actuating means.

Each body portion may contain an electrically-insulating viscous medium, and each probe member and shield member may carry seals operable to prevent the ingress of foreign matter into the body portions of the connector.

The invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a sectioned side view of a first embodiment; Figure 2 shows a fixed contact member; Figure 3 shows a probe member; Figure 4 illustrates the operation of the connector of Figure 1; Figures 5 and 6 are sectioned side views of a second embodiment; Figure 7 illustrates another feature of the connector; Figures 8 and 9 illustrate a further embodiment; Figure 10 shows an alternative probe member; and Figures 11 and 12 illustrate the use of the probe member of Figure 10.

Referring now to Figure 1,this shows the two body portions 10 and 11 of a connector.

Each body portion carries a fixed contact member 12, in the form of a tube of electrically conducting material. The fixed contact members have terminal posts 13 to which a conductor may be attached. The fixed contact member 12 in one body portion 11 contains a cylindrical probe member 14 of electrically insulating material. The probe member 14 carries a conducting bridge member 15 near to one end, and the bridge member makes electrical contact with the contact member. A toothed rack 16 is cut into the probe member, and engages a rotatable pinion or quadrant 17 carried by the body portion 11. Each body portion is surrounded by a cover 18, the cover on the two portions being arranged to overlap at the ends.

Figure 2 shows a fixed contact member 12 in greater detail. As already stated, this is a tubular member of conducting material formed with a terminal post 13 at one end and having the other end formed into a number of contact fingers 19. These contact fingers may be plated with gold or a similar contact material. The contact member 13 shown in Figure 2 has a cut-away portion into which the pinion 17 fits; the contact member carried by body portion 10 does not require this feature.

Figure 3 shows a probe member 14. This is a rod of insulating material which carries a dumbbell-shaped bridge member 15. The bridge member presents two contact surfaces 20 which are joined inside the rod by a linking part of the bridge member. The toothed rack 16 is cut in a part of the probe member adjacent to that carrying the bridge member 15.

Figure 4 shows the connector in use. The two body portions have been placed together with the covers 18 interlocking and the fixed contact members in alignment. The pinion 17 has been rotated in an anti-clockwise direction, which has caused the probe member to move out of the body portion 11 and into the fixed contact member of body portion 10. The extent of the movement of the probe member is such that one contact surface 20 of the bridge member 15 is in contact with the fixed contact member in body portion 10, whilst the other contact surface of the bridge member is in contact with the fixed contact member in the body portion 11, thus effecting the required electrical connection between the two parts of the connector.

Although in the connector described above, the fixed contact in body portion 11 is shielded when the probe member 14 is retracted, the contact member in the other body member 10 is exposed. It is possible to provide a shield member of electrically insulating material, of the same shape and cross-section as probe member 14, carried by the body member 10. This shield member may be biased, say by a spring, to occupy a position in which it shields the fixed contact when the two parts of the connector are separated. When the connector is in use, movement of the probe member 14 by pinion 17 causes the shield member to retract and allow the bridge member 15 to make contact as described.

The form of connector so far described has provided only a single contact path. It is a simple matter to provide each body portion of the connector with a plurality of fixed contact members, and to locate a separate probe member in each fixed contact member in one of the two body portions. The actuating means may then be arranged to move all the probe members simultaneously. The shield members may or may not be provided, as is felt necessary.

Using the rack-and-pinion actuating means already described, it will be apparent that all probe members in one body portion must be located on the same side of the pinion, so that all are moved in the same direction. This arrangement is wasteful of space, and may be avoided if each body portion carries equal numbers of probe members and shield members.

Figures 5 and 6 illustrates such an arrangement.

Referring now to Figure 5, this shows the two separate parts of the connector. Each body portion carries an equal number of probe members 14 and shield members 21. The shield members are shorter than the probe members, but also have a rack formed in them to engage.

the pinion 17. When the connector is not in use, as shown in Figure 5, the probe members 14 and shield members 21 extend up to the end face of the body portion so that all conducting contact surfaces are concealed. To ensure correct registration the two body portions may be provided with one or more co-operating pegs 22 and recesses 23.

When the connector is in use, the two body portions are placed together and, preferably, secured to one another. Rotation of the pinion 17 in body portion 11 in the direction of the arrow in Figure 6 will move the associated probe member 14 to the left, and will also move the shield member 21 to the right by the same amount. The probe member pushes the shield member 21 in the other body portion 10 to the left, thus rotating pinion 17 in that body portion and extending the corresponding probe portion 11. Thus it is not necessary to rotate both pinions from outside the connector.

It will be seen that, if the two body portions are secured together, the rotation of one of the pinions 17 performs a switching action, that is the electrical connection between the two parts of the connector may be made and broken without separating the two parts of the connector.

