Coaxial cable connector

Abstract

A cable connector 2 comprising, a connector body 4 having channel extending therethrough, the connector body having a forward section 18 (Figure 2) for connection to a reciprocal connector and a rearw

Description

FIELD

[0001] The present disclosure relates to a cable connector for a coaxial cable. In particular, the present disclosure relates to a fluid-proof coaxial cable connector. BACKGROUND

[0002] Co-axial cable is used to transmit radio-frequency signals. These cables comprise an inner conductive core which transmits the primary data signal. This core is commonly metallic and may comprise multiple strands of wire that enable data transmission. Covering this core is a dielectric insulator, which is commonly formed from polymeric materials. Surrounding this insulator is a conductive shield, which is commonly formed of metallic material and may be constructed from braided metallic fibres. This conductive shield serves to electromagnetically insulate the core from external sources of noise. This conductive shield is encased by an outer sheath, which serves to isolate the internal elements of the cable from exterior factors such as physical damage, electrical current and fluid ingress.

[0003] Co-axial connectors enable two different co-axial cables to be joined together. Primarily these connectors serve to join the two cable cores together such that data can be transmitted between the two cables. This is achieved by the soldering a male pin to the core of one cable and a reciprocal female pin to the core of another cable. The male pin is then inserted into the female pin to enable the transmission of the data signal. Co-axial connectors also have a housing that serves to electrically connect the shielding of one cable to the shield of another, and also include interlocking elements that secure two mating connectors together to prevent the disconnection of the male and female pins. Finally, a dielectric insulating element is retained within the housing, which receives the male or female pin and electrically isolates it from the housing.

[0004] Coaxial data transmission cables commonly comprise a data transmitting element surrounded by a form of shielding that protects the data transmitting element from electromagnetic interference. When forming a connection between two cables, any connectors must form independent connections between the data transmitting elements and the shielding. The shield and data transmission elements utilise materials that are highly electrically conductive; such as silver, copper, and gold. Whilst some of these materials have a degree of corrosion resistance (e.g. gold) they all exhibit a reduction in conductivity when exposed to corrosive environments.

[0005] Data transmission cables are frequently used in humid environments and can be used in situations where elements of the connector are immersed in fluid. A seal is commonly positioned between the mating surfaces of two connectors, to prevent moisture ingress into the front of either connector. However, this seal only functions when the two connectors are mated, meaning connectors are vulnerable to internal corrosion when unconnected. Furthermore, seals of this type do not provide any protection against moisture ingress at the rear of the connectors (i.e. the cable entry point where the cable enters the connector housing). The shield is commonly connected to the connector housing proximate this rear location, where only limited protection is provided by the crimping of the cable housing to the cable. Thus, the connection between the shields is afforded little protection against corrosion.

[0006] In presently known arrangements, prior to connecting the pin to the core of the coaxial cable a conductive ferrule is passed over the end of the cable. A section of the outer sheath is then removed to expose the braided metal fibres of the shield. These fibres are unwoven and pulled backward to expose the insulator. A portion of this insulator is then removed to expose the core. The exposed core can be inserted into a recess in the pin and soldered or crimped in place. The resultant pin / core assembly is inserted into the connector housing, after which the ferrule is passed along the cable. As the ferrule passes along the cable, it forces the fibres towards and into contact with the housing. The ferrule is then passed over this contact area to cover the exposed fibres / housing and is crimped in place to form an electrical connection between the housing and the metal shield.

[0007] Due to the removed insulator, typically a length of core conductor is left unshielded once the pin has been secured in place. This exposed length of core can result in a signal loss due to the lack of electromagnetic shielding. Whilst the break is covered by the housing, there is still signal loss as the housing will be of a larger diameter and will offer varying degrees of shielding.

[0008] It is therefore desirable to provide an improved coaxial cable connector which addresses the above described problems and / or which offers improvements generally. SUMMARY

[0009] According to the present invention there is provided a cable connector as described in the accompanying claims.

[0010] In an embodiment of the invention there is provided a cable connector comprising a connector body having channel extending axially therethrough, the connector body having a forward section for connection to a reciprocal connector and a rearward section for receiving and housing the cable. An electrically conductive connection pin is axially arranged within the channel in the forward section of the connector body, the pin having a distal connector end, being the front end, for electrical connection with a reciprocal connector and a proximal cable end, being the rear end, for connection to the cable arranged rearwardly of the connector end. The terms forward and rearward are relative and relate to the front or forward end being the end that is connected to the reciprocal connector. A pin seal located about the pin within the forward section of the channel and arranged to provide a seal between the pin and the body. A resilient cable seal is located within the channel in the rear end of the connector body, the cable seal comprising a radially outer surface in sealing engagement with the channel in the rear end of the connector body and a cable channel for receiving the cable, the cable channel defining a radially inner surface that seals against the cable, such that the cable seal forms a seal between the body and the cable.

[0011] Forming an internal pin seal at the front end of the connector prevents internal water ingress via the front face of the connector when the connector is open (i.e. unconnected). The cable seal creates a seal at the rear of the connector between the connector body and the cable, and hence prevents liquid ingress into the connector via the rear cable entry point. Therefore, the above arrangement significantly improves the corrosion resistance of the connector through the provision of front end and rear end sealing.

[0012] The connector body may comprise a main body and a rear end cap or cover connected to the main body. The main body may have a channel for receiving the cable seal, and the rear cap may retain the cable seal within the channel. Thus, the rear cap may cover the end of the channel and may extend over the main body such that: the rear seal is positioned in a radially central position, the main body is in a radially intermediate position, and the rear cap is in a radially outer position. The rear cap includes an axial end wall, the inner surface of which axially compresses the cable seal when the rear cap is connected to the main body. Connection comprises the cap being moved axially from a first rearward position to a second forward position. A stop element may located within the channel of the main body that engages and axially locates the inner end of the cable seal. The cable seal is compressed between the stop element and the rear end cap. The stop element is any feature within the channel that abuts with the seal to prevent further forward movement. The stop element may be a shielding element, which may itself be located against a radial projection of the channel defining a further stop element.

[0013] The rear cap may comprise a cable receiving section having an inner channel sized to receive the coaxial cable. The co-axial cable may be received in a close fit.

[0014] The cable receiving section may be configured to plastically deform (i.e. capable of undergoing non-elastic deformation) against a coaxial cable received in the inner channel. Plastic deformation may take the form of a crimping operation.

[0015] The main body may comprise an external threaded portion located on an outer surface and the rear end cap comprises a corresponding internal threaded portion located on an inner surface that engages with the external threaded portion of the main body. Threading the cap onto the body moves the cap from the rearward position to the forward position and compresses the cap against the seal.

[0016] The cable seal may comprise a radial outer surface and a plurality of radially projecting ribs from the radial outer surface that are configured to engage and seal with the inner wall of the channel.

[0017] The cable seal may comprise a rear end face having an annular protuberance projecting therefrom, the annular protuberance surrounding the cable opening. The annular protuberance may be a raised ring integrally moulded with the seal. The ring is radially spaced outwardly from the inner channel of the seal and inwardly of the outer surface.

[0018] The pin seal may be arranged rearwardly of the distal end of the pin and forwardly of the stop element and may be compressed against a forward face of the stop element within the channel.

[0019] The rear end cap may be axially adjustable from the first rearward axial position to the second forward axial position forwardly of the first axial position via the threaded connection with the body and the cable seal is compressed between the stop element and the rear end cap as the rear end cap moves forwardly to the second axial position.

[0020] Compressing the seal in this manner causes radial expansion, inwardly and outwardly against the cable and channel respectively which improves sealing with both. Specifically the cable seal may be cylindrical having a radially outer surface and a radially inner surface and the cable seal expands radially inwards and radially outwards when compressed such that the radially outer surface and an radially inner surface are urged into sealing engagement with the channel of the main body and the cable respectively.

[0021] The cable may be a co-axial cable; the co-axial cable comprises a conductive core, an insulator covering the core, and a conductive shield covering the insulator; and the cable end of the pin is configured to connect to the conductive core.

[0022] The pin seal may comprise an assembly of seal elements including a rear seal element, and intermediate compressible seal element and a front seal element, and one of the seal elements, which may be the intermediate seal element, may compressed for example between the front and rear seal elements to radially expend the intermediate seal element, thus forming a seal between the pin and the channel. The stop element may comprise a radial step formed by a reduction in the channel diameter and the intermediate seal is compressed against the stop element by the front seal element.

[0023] The pin seal may be formed of a dielectrically insulating material.

[0024] In another aspect of the disclosure there is provided a coaxial cable connector for a coaxial cable comprising a conductive core, an insulator covering the core, a conductive shield covering the insulator, and an outer layer. The connector further comprises an electrically conductive connector body having channel extending axially therethrough, the connector body having a forward section for connection to a reciprocal connector and a rearward section for receiving and housing a portion of the coaxial cable. A connection pin is axially arranged within the channel at least partially in the forward section of the connector body, the pin having a distal connector end for electrical connection with a reciprocal connector and a proximal cable end configured to receive for electrical connection with the core of the coaxial cable. An electrically conductive shielding element is located within the channel at the cable end of the pin, the shielding element having a channel extending therethrough for receiving an end portion of the cable. The channel is axially aligned with the connection pin such that the core of the coaxial cable is able to extend through the shielding element into electrical engagement with the pin. The shielding element is electrically isolated from the pin, is in electrical engagement with the connector body, and is for electrical connection to the conductive shield of the coaxial cable.

[0025] The cable end of the connection pin may be configured to electrically connect to the core of the coaxial cable. The shielding element may have a forward end and a rearward end, wherein the forward end may be in electrical engagement with the connector body and the rearward end may be in electrical engagement with the conductive shield. The positioning of the shielding element within the body allows an electrical connection to be formed closer to the connection pin. As the shielding element is electrically isolated from the core of the cable, no current passes from the shielding element to the core, and as such the electrical signals carried by the shield and core and kept separated.

[0026] The coaxial cable connector may further comprise an insulating element arranged to electrically isolate the pin from the shielding element.

[0027] The shielding element may have a forward end and a rearward end, the forward end has a front face including an axially extending recess and the insulating element is at least partially received within the recess.

[0028] The insulating element may be in abutment with the cable end of the pin and includes a channel extending therethrough having a diameter sized to receive the cable core. By virtue of the insulating element being in abutment with the cable end of the pin, the shielding element is brought into close proximity with the pin, whilst not engaging in electrical contact with the pin. Thus the shielding provided by the co-axial cable is brought as close to the core / pin connection as physically possible.

[0029] The insulating element may have an outer diameter that is smaller than the outer diameter of the front face, such that the insulating element is spaced radially inwards of the channel.

[0030] The shielding element may comprise a front section having a first diameter, and a rear end having a second diameter smaller than the first diameter, the connector may further comprise a conductive collar received about the rear section of the shielding element and arranged such that the collar surrounds at least part of the rear section and extends rearwardly of the rear section to cover the connection between the coaxial cable and the rear section. Therefore, the soldered connection is protected from damage and further the shielding of the cable is brought partially rearwardly such that the soldered connection is covered by the shielding, reducing signal loss. The conductive collar may be a conductive shielding collar, in that it extends the cable shielding over the solder joint. The conductive collar may be slidably received about the rear section. The conductive collar may axially extend rearwardly of the rear section.

[0031] The front section of the shielding element may be in electrical connection with the connector body such that when the conductive shield of the coaxial cable is connected to the rear section of the shielding element an electrical pathway is formed between the conductive shield and the connector body.

[0032] The conductive collar may be slidably received about the rear section of the shielding element.

[0033] The front section may be located within the channel at an axial position and the diameter of the front section corresponds to the diameter of the channel at the axial position of the front section.

[0034] The diameter of the front section and the diameter of the channel at the axial position of the front section may be dimensioned to form an interference fit therebetween. An interference fit between the front section and the channel can improve electrical conductivity between the body and the shielding element, such that signal loss is reduced.

[0035] A stop element may be formed within the channel that engages with the front end of the shielding element to axially locate the shielding element within the channel. The term "axially locate" refers to prevention of further axial movement. This reference to "axially locate" relates to preventing the shielding element from passing further into the channel.

[0036] The stop element comprises a radial projection within the channel extending to a position radially inwards of the outer diameter of the front section. The stop element can be a stepped section of the body.

[0037] The coaxial cable connector may further comprise a rear cap secured to the rear end of the connector body and a sealing element located within the channel between the rear cap and the shielding element.

[0038] The sealing element may be compressed between the rear cap and the shielding element. Compression of the sealing element may axially locate the shielding element within the channel. This reference to "axially locate" relates to preventing the shielding element from passing out of the channel. The compression of the sealing element may urge the sealing element against the stop element.

[0039] The coaxial cable connector may further comprise a coaxial cable for carrying an electronic signal, wherein the core of the cable is connected to the cable end of the pin, and the conductive shield is secured to the rear end of the shielding element.

[0040] The conductive shield may secured to the rear end of the shielding element at a connection region and the collar covers at least a portion of the rear section of the shielding element and the connection region. The securement of the conductive shield to the shielding element may be in the form of a soldered joint. The soldering of the top hat to the metal shield results in a strong connection that transfers any mechanical force from the core / pin solder joint (of conventional connectors) to this stronger joint thus reducing the chance of detachment of the pin. The conductive shield may be compressed between the collar and the shielding element. Such compression will result in the securement of the conductive shield relative to the shielding element without requiring soldering.

[0041] The rear section of the shielding element may be configured to pass beneath and expand the conductive shielding. Cutting the conductive shielding of a cable to length risks introducing damage (e.g. cuts), which may result in a loss of electromagnetic shielding performance. By passing beneath and expanding the conductive shielding, the risk of damage is significantly reduced.

[0042] The rear section of the shielding element may be formed as a cone. The rear section of the shielding element may taper inwardly as the rear section extends away from the front section of the shielding element. This tapering and / or cone shape eases assembly by allowing the shielding element to radially expand the conductive shield. The rear section may have a taper angle between 5 and 10 degrees and more preferably approximately 6 degrees. The rear section may have a cone angle between 5 and 10 degrees and more preferably approximately 6 degrees. The cone angle and / or taper angle depends on the cable for use with the connector. An angle of 5 to 10 degrees has been found to be suitable for most cables, with an angle of 6 degrees resulting in improved assembly of connector to high frequency cables. DESCRIPTION OF DRAWINGS

[0043] The present disclosure will now be described by way of example only with reference to the following illustrative figures in which: Figure 1 shows a schematic perspective representation of a connector according to an aspect of the present disclosure; Figure 2 shows a cross-sectioned schematic perspective representation of a connector body according to an aspect of the present disclosure; Figure 3 shows a schematic perspective representation of a connector seal according to an aspect of the present disclosure; Figure 4 shows an exploded schematic perspective representation of a connector shield termination arrangement according to an aspect of the present disclosure; Figure 5 shows a schematic perspective representation of a connector male pin according to an aspect of the present disclosure; Figure 6 shows an exploded schematic perspective representation of a connector sub-assembly according to an aspect of the present disclosure; Figure 7 shows a cross-sectioned schematic perspective representation of a male pin connector and shield termination soldered sub-assembly according to an aspect of the present disclosure; Figure 8 shows a cross-sectioned schematic perspective representation of a connector according to an aspect of the present disclosure; Figure 9 shows a schematic perspective representation of a connector according to an aspect of the present disclosure; Figure 10 shows a cross-sectioned schematic perspective representation of a connector body according to an aspect of the present disclosure; Figure 11 shows a schematic perspective representation of a connector female pin according to an aspect of the present disclosure; Figure 12 shows an exploded schematic perspective representation of a connector sub-assembly according to an aspect of the present disclosure; Figure 13 shows a cross-sectioned schematic perspective representation of a connector according to an aspect of the present disclosure; and Figure 14 shows a cross-sectioned schematic perspective representation of two mated connectors according to an aspect of the present disclosure; Figure 15 shows an exploded schematic perspective representation of a connector shield termination arrangement according to an aspect of the present disclosure; Figure 16 shows a cross-sectioned schematic perspective representation of a male pin connector and shield termination soldered sub-assembly according to an aspect of the present disclosure; DESCRIPTION OF EMBODIMENTS

[0044] The following description presents exemplary embodiments and, together with the drawings, serves to explain principles of the disclosure. The scope of the disclosure is not intended to be limited to the precise details of the embodiments or exact adherence with all method steps. Variations will be apparent to a skilled person and are deemed also to be covered by the description. Terms for features used herein should be given a broad interpretation that also encompasses equivalent functions and features. In some cases, several alternative terms (synonyms) for structural features have been provided but such terms are not intended to be exhaustive.

[0045] Descriptive terms should also be given the broadest possible interpretation; e.g. the term "comprising" as used in this specification means "consisting at least in part of" such that interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner. Directional terms such as "vertical", "horizontal", "up", "down", "upper" and "lower" are relative terms that may be used for convenience of explanation usually with reference to the illustrations and are not intended to be ultimately limiting if an equivalent function can be achieved with an alternative dimension and / or direction.

[0046] The description herein refers to embodiments with particular combinations of configuration steps or features. However, it is envisaged that further combinations and cross-combinations of compatible steps or features between embodiments will be possible. The description of multiple features in relation to any specific embodiment is not an indication that such features are inextricably linked, and isolated features may function independently from other features and not necessarily require implementation as a complete combination.

[0047] An SMA plug connector 2 is shown in Figure 1. The plug connector 2 comprises a body 4, a rear cover or cap 6, a coaxial cable 8, a coupler 10, and a male pin 12. The plug connector 2 is axially symmetric around a connection / plugging axis 14, being the axis along which a corresponding jack is inserted into the plug connector 2. The coupler 10 has an external hexagonal profile that enables it to be received within and operated by a wrench.

[0048] Referring to Figure 2, the body 4 has a central body section 16 from which a front body section 18 and back body section 20 extend in opposing directions. The central body section 16 has an outer hexagonal form for engagement with a wrench. The front body section 18 extends forwardly from the central body section 16 to a front end 22 and the back body section 20 extends rearwardly to a back end 24. The back body section 20 has an external body thread 26 for engagement with the rear cover 6. The external body thread 26 extends between the back end 24 of the body and the rear face of the central body section 16. A central bore 28 defines a channel that extends axially through the body 4, along the plugging axis 14, from the front end 22 to the back end 24. A radially extending flange section 29 is located proximate the front end 22. A radial recess 30 is formed in the external surface of the body 4 inboard of the flange 29, the recess extending radially into the front body section 18.

[0049] The diameter of the central bore 28 varies as it extends through the body 4. The bore 28 has a first diameter extending inwardly from the first end 22. The bore 38 has a stepped reduction in diameter that defines a separation rib 32 at an axial position immediately preceding the central body section 16. This internal rib 32 notionally separates the bore 28 into a front bore section 28a and a back bore section 28b that are connected at the separation rib 32. The back bore section 28b extends from the separation rib 32 to the back end 24 and has a stepped diameter. The back bore section 28b includes an inner back bore section 34 located axially adjacent the separation rib 32 and substantially within the central body section 16, having a diameter greater than the diameter of the separation rib 32. The diameter is then increased to define an axially outer back bore section 36 that extends to the back end 24 and defines the rear opening to the connector 2. The front bore section 28a extends from the separation rib 32 to the front end 22 and forms the front opening to the connector 2.

[0050] Referring to Figure 3, a rear seal 40 is shown. The rear seal 40 is substantially cylindrical in nature having an inner channel 42 extending axially along its length from an inner sealing face 44 to an outer sealing face 46. Four radial ribs 48a-d are defined on the outer surface 50 of the main body of the seal 40. The radial ribs 48a-d are annular in shape extending around the outer circumference of the seal 40 and are spaced along its axial length, the ribs being interspaced with a series of corresponding channels. An annular protuberance 52 is formed on the inner sealing face 44 of the seal and is radially located between the inner channel 42 and the outer surface of the respective rib 48a. The annular protuberance 52 projects axially and defines an inner end face sealing element. The rear seal 40 is formed as a single integral component, formed of a resilient material such as silicone or rubber. The ribs are integrally formed (such as by moulding) with the main body.

[0051] Referring to Figure 4, a shielding element 54 is shown. The shielding element 54 is an assembly comprising a dielectric washer 54a, a shielding ring 54b and a cable cap 54c. Unlike the dielectric washer 54a, the shielding ring 54b and cable cap 54c are both electrically conductive. The shielding ring 54b has a bore 56 that passes through its centre, which is slightly larger than the outer diameter of the coaxial cable 8. Thus, the shielding ring 54b is configured to receive the coaxial cable 8 and can pass freely along the outer surface of the coaxial cable 8. The dielectric washer 54a has a bore 58 passing through its centre. The cable cap 54c comprises a front section 60 with a front face 62, and a back section 64 that axially extends backwardly from the cable cap front section 60 to a back face 66. The front section 60 has a greater diameter than the back section 64 and forms a flange at the front of the back section 64, such that the cable cap 54c has a 'top hat' form, being substantially t-shaped in cross section. A bore 68 extends through the cable cap 54c. A recess 70 is arranged at the front face 62 that is co-axial with the bore 68 and extends partially into the front section 54c. The bore 68 extends through the cable cap 54c, whilst the recess 70 terminates within the front section 60. The recess is configured to receive the dielectric washer 54a, having a diameter corresponding to the dielectric washer and a depth corresponding to the thickness of the washer 54a. The diameter of the back section 64 of the cable cap 54c is smaller than channel 56 of the shielding ring 54b, such that the back section 64 is able to be received within the channel 56 in a close fit. The outer diameter of the front section 60 is substantially the same as that of the shielding ring 54b. As such the shielding ring 54b can pass onto, but not past, the back section 64 of the cap section 54c and the front section 54c and the shielding ring 54b form a contiguous cylinder.

[0052] Referring to Figure 5, a male pin 12 of the connector 2 has a main body 74, a reduced diameter distal end section 76 and a tapered tip 78. A solder flow channel 80 extends into the pin 12 from the rear end of the pin and terminates within the main body 74. A solder entry aperture 82 is formed in the main body 74 proximate the rear end 72. The solder entry aperture 82 enables the flow of solder into the solder flow channel 80 from the outer surface of the main body 74.

[0053] An exploded sub-assembly 84 of the plug connector 2 is shown in Figure 6. By virtue of the exploded view, the internal elements of the rear cover 6 are visible. The rear cover 6 comprises a rear body 86 in the form of a hex nut and a cable receiving section 88 in the form of a spigot extending from the rear of the rear main body 86. The cable receiving section 88 has an inner channel 90 sized to receive the coaxial cable 8 in a close fit. The rear cover 6 has an internal thread 94 at its front end that threads onto the external thread 26 at the rear end of the body 4. The coaxial cable 8 is processed for soldering and as such the internal elements of the coaxial cable 8 are shown as exposed.

[0054] The coaxial cable 8 has a typical construction comprising a conductive cable core 96 that in normal use carries the data signal. Surrounding this cable core 96 is internal electromagnetic cable shielding 98, which comprises an outer conductive cable shield 98a and an inner dielectric cable insulator 98b. The cable shielding 98 is encapsulated by a non-conductive outer cable sheath 100. The cable sheath 100 has been removed at a connection end of the coaxial cable 8 to expose the cable shielding 98. A portion of the cable shielding 98 has similarly been removed towards the connection end to expose a length of the cable core 96.

[0055] The coaxial cable 8 extends through the inner channel 90 and through the rear main body 86 with the exposed cable core 96 being located forwardly of the rear main body 86. On the front side of the rear main body 86 the rear seal 40 is inserted over the coaxial cable 8, which is received through the inner channel 42 and the seal 40 is arranged such that the annular protuberance 52 faces rearwardly towards the rear cover 6. The shielding ring 54b is inserted over the free end of the coaxial cable 8 and onto the cable sheath 100. The dielectric washer 54a is inserted into the recess 70 in the front face 62 of the cable cap 54c, and the cable core 96 is passed through the cable cap channel 68 from the cable cap back face 66, and then through the dielectric washer 54a. The cable core 96 is inserted into the solder flow channel 80 of the male pin 12 and the cable insulator 98b is received within the cable cap bore 68.

[0056] Parts of the sub-assembly 84 are soldered together, as shown in Figure 7. With the exposed cable core 96 inserted in the male pin 12, solder is passed through the solder entry aperture 82 and flows into the solder flow recess 80. The solder flows down the solder flow recess 80 between the male pin 12 and the cable core 96 and solders the cable core 96 to the male pin 12. The rear end 64 of the cable cap 54c is then soldered to an uncovered portion of the conductive cable shield 98a. The resultant soldered joint 102 forms an electrical connection between the cable cap 54c and the conductive cable shield 98a. The shielding ring 54b is then slid forwardly from a rearward position along the coaxial cable 8 into contact with the cable cap 54c such that the soldered joint 102 is at least partially covered by the shielding ring 54b.

[0057] This shielding element 54 of this soldered sub-assembly 84 has several benefits over existing cable construction techniques. As the conductive cable cap 54c is soldered to the cable shielding 98a it forms a continuation of the electromagnetic shielding. Consequently, electromagnetic shielding extends continuously along the cable 8 to the point of contact between the cable core 96 and the male pin 12 at the front end of the conductive cable cap 54c. Additionally, this design provides an improved and more robust mechanical connection between the cable 8 and the body 4 compared to equivalent externally crimped solutions. Soldering the shielding element 54 to the metal shield results in a strong connection that transfers any mechanical force from the core / pin solder joint (of conventional connectors) to this stronger joint thus reducing the chance of detachment of the pin. Furthermore, the coverage afforded by the shielding ring 54b beneficially extends to cover the area of solder adjacent the cable cap 54c, where the shielding 98a of the cable 8 has been severed, and reduces electromagnetic interference in this region.

[0058] A cross-sectional view of an assembled plug connector 2 is shown in Figure 8. The coupler 10 has an inner bore 104 including an internal thread 106 at a front end. An internal radial channel 108 is formed within the inner bore 104 and rearwardly from the internal thread 106. The radial channel 108 is aligned with a corresponding channel 30 on the body section 18. The coupler 10 is retained on the front body section 18 by a retaining ring 109 that sits within the aligned channels 108,30. The internal thread 106 extends beyond the front end 22 of the front body section 18 and is arranged to be engaged with a reciprocal external thread of a further component such a SMA jack for example.

[0059] Dielectric sealing elements 110 are located in the channel of the front body section 18. The dielectric sealing elements 110 consist of a dielectric seal 110a sandwiched between a front dielectric insulator 110b and a rear dielectric insulator 110c. The front dielectric insulator 110b is sized to have an interference fit with the diameter of the front bore section 28a and is push-fitted into the front bore section 28a. Each of the dielectric seal 110a, front dielectric insulator 110b, and a rear dielectric insulator 110c, respectively have an axial bore 112a, 112b, 112c corresponding in diameter to the male pin. The male pin 12 is inserted through each of the co-axial dielectric sealing elements 110.

[0060] During assembly of the plug connector 2 the dielectric sealing elements 110 are inserted into the front bore section 28a. The rear dielectric insulator 110c is inserted until it abuts the separation rib 32. The dielectric seal 110a is then abutted against the rear dielectric insulator 110c, after which the front dielectric insulator 110b is pressed into place in abutment with the dielectric seal 110a. Pressing the front dielectric insulator 110b into place causes the dielectric seal 110a to be compressed between the rear dielectric insulator 110c and the front dielectric insulator 110b. Consequently the dielectric seal 110a expands radially into engagement with the front bore section 28a to create a first fluid-proof seal with the body 4.

[0061] The sub-assembly 84 is then connected via the rear of the body 4. The male pin 12 passes through the back bore section 28b and through the dielectric sealing elements 110, until the front face 62 of the cable cap 54c abuts the separation rib 32, which acts as a stop element to locate the cable cap 62. The insertion of the male pin 12 through the axial passageway 112a causes a second fluid-proof connection between the male pin 12 and the dielectric seal 110a. The first and second fluid-proof connections act together to create a front fluid-proof seal within the front bore section 28a. A front O-ring 114 is positioned upon the front body section 18, within the coupler 10. This enables any reciprocal connector (e.g. an SMA jack) to form a supplementary fluid-proof connection against the connector 2 as it is screwed into engagement, thereby further increasing the fluid-proofing capacity at the front body section.

[0062] The front fluid-proof seal ensures that, regardless of whether mated or unmated, fluid ingress from the front of the connector 2 is inhibited. The receipt of the male pin 12 within the dielectric sealing elements 110 results in the male pin 12 being electrically isolated from the body 4.

[0063] The cable cap 54c is soldered to the cable shielding 98a and is located within the body 4 of the connector 2. The cable cap 54c is also in engagement with the body 4 at an internal location (at least by virtue of the engagement of the cable cap 54c with the separation rib 32). The cable cap 54c is dimensioned such that it forms an interference fit with the back bore section 36 at the internal location. By virtue of forming an interference fit, the cable cap 54c and cable shielding 98a attached thereto are at least partially retained in place regardless of the compression provided by the rear seal 40. Additionally, each of these features improves the electromagnetic shielding of the connector 2 and further they interact to provide additional improvements to the electromagnetic shielding of the cable 8.

[0064] The rear cover 6 is then screwed onto the body section 4 with the internal thread 94 engaging with the external body thread 26. The resultant forward axial translation of the rear cover 6 urges the rear seal 40 into the back bore section 36. When the seal 40 is fully inserted it is axially sandwiched between the rear cover 6 and the shielding ring 54b. As the rear cover 6 is further tightened onto the body 4 the rear seal 40 is axially compressed and consequently expands radially outwards, such that each of the rear seal radial ribs 48a-d compress against the wall of the outer back bore section 36. This resiliently biassed engagement forms a third fluid-proof connection between the body 4 and the rear seal 40. As the rear seal 40 is compressed it also expands radially inwards sealing against the coaxial cable 8. Thus, a fourth fluid-proof connection is formed between the rear seal 40 and the coaxial cable 8, which together with the third fluid-proof connection forms a rear fluid-proof seal in the back body section 20. As the rear seal 40 is compressed the annular protuberance 52 is pressed into axial engagement with inner rear face of the rear cover 6 and is compressed against it. This compression creates an auxiliary fluid-proof connection between the rear seal 40 and the rear cover 6, increasing the fluid-proofing capacity at the rear of the plug connector 2.

[0065] To secure the connector 2 relative to coaxial cable the rear the cable receiving element 88 of the rear cover 6 is hexagonally crimped onto the coaxial cable 8, which improves cable retention and provides strain relief at the rear of the plug connector 2. By crimping the rear cover 6 to the cable 8, any relative rotational movement between the cable 8 and rear cover 6 is prevented. Thus, the risk of such rotation breaking the rear fluidproof seal at the rear of the body 4 is addressed. Additionally, the crimping prevents axial movement of the cable 8 relative to the body 4. This reduces the risk of the core 96 being pulled from the pin 12 should force be applied to the cable 8. To improve the locking capacity between the rear cover 6 and the body 4, thread lock can be applied to at least one of the internal cover thread 94 and the external body thread 26, prior to engagement of said threads.

[0066] The rear fluid-proof seal ensures that fluid ingress at the rear of the body 4 is inhibited. Combined with the front fluid-proof seal, and the positioning of the soldered portions of the cable 8 between the front and rear fluid-proof seals, the soldered portions are effectively isolated from fluid ingress regardless of whether the connector 2 is mated. Thus, corrosion of the soldered joints is mitigated.

[0067] Referring to Figure 9 an SMA jack connector 116 is shown. The jack connector 116 comprises a body 120, a rear cover 122, a coaxial cable 124, a nut 128, a shake proof washer 130, and an external O-ring 132. The rear cover 122, and coaxial cable 124 of the jack connector 116, are identical to the rear cover 6, and coaxial cable 8 of the plug connector 2. The nut 128 has a hexagonal outer profile for engagement with a wrench and a threaded bore 134.

[0068] Referring to Figure 10, a jack connector 116 has a body 120 with a central body section 138 from which a front body section 140 and back body section 142 extend in opposing axial directions. The central body section 138 has an outer hexagonal form for engagement with a wrench. The front body section 140 extends forwardly to a front end 144 and the back body section 142 extends rearwardly to a back end 146. The front body section 140 has a front external body thread 148 for engagement with a reciprocal connector (e.g. an SMA plug), and the back body section 142 has a back external body thread 150 for engagement with the rear cover 122. A central bore 152 extends axially through the body 120, from the front end 144 to the back end 146. An annular recess 154 extends axially rearwardly into the central body section 138.

[0069] As the central bore 152 passes through the body 120 the bore diameter varies. Within the central body section 138 the central bore 152 has a reduced diameter that defines a separation rib 156 within the central body section 138. This separation rib 156 serves to separate the central bore 152 into a front bore section 152a and a back bore section 152b that are contiguous. The back bore section 152b extends from the separation rib 156 towards the back end 146 to define an inner channel section 158. The back bore section 152b then increases in diameter and continues to extend to the back end 146 to define a rear channel section 160. The front bore section 152a extends from the separation rib 156 to the front end 144.

[0070] Referring to Figure 11, a female pin 161 has a main body 164 from which a tapered female tip 168 extends. A solder flow recess 170 extends from a back end 162 and terminates within the main body 164. A solder entry aperture 172 is formed in the main body 164 that enables the flow of solder into the solder flow recess 170 from the outer surface of the main body 164. A female channel 174 extends inwardly from the front end of the female pin face.

[0071] An exploded sub-assembly 176 of the jack connector 116 is shown in Figure 12. The rear seal 178, and shielding element 180 of the jack connector 116, are identical to the rear seal 40, and shielding element 54 of the plug connector 2. The jack connector 116 subassembly 176, and the plug connector 2 sub-assembly 84, are identical except for the replacement of the male pin 12 with the female pin 161. The connection of the female pin 161 to the cable core 96 occurs in the same manner as that of the connection of the male pin 12 to the cable core 96.

[0072] A cross-sectional view of an assembled jack connector 116 is shown in Figure 13. The jack connector 116 includes dielectric sealing elements 182 (182a, 182b, 182c). Dielectric sealing elements 182 of the jack connector 116, are identical to dielectric sealing elements 110 of the plug connector 2. The assembly of the jack connector 116 occurs in substantially the same way as the assembly of the plug connector 2. Consequently, the resultant formation of fluid-proof connections and fluid-proof seals also occurs in the same manner. However, the coupler 10, retaining ring 109, and front O-ring 114, of the plug connector 2 are not present in the jack connector 116 and thus the associated assembly steps are not performed for the jack connector 116.

[0073] The assembled jack connector 116 is shown mounted to a mounting structure 184 having a mounting hole 186 passing from a first mounting face 188 to a second mounting face 190. Prior to mounting, the external O-ring 132 is first passed along the front body section 140. The external O-ring 132 has a diameter configured such that it passes into and sits within the annular recess 154. The front body section 140 can then be passed through the mounting hole 186 until the external O-ring 132 enters engagement with the first mounting face 188. The shake proof washer 130 is then passed along the front body section 140, followed by the threading of the nut 128 onto the front external body thread 148. Tightening of the nut 128 urges the shake proof washer 130 against the second mounting face 190, consequently drawing the central body section 138 towards the mounting structure 184 and compressing the external O-ring 132 between the annular recess 154 and the first mounting face 188. This compression results in a fluid-proof seal being formed between the first mounting face 188 and the external O-ring 132.

[0074] The jack connector 116 and plug connector 2 can be connected together, as shown in Figure 14. This connection can also occur when the jack connector 116 is mounted to a mounting structure 184. The jack connector 116 and plug connector 2 are arranged such that the jack axis 118 and plugging axis 14 are aligned and co-linear. The front end 144 of the jack connector 116 is then advanced towards the plug connector 2 until the jack connector 116 and plug connector 2 enter engagement. The internal thread 106 is then threaded onto the front external body thread 148 of the jack connector 116, such that rotation of the coupler 10 causes the jack connector 116 to advance within the coupler channel 104. During this advancement the tip 78 of the male pin 12 enters the female channel 174 of the female pin 161. Continued rotation of the coupler 10 causes the front end 144 of the jack connector 116 to enter engagement with, and subsequently compress, the front O-ring 114 of the plug connector 2 to create a seal.

[0075] The dielectric seal 110a, 182a and the rear seal 40,178 are both selected for their mechanical properties. Importantly, the material of the dielectric seal 110a, 182a and rear seal 40,178 enables them to be readily deformed to fill any voids between the body 4,120 and pin 12,161, and body 4,120 and cable 8,124, respectively. The use of an elastomeric material beneficially enables the connector 2,116 to be repeatedly assembled and disassembled. The body 4,120, rear cover 6,122, and coupler 10 are manufactured from gold plated brass, SUS304 or SUS316. These materials have been found to be most suited for the harsh environments in which the connector 2 may need to operate.

[0076] Referring to Figure 15 a shielding element 254 for use with any of the previously described connectors is shown. The shielding element 254 is an assembly comprising a dielectric washer 254a, a shielding ring 254b and a cable cap 254c. The shielding ring 254b and cable cap 254c are both electrically conductive, whilst the dielectric washer 254a is not. However, the shielding ring 254b need not necessarily be electrically conductive for the shielding element 254 to function.

[0077] The cable cap 254c comprises a front section 260 with a front face 262, and a back section 264 that axially extends rearwardly from the cable cap 254c front section 260 to a back face 266. The front section 260 has a greater diameter than the back section 264 and forms a flange at the front of the back section 264, such that the cable cap 254c has a 'top hat' form, being substantially t-shaped in cross section. The back section 264 tapers inwardly from the front section 260 to the back face 266, such that the diameter of the back section 264 adjacent the front section 260 is larger than the diameter of the back section 264 at the back face 266. The resultant form of the back section 264 can be described as 'cone-shaped'. A bore 268 extends through the front section 260 and back section 264 of the cable cap 254c. The bore 268 is dimensioned to allow the cable cap 254c to pass over the insulator 98b of the co-axial cable 8, but not to pass over the cable shielding 98a and outer sheath 100 of the co-axial cable 8.

[0078] A recess 270 is arranged at the front face 262 that is co-axial with the bore 268 and extends partially into the front section 260, before terminating therein. The recess 270 is configured to receive the dielectric washer 254a and has a diameter corresponding to the outer geometry of the washer 254a and a depth corresponding to the thickness of the washer 254a. The dielectric washer 254a has a bore 258 passing through its centre for receiving the core 96 of a co-axial cable 8.

[0079] The shielding ring 254b has a bore 256 that passes through its centre, which is slightly larger than the outer sheath 100 of the coaxial cable 8. Thus, the shielding ring 254b is configured to receive the coaxial cable 8 and can pass freely over the outer sheath 100 of the coaxial cable 8. The diameter of the back section 264 of the cable cap 254c is smaller than channel 256 of the shielding ring 254b, such that the back section 264 is passable through the channel 256. The outer diameter of the front section 260 is substantially the same as that of the shielding ring 254b and greater than the bore 256. As such the shielding ring 254b cannot pass forwardly of the back section 264 of the cable cap 254c, and the front section 260.

[0080] Referring to Figure 16, a sub-assembly 284 for use with any of the previous connectors is shown. A portion of the cable shielding 98a and cable insulator 98b is removed from the front of the co-axial cable 8 to expose the cable core 96. The shielding ring 254b is then slid along the cable 8, after which the cable cap 254c is passed onto the end of the cable.

[0081] The back section 264 of the cable cap 254c passes over the dielectric insulator of the cable 8 and underneath the cable shielding 98a. As the cable cap 254c is moved further onto the cable its tapered geometry causes the cable shielding 98a to expand radially. The radial expansion of the cable shielding 98a eases installation of the cable cap 254c onto the coaxial cable 8 as it avoids the need to mechanically cut the cable shielding 98a such that is passes over the back section 264 of the cable cap 254c. Whilst radial expansion may induce splaying of the cable shielding 98a, this will not affect the electro-magnetic insulating performance of the cable shielding 98a. When the back section 264 of the cable cap 254c is fully inserted underneath the cable shielding 98a, the end of the cable shielding 98a engages with the front section 260 of the cable cap 254c. Further insertion of the cable through the cable cap 254c causes the cable shielding 98a to splay further and cover the rear face of the front section 260.

[0082] The dielectric washer 254a is then passed onto the exposed cable core 96 and into the recess 270 of the cable cap 254c. Thus, the cable core 96 is dielectrically insulated from the cable cap 254c. The remainder of the exposed cable core 96 is inserted into the solder flow recess 80 of a male pin 12. Solder is then passed through the solder entry aperture 82 and flows into the solder flow recess 80 to solder the cable core 96 to the male pin 12. To complete the sub-assembly 284 the shielding ring 254b is then slid along the cable towards the cable cap 254c and into engagement with the cable shielding 98a.

[0083] When this sub-assembly 284 is installed within the above-mentioned connectors, the rear seal 40 provides a compressive force against the shielding ring 254b, which in turn compresses the cable shielding 98a against the front section 260. This forms a strong electrical connection between the cable cap 254c and the cable shielding 98a. However, additional connections may be formed (for example between the cable shielding 98a and the shielding ring 254b). Whilst the above-mentioned connectors include a rear seal 40 for waterproofing, it will be appreciated that alternative connectors may provide compression by any appropriate means (e.g. when the cable cap 254c and shielding ring 254b are both in an interference fit with the housing). The electrical connection may be improved by virtue of soldering the cable shielding 98a to the cable cap 254c and / or the shielding ring 254b. Such a soldered joint may also provide mechanical retention of the cable shielding 98a upon the cable cap 254c, replacing the compressive induced connection in connectors including a rearward compression element (such as a rear seal 40).

[0084] The shