Locking connector

Abstract

A locking connector (10) comprises a body (19) which defines apertures each to receive pins which have the same, first, orientation as the pins of a C14 type plug and pins which have the same, second, orientation as the pins of a C20 type plug, the connector comprising a locking mechanism (25) which is displaced by a plug pin upon insertion of the plug thereby to permit insertion of the plug but which seizes the pin on attempted withdrawal of the plug, said locking mechanism comprising a first pair (27) of retention surfaces for engaging with a pin of a first orientation and a second pair (28) of retention surfaces for engaging with a pin of a second orientation.

Description

[0001] Locking Connector

[0002] This invention relates to a connector and more particularly but not exclusively to a connector for use between items of electrical equipment or to connect electrical equipment to a power supply.

[0003] Various proposals have been made and employed to reduce the ease with which plugs may be removed or inadvertently be displaced from sockets in electrical equipment. One long established technique, especially for computer equipment, is to employ screws or clips at either side of the plug to keep the plug attached to the equipment to which it is connected. Screwing or clipping the plug to the equipment, however, is laborious and often a quick visual inspection does not reliably indicate whether or not a screw or clip is engaged with the equipment.

[0004] For many applications it may be desirable to lock individual pieces of equipment together more permanently than many prior art solutions allow. This invention seeks to provide a locking connector that may be operated easily and quickly.

[0005] Commonly used connectors for use in connecting electrical equipment to a power supply are in the form of one of four types of sockets that are in accordance with the International standard IEC 60320. The commonly used types of socket are designated as C14, C16, C20 and C22. The apertured end faces of connectors of these types are shown in Figure 1 .

[0006] The aforementioned four types of socket all comprise a front face which defines three rectangular apertures for receiving respective rectangular earth, neutral and live pins of a plug.

[0007] In the C14 and C16 sockets the rectangular earth pin aperture has, as viewed in cross section, a length direction longer than a width direction of the aperture and which length direction is perpendicular to the direction in which live and neutral apertures are spaced. The outer profiles of the C16 and C14 sockets differ in that, as viewed in cross section, one edge of the body of the C16 socket if formed with a recess region.

[0008] The C20 and C22 sockets differ from the C14 and C16 sockets in that the length direction of each rectangular pin aperture extends in the same direction and said length direction is perpendicular to the length direction of the apertures of the C14 and C16 sockets. The C20 and C22 sockets differ in that, as viewed in cross section, the body of the C20 is of a generally rectangular shape whereas the body of the C22 socket has two chamfered corners.

[0009] In the case of C14 and C16 type sockets it is known that they may be of a type which automatically locks the pins of a plug in position within the socket and permits removal only when a release mechanism is operated. Sockets of that type are described in more detail in the specification of our EP1459512 and provide a simple and convenient means for effectively inhibiting unauthorised or inadvertent separation of a plug from a socket.

[0010] However the mechanism described in EP 14595112 is not readily adaptable to providing lockable versions of C20 and C22 type plugs.

[0011] The present invention seeks to provide a locking connector which comprises a locking mechanism operable in particular, but not exclusively, to securely retain a pin of an inserted plug of a C20 or C22 type to prevent unauthorised or inadvertent removal of the plug.

[0012] The present invention further seeks to provide a locking connector in the form of a socket able to receive and securely lock in position the pins of a plug such as of any of the types normally received by a C14, C16, C20 or C22 socket, and said socket comprising a locking mechanism to securely retain a pin of the inserted plug.

[0013] In accordance with one aspect of the present invention there is provided a locking connector comprising a body which defines apertures each to receive pins which have the same, first, orientation as the pins of a C14 type plug and pins which have the same, second, orientation as the pins of a C20 type plug, the connector comprising a locking mechanism which is displaced by a plug pin upon insertion of the plug thereby to permit insertion of the plug but which seizes the pin on attempted withdrawal of the plug, said locking mechanism comprising a first pair of retention surfaces for engaging with a pin of a first orientation and a second pair of retention surfaces for engaging with a pin of a second orientation.

[0014] The locking mechanism may comprise one movable member which defines the two pairs of retention surfaces. Alternatively the locking mechanism may comprise a first movable member that defines the first pair of retention surfaces and a second movable member that defines the second pair of retention surfaces.

[0015] Preferably the locking member comprises a movable member which is resiliently biased and which may be deflected from a biased position by means of a release mechanism that acts against a biasing means thereby to permit removal of the plug from the connector.

[0016] Each of the apertures of the front face of the body may be of a T shape thereby to receive pins of a plug of the C14 and C16 types and / or to receive pins of a plug of the C20 and C22 types. However a T shape is not essential and other shapes may be employed to receive the pins of a plug.

[0017] For a connector comprising earth, live and neutral terminals the movable member of the locking mechanism preferably is arranged to engage with the earth pin of an inserted plug, thereby to secure the plug relative to the connector.

[0018] The present invention teaches that the locking mechanism may comprise a first pair of oppositely positioned pin retention surfaces and a second pair of oppositely positioned pin retention surfaces, the surfaces of one pair being spaced apart in a direction substantially at right angles to the direction in which the pin retention surfaces of the other pair are spaced apart.

[0019] A single movable member may provide the two pairs of pin retention surfaces. However in an alternative construction, and for example a construction in which the locking mechanism comprises two movable members which each define a pair of pin retention surfaces, the surfaces of one pair may be spaced apart in a direction either substantially at right angles relative to or parallel with the direction in which the pin retention surfaces of the other pair are spaced apart.

[0020] The or each movable member may be in the form of a latch plate, for example a plate of metal or ceramic material.

[0021] If the locking mechanism comprises two latch plates, the first of the two latch plates may define retention surfaces between which a pin of a first type of plug may extend freely, to be captured by the second latch plate positioned behind the first of the two latch plates and the first of the two latch plates may define retention surfaces for engagement by a pin of the second type of plug.

[0022] The or each latch plate may define an aperture within the outer profile of the latch plate or an aperture at a recess region which is defined by the outer profile of the latch plate and comprises at least one pair of the retention surfaces.

[0023] If the locking mechanism comprises two latch plates, each may pivot either about an axis that is perpendicular relative to the direction in which the live and neutral pin apertures are spaced apart or about an axis that is parallel with said direction. Particularly if a latch plate comprises two pairs of pin engagement surfaces, preferably the latch plate is pivotable about an axis that is perpendicular relative to the direction in which the live and neutral apertures are spaced apart. The latch plate may define an aperture of a T shape. The T shaped aperture may define two pairs of pin engagement surfaces. The T shaped aperture preferably is pivotable about an axis parallel with the length of the stem section of the T shape, namely perpendicular to the head section of the T shape.

[0024] A latch plate may define an aperture of other than a T shape. It may, for example, define an aperture of a circular or elliptical shape. The shape and position of contact with a pin may be such as to provide a substantially line type contact or a point type contact with an inserted pin. The latch plate may be employed to provide contact with an edge or a face of an inserted pin.

[0025] The dimensions of the aperture defined by the latch plate preferably are substantially the same as those of a cross section of a portion of the pin. This may mean that, if the plate is substantially perpendicular to the direction of insertion of the pin, the pin may be freely inserted but, when the plate is angled with respect to the direction of elongation of the pin, the plate seizes the pin. Preferably the plate is biased (preferably resiliently) towards an angled position. This may assist the retaining mechanism in operating as soon as forces are applied to the pin to remove it from the connector.

[0026] Preferably a movable member such as a latch plate is angled, in the absence of an inserted pin, to reside inherently at an angle of between 5° and 25°, more preferably between 100and 200degrees relative to a plane that is perpendicular to the direction of insertion of the pin of a plug.

[0027] Preferably at least one edge of the aperture defined by the latch plate engages and retains the pin by frictional forces. This may provide a simple but effective mechanism by which the pin may be retained in the socket.

[0028] Preferably a pair of oppositely positioned pin retention surfaces comprise at the front face of the plate a first angular edge at one side of the aperture and at the rear face of the plate a second edge at the opposite side of the aperture, the first and second edges being arranged to bite into the pin when the plate is angled. The edges are preferably angular, for example substantially square corners. The plate is preferably at least 0.5mm thick, more preferably at least 1 mm thick.

[0029] Preferably the biased moveable member is arranged to move away from its biased position on insertion of the pin. This allows the edges of the aperture in the latch plate to engage the pin whilst it is inserted into the connector and so provide resistance to removal of the pin as soon as a force is applied to remove the pin.

[0030] Preferably the biasing means comprises a spring. The strength of the spring may be selected according to the purpose of the locking connector

[0031] The spring may be a coil spring. In an alternative implementation, the spring is a leaf spring.

[0032] The spring may apply a torque to the biased moveable member by bearing on one face of the member on or adjacent one edge of the member, the member being restrained (or biased by another spring) by means bearing on the opposite face on or adjacent the opposite edge of the member. The spring may bear directly or indirectly via a shaft, the shaft preferably being coupled to the biased moveable member via an arrangement which permits pivoting.

[0033] This may provide a simple but effective mechanism by which the linear force produced by the spring may be translated effectively into a torsional force on the biased moveable member.

[0034] The movable member may be formed integrally with a spring. The movable member may be integral with a support member and formed from spring steel whereby the movable member is inherently biased to a said angled position. The movable member may comprise a latch plate and a support plate integrally formed with one another in a V shape formation whereby a force applied to the latch plate deflects the face of the latch plate towards a confronting surface of the support plate.

[0035] Preferably the connector further comprises a release mechanism for releasing the pin from the retaining mechanism and the locking connector. The ease with which the means for releasing the pin operates may vary according to the application for which the locking connector is used.

[0036] The means for releasing said pin may comprise a mechanism to reduce the magnitude of the forces applied to the pin by the moveable member. This may allow removal of the pin without damaging the locking mechanism of the connector. The release means may comprise a component in the form of an actuator for applying a force to counteract the biasing force. The release means may include a depressible button but alternatively it may comprise a recess into which a tool, such as a small screwdriver, can be inserted to apply a force. The release means preferably is operable from a front face of the connector socket.

[0037] Preferably, the connector further comprises means for providing an electrical connection to the pin, the pin being capable of carrying a current between the plug and the socket. This may allow the pin to be a functional pin which may be electrically connected to a power or signal line or to earth as well as securing the plug and socket.

[0038] Preferably, the pin is the earth pin of a plug. This may be advantageous since it allows the locking mechanism to operate on any standard plug, without requiring modification to the plug such as, for example, the addition of an extra pin for the locking connector to operate upon. A further advantage of this feature is that it may allow the mechanism to operate or be released safely without requiring disconnection from a live electricity supply.

[0039] In an embodiment, means may be provided for applying a retaining force to more than one of a plurality of pins in a single plug. This may allow the plug to be held more securely and may better inhibit unauthorised release. This may be applicable in the case of a multi-pin connector where an individual plug may not necessarily have a pin to be inserted into every available hole in a connector. Embodiments of the present invention will now be described by way of example only with reference to the accompanying diagrammatic drawings in which: -

[0040] Figure 2 is a perspective view of a locking connector socket in accordance with the present invention;

[0041] Figure 3 is a plan view of the housing of the socket of Figure 2;

[0042] Figure 4 is a side view of the housing of the socket of Figure 2;

[0043] Figure 5 is a view of the apertured end face of the socket of Figure 2;

[0044] Figure 6 is a perspective view of the earth pin aperture of the socket of Figure 2;

[0045] Figure 7 is a schematic view showing in cross section, part of the socket of Figure 2;

[0046] Figures 8 and 8a show in perspective part of the construction of Figure 7 and in more detail in Figure 8a;

[0047] Figure 9 is a plan view of the latch plate of the socket of Figure 2;

[0048] Figure 10 shows a first type of release mechanism for the socket of Figure 2;

[0049] Figure 11 shows a second type of release mechanism;

[0050] Figures 12 to 14 show respectively side, plan and perspective views of a terminal for receiving an inserted pin;

[0051] Figure 15 is an end view of a locking connector having the release mechanism of Figure 10; Figure 16 is an end view of a locking connector having the release mechanism of Figure 11 ;

[0052] Figure 17 is an end view of the combination of two sockets in accordance with the present invention but with one of the two sockets adapted to receive only a C14 type plug;

[0053] Figure 18 shows single and multi connector units of the present invention, each with an actuator end in a first position;

[0054] Figure 19 shows single and multi connector units of the present invention, each with an actuator end in a second position;

[0055] Figure 20 is a perspective view of a locking mechanism component in accordance with a second embodiment of the invention;

[0056] Figure 21 shows the mechanism of Figure 20 in situ in part of a connector socket;

[0057] Figure 22 shows a pair of latch plates for a third embodiment of the invention;

[0058] Figure 23 is a perspective view of the latch plates of Figure 22 installed in part of a connector, and

[0059] Figure 24 is a side view of the assembly of Figure 23.

[0060] A three pin socket connector 10 is of a type for panel mounting and comprises an outer housing 11 of rectangular shape and which comprises an apertured front flange 12 that extends outwards of the remainder of the housing to define an abutment face 13. The housing also comprises, on two opposite sides, a pair of deformable clip protrusions 14 whereby, when the socket is inserted into an apertured panel (not shown), it is held in position in known manner between the abutment faces 13 of the housing and abutment faces 15 of the clip protrusions 14.

[0061] Within the cavity 18 defined by the housing there is positioned a socket connector body 19 which is supported at a rear end by the housing 11 . The cavity space between the housing and connector body forms an insertion slot for receiving the outer sleeve of a shrouded plug.

[0062] The front face 20 of the body 19 comprises three T shaped apertures 21 each to receive a pin of a C14 or C20 plug.

[0063] Three pin receiving terminals 40 (see Figure 7) are located within the body 19 (see Figures 3 and 4) to engage with the inserted pins of a plug. The terminals comprise tabs 22 which extend from the rear of the housing for connection to a power supply.

[0064] The construction of the terminals within the body of the connector is shown in Figures 12 to 14. Each terminal comprises a pair of surfaces 41 which are positioned to confront one another, slightly spaced apart, such as to be suitable for engaging the pins of a C14 or C16 plug. Additionally, alongside that pair of terminal surfaces, there is provided a terminal surface 42 that extends generally parallel with the direction in which the aforementioned terminal surfaces are slightly spaced apart, that terminal being positioned for engaging with the pins of a C20 and C22 plug.

[0065] The body also provides location for a locking mechanism that is positioned to engage with the earth pin of an inserted plug.

[0066] In a manner substantially as employed in a connector the subject of our EP 1459412, the locking mechanism comprises a latch plate 25 which is resiliently biased to a tilted position by means of an actuator 32 and a compression spring 23 as best seem in Figures 7, 8 and 8a. In contrast to defining a conventional rectangular shaped aperture as provided by the invention of EP 1459412, the latch plate defines a T shaped aperture which is dimensioned to receive and engage with the earth pin of, for example, either a C14 or a C20 plug.

[0067] Also in contrast to the latch plate of EP 1459412, the latch plate of the subject socket comprises an aperture 26 which defines two pairs of pin engaging surfaces as shown in Figure 9. In this embodiment one pair of pin engaging surfaces 27 are spaced apart in a direction parallel with the direction in which the pin engaging surfaces of the other pair 28 are spaced apart.

[0068] The connector of this embodiment also differs significantly from the locking mechanism of EP 1459412, in that the latch plate is not pivotally supported for tilting about a pivot axis parallel with the direction in which the other two pin apertures of the socket are spaced apart. Instead it is pivotally supported for tilting about an axis Z perpendicular to the direction in which the other two pin apertures 21 of the socket are spaced apart.

[0069] Referring to Figure 9, a first pair of surfaces for engaging and seizing the earth pin of a C14 connector are the surfaces 27, these being engagable with the two larger faces of the rectangular cross section earth pin. The second pair of surfaces for engaging in seizing the earth pin of a C20 plug are the surfaces 28, these being engagable with the two smaller side faces of the earth pin.

[0070] The latch plate 25 has an edge 30 opposite to the pivot edge 31 and which is movable in unison with the actuator 32. Prior to insertion of an earth pin the actuator holds the latch plate 25 in a tilted position (as shown in Figure 7) under the action of the compression spring 23. When an earth pin enters the socket the pin deflects the tilted latch plate against the action of the compression spring whereby the opening defined by the aperture 26 of the latch plate becomes sufficient for the earth pin to fully enter the socket. When the plug is fully inserted the latch plate is in a plane substantially perpendicular to the direction of the pin insertion in consequence of the body of the plug bearing on one of the pairs of retention surfaces 27, 28. However, in the event of a small initial movement of the earth pin outwards from the socket the latch plate 25 tilts towards the front face of the socket, under the action of the compression spring, thereby to allow the pin engaging surfaces of one of the pairs 27, 28 of the latch plate to bear firmly against the pin and inhibit further outward movement of the plug.

[0071] In the event of requiring authorised removal of the plug the externally located end 35 of the actuator protrusion 36 is pressed against the action of the compression spring thereby to tilt the latch plate away from the tilted, locking position and allow withdrawal of the plug.

[0072] In the aforedescribed embodiment of the present invention the actuator protrusion 36 is positioned close to a corner of the forward facing flange. That position of the outer actuator protrusion typically will be convenient either for a single socket or an integrally formed pair of sockets as shown in Figure 17. In the construction shown in Figure 17 one of the sockets is of a multi-purpose type to receive either a C14 or a C20 plug but the other is of a conventional type to receive only a C14 plug. However for convenience and economy both sockets comprise a locking mechanism of the present invention.

[0073] Optionally the actuator protrusion 36 may be located in a different corner region of the front of the housing, as seen for example in the options of Figure 18.

[0074] However, for use in an installation having a different space availability for the connector, the actuator protrusion 36 may be located alongside one side region 38 of the socket body, for example as shown in the options of Figure 16 and Figure 19.

[0075] In the aforedescribed embodiment the latch plate 25 is resiliently biased to reside inherently in an inclined position under the action of a compression spring 23 that acts indirectly on the latch plate via an actuator 32. In a second embodiment of the invention (see Figures 20 and 21 ) the locking mechanism 40 comprises a latch plate that is integral with a support plate and relative to which it inherently lies in an inclined position. The integrally formed plates are of spring steel .

[0076] The locking member 40 comprises a support plate 42 formed with an aperture 43 through which an earth pin of either a C14 or a C20 plug may readily pass when the plate is installed in a connector to lie in a plane perpendicular to the direction of insertion of a plug pin.

[0077] The side edges 44, 45 of the support plate are held at fixed positions of the connector body 46.

[0078] The support plate 42 is integral with the latch plate 41 , in a V shaped configuration, and in consequence of being formed from spring steel a face of the apertured latch plate is able to be deflected in a direction towards a confronting face of the support plate when acted on by a plug that is attempting to enter through the latch plate aperture 47. The latch plate aperture defines to pairs of oppositely positioned pin retention surfaces whereby , as described in respect of the first embodiment of the invention, the latch plate is able to engage and inhibit withdrawal of the earth pin of either a C14 plug or a C20 plug.

[0079] The distal edge 49 of the latch plate locates in a groove 48 of the release mechanism actuator. Depression of the actuator moves the latch plate towards the support plate against the resilient bias force of the spring material and thereby permits withdrawal of an inserted plug pin.

[0080] In the aforedescribed embodiments the two pairs of pin retention surfaces are provided by a single latch plate having a T shaped aperture, with the plate being pivotally supported at one edge for pivotal movement about an axis parallel with the stem section of the T shape of the aperture. In a third embodiment of the invention two latch plates are provided in series with one another and each is engagable with a respective one of two types of pin. One of the latch plates allows the pin of one type of connector to extend freely therethrough but provides pin retention surfaces to secure the pin of a second type of connector.

[0081] Referring to Figures 22 to 24, a locking mechanism 50 comprises a first latch plate 51 having a T shaped aperture 52 and a second latch plate 53 having a rectangular shaped aperture 54.

[0082] Edges 55, 56 of the latch plates are pivotally supported at fixed positions by grooves 57, 58 in the connector body portion 59. Opposite edges of the latch plates are supported by grooves 62, 63 in a resiliently biased actuator component 64.

[0083] The aperture 52 of latch plate 51 defines pin engaging surfaces 66 for engaging with the pin of one type of connector. The aperture 54 of latch plate 53 has pin engaging surfaces 67 that retentively engage with the longer pin of a second type of connector.

[0084] Insertion of a pin in the direction X will result in captive engagement of the pin with one of the two plates as that plate is deflected to a reduced angle of inclination. Release from either of the latch plates is effected by movement of the actuator component in a direct opposite the direction X.

Claims

Claims.1 . A locking connector comprising a body which defines apertures each to receive pins which have the same, first, orientation as the pins of a C14 type plug and pins which have the same, second, orientation as the pins of a C20 type plug, the connector comprising a locking mechanism which is displaced by a plug pin upon insertion of the plug thereby to permit insertion of the plug but which seizes the pin on attempted withdrawal of the plug, said locking mechanism comprising a first pair of retention surfaces for engaging with a pin of a first orientation and a second pair of retention surfaces for engaging with a pin of a second orientation.

2. A locking connector according to claim 1 wherein the locking mechanism comprises a first pair of oppositely positioned pin retention surfaces and a second pair of oppositely positioned pin retention surfaces, the surfaces of one pair being spaced apart in a direction substantially at right angles to the direction in which the pin retention surfaces of the other pair are spaced apart.

3. A locking connector according to claim 1 or claim 2 wherein the connector comprises earth, live and neutral terminals and wherein the locking mechanism is arranged to engage with the earth pin of an inserted plug.

4. A locking connector according to any one of the preceding claims wherein each aperture if the front face of the body is of a T shape.

5. A locking connector according to any one of the preceding claims wherein the locking mechanism comprises at least one moveable member in the form of a latch plate.

6. A locking connector according to claim 5 wherein the latch plate defines an aperture within the outer profile of the latch plate.

7. A locking connector according to any one of claims 1 to 5 wherein the latch plate has an outer profile which at least in part defines a recess region which defines at least one pair of retention surface.

8. A locking connector according to any one of claims 5 to 7 wherein the latch plate defines an aperture of a T shape.

9. A locking connector according to claim 8 wherein the T shaped aperture defines two pairs of pin engagement surfaces.

10. A locking connector according to claim 8 or claim 9 wherein the T shaped aperture is pivotable about an axis parallel with the length of the stem section of the T shape.

11. A locking connector according to any one of claims 5 to 10 wherein the body defines live and neutral terminal apertures and wherein the latch plate is pivotable about an axis that is perpendicular relative to the direction in which said live and neutral apertures are spaced apart.

12. A locking connector according to any one of claims 5 to 11 wherein in the absence of an inserted pin, the latch plate resides inherently at an angle of between 10° and 20° relative to a plain that is perpendicular to the direction of insertion of the pin of a plug.

13. A locking connector according to any one of the preceding claims and comprising a moveable member which is resiliently biased and which may be deflected from a biased position by means of a release mechanism that acts against a biasing means thereby to permit removal of a plug from the connector.

14. A locking connector according to claim 13 wherein the release mechanism comprises a component operable from a front face of the connector.

15. A locking connector according to claim 13 or claim 14 wherein the biasing means comprises a spring.

16. A locking connector according to claim 15 wherein the spring applies a torque to the biased movable member by bearing directly on the movable member.

17. A locking connector according to claim 15 wherein the spring bears indirectly on the movable member.

18. A locking connector according to claim 16 wherein the movable member is formed integrally with a spring.

19. A locking connector according to claim 18 wherein the movable member comprises a latch plate and a support plate integrally formed with one another in a V shaped formation.

20. A locking connector according to any one of claims 1 to 8 wherein the locking mechanism comprises a first movable member that defines the first pair of retention surfaces and a second movable member that defines the second pair of retention surfaces.

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