Figure 7 illustrates a possible way of achieving this result. One part of the connector carries two levers 30 and 31, each shaped to fit partway around theother part of the connector when engaged. The inner lever 30 pivots about the axis of the pinion 17 in that part of the connector, but does not rotate the pinion. The lever has a pair of slots 32 each of which engages a corresponding locking pin 33 on the other part of the connector. Figure 7 shows this lever 30 in the position in which the two parts of the connector are secured together. The other lever 31 is arranged to rotate the pinion 17 as it is moved, thus effecting the necessary switching action. Many other ways of doing this are possible.

When a connector is to be used in a hostile environment such as under water, it is necessary to ensure if possible that water and other unwanted material cannot enter the body of the connector. It is also an advantage if the connector may be pressure balanced. In the connector so far described the first requirement may be satisfied by fitting seals in appropriate places. Apart from the usual cable seals, it is possible to fit D-ring seals around the probe and shield members, or mould circumferential lips to act as seals. The second requirement may be met by filling the body of the connector with an electrically-insulating viscous medium such as a suitable grease or jelly. It will be seen that the connector shown in Figures 5 and 6 is such that the volume inside each body portion remains constant, since as a probe member moves out of the body portion, a shield member of the same cross-sectional area moves into the body member by the same amount.

Hence the volume does not change, though, of course, the grease will be moved about.

In the case of the connector described above where all the probe members are carried by one body portion and all the shield members by the other, different arrangements must be made to compensate for changes in the volume inside the two parts of the connector. Figures 8 and 9 illustrate one such arrangement, only one probe member and shield member being shown for simplicity. Parts which are the same as those already illustrated carry the same references.

The main difference between the connector of Figures 8 and 9 and that previously described is the provision of a central piston in each part of the connector. The body portion 10, which carries all the shield members 21, is provided with a hollow piston 40 to which is attached a tension spring 41. As shown in Figure 8 this spring normally holds the piston so that its crown is flush with the end of that body portion. In a similar manner the other body portion 11 , which carries all the probe members 14, is provided with a hollow piston 42, to which is attached a compression spring 43. This piston is also normally positioned with its crown flush with the end of that body portion. In this embodiment the actuator means are of different form, being provided by a rotatable nut 44 having a thread formed in its inner surface to engage with the rack 16 in each probe member. Rotation of the nut 44 thus moves the probe members in the appropriate direction.

As previously described the two parts of the connector are fastened together by some suitable means. As the nut 44 is rotated the probe members 14 move into the other part of the connector, pushing back the corresponding shield members 21. These shield members displace the grease in the body portion 10, and this pushes the piston 40 against the effect of the tension spring 41. Movement of piston 40 pushes piston 42 into the other body portion 11 against the compression spring 43, and movement of this piston 42 displaces the grease inside the body portion 11 to fill the space left by the movement of the probe members. The dimensions of the two pistons must be such as to compensate exactly for the displacement of the probe and shield members.

In all the embodiments so far described which use both probe and shield members, these members have been separate, usually with the probe member being moved by the actuator means. It is possible to combine the probe and shield members into one, as will be described below.

Figure 10 shows one such member. One end 50 carries the bridge member 15 in what is otherwise a moulding of electrically insulating material. The portion between the two ends has the rack 16 formed on one side, and is notched on the other side as shown at 51 to give the member the necessary flexibility. The member shown also carries four 0-ring seals 52, such as are necessary in several of the embodiments described above. The end 50 of the member forms the probe member, whilst the other end forms the shield member.

Figure 11 illustrates the use of the combined member where the actuator means is a pinion 17. The body portion 10, fixed contact members 12 and pinion 17 are provided as in the embodiment of Figures 5 and 6. The combined probe and shield member occupies a pair of fixed contact members 12 and is bent around the pinion 17, with the rack 16 on the inside of the member.

Figure 12 shows the use of the combined member in the case where the actuator means is the threaded nut 44 as shown in Figures 8 and 9. As in the embodiment of Figure 11, the combined probe and shield member occupies two fixed contact members and is bent around between these. The rack, in this case on the outside of the combined member, engages the thread in nut 44.

In either of these two arrangements, operation of the actuator means advances the probe member and retracts the shield member simultaneously.

Other variations in the arrangement will also be possible.

WHAT WE CLAIM IS: 1. An electrical connector which includes two body portions, at least one fixed contact member carried by each body portion, at least one movable probe member mounted in one of the body portions, an electrically-conducting bridge member carried by the probe member, and means operable to move the probe member from said one body portion into the other body portion so that, in operation, the bridge member effects an electrical connection between the two fixed contact members.

2. A connector as claimed in claim 1 in which the said other body portion contains a movable shield member arranged to shield the fixed contact in that body portion when the two body portions are separate.

3. A connector as claimed in claim 2 in

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. unwanted material cannot enter the body of the connector. It is also an advantage if the connector may be pressure balanced. In the connector so far described the first requirement may be satisfied by fitting seals in appropriate places. Apart from the usual cable seals, it is possible to fit D-ring seals around the probe and shield members, or mould circumferential lips to act as seals. The second requirement may be met by filling the body of the connector with an electrically-insulating viscous medium such as a suitable grease or jelly. It will be seen that the connector shown in Figures 5 and 6 is such that the volume inside each body portion remains constant, since as a probe member moves out of the body portion, a shield member of the same cross-sectional area moves into the body member by the same amount. Hence the volume does not change, though, of course, the grease will be moved about. In the case of the connector described above where all the probe members are carried by one body portion and all the shield members by the other, different arrangements must be made to compensate for changes in the volume inside the two parts of the connector. Figures 8 and 9 illustrate one such arrangement, only one probe member and shield member being shown for simplicity. Parts which are the same as those already illustrated carry the same references. The main difference between the connector of Figures 8 and 9 and that previously described is the provision of a central piston in each part of the connector. The body portion 10, which carries all the shield members 21, is provided with a hollow piston 40 to which is attached a tension spring 41. As shown in Figure 8 this spring normally holds the piston so that its crown is flush with the end of that body portion. In a similar manner the other body portion 11 , which carries all the probe members 14, is provided with a hollow piston 42, to which is attached a compression spring 43. This piston is also normally positioned with its crown flush with the end of that body portion. In this embodiment the actuator means are of different form, being provided by a rotatable nut 44 having a thread formed in its inner surface to engage with the rack 16 in each probe member. Rotation of the nut 44 thus moves the probe members in the appropriate direction. As previously described the two parts of the connector are fastened together by some suitable means. As the nut 44 is rotated the probe members 14 move into the other part of the connector, pushing back the corresponding shield members 21. These shield members displace the grease in the body portion 10, and this pushes the piston 40 against the effect of the tension spring 41. Movement of piston 40 pushes piston 42 into the other body portion 11 against the compression spring 43, and movement of this piston 42 displaces the grease inside the body portion 11 to fill the space left by the movement of the probe members. The dimensions of the two pistons must be such as to compensate exactly for the displacement of the probe and shield members. In all the embodiments so far described which use both probe and shield members, these members have been separate, usually with the probe member being moved by the actuator means. It is possible to combine the probe and shield members into one, as will be described below. Figure 10 shows one such member. One end 50 carries the bridge member 15 in what is otherwise a moulding of electrically insulating material. The portion between the two ends has the rack 16 formed on one side, and is notched on the other side as shown at 51 to give the member the necessary flexibility. The member shown also carries four 0-ring seals 52, such as are necessary in several of the embodiments described above. The end 50 of the member forms the probe member, whilst the other end forms the shield member. Figure 11 illustrates the use of the combined member where the actuator means is a pinion 17. The body portion 10, fixed contact members 12 and pinion 17 are provided as in the embodiment of Figures 5 and 6. The combined probe and shield member occupies a pair of fixed contact members 12 and is bent around the pinion 17, with the rack 16 on the inside of the member. Figure 12 shows the use of the combined member in the case where the actuator means is the threaded nut 44 as shown in Figures 8 and 9. As in the embodiment of Figure 11, the combined probe and shield member occupies two fixed contact members and is bent around between these. The rack, in this case on the outside of the combined member, engages the thread in nut 44. In either of these two arrangements, operation of the actuator means advances the probe member and retracts the shield member simultaneously. Other variations in the arrangement will also be possible. WHAT WE CLAIM IS:

1. An electrical connector which includes two body portions, at least one fixed contact member carried by each body portion, at least one movable probe member mounted in one of the body portions, an electrically-conducting bridge member carried by the probe member, and means operable to move the probe member from said one body portion into the other body portion so that, in operation, the bridge member effects an electrical connection between the two fixed contact members.

3. A connector as claimed in claim 2 in

which each body portion carries a plurality of fixed contact members, one body portion having a like plurality of probe members and the other body portion having a like plurality of shield members.

4. A connector as claimed in claim 2 in which each body portion carries a plurality of fixed contact members, the two body portions each carrying equal numbers of probe members and shield members.

5. A connector as claimed in any one of claims 1 to 4 in which each probe member is formed with a toothed rack, and which includes a rotatable pinion in engagement with the rack on each probe member, such that rotation of the pinion causes linear movement of the probe member.

6. A connector as claimed in claim 5 which includes a lever located outside the body portion and movable to cause rotation of the pinion.

7. A connector as claimed in any one of claims 1 to 4 in which each probe member is formed with a toothed rack, and in which at least one body member includes a rotatable nut in engagement with the rack on each probe member, such that rotation of the nut causes linear movement of the probe member.

8. A connector as claimed in any one of the preceding claims in which each body portion contains an electrically-insulating viscous medium.

9. A connector as claimed in claim 8 in which each body portion includes means for compensating for changes in the volume of the body portion due to movement of the probe members.

10. A connector as claimed in claim 9 in which the means comprise a spring-loaded piston.

11. A connector as claimed in claim 4 in which each probe member is formed integrally with a shield member.

12. A connector as claimed in any one of the preceding claims which includes means for securing the two body portions together prior to the extension of the probe members.

13. A electric connector substantially as herein described with reference to the accompanying drawing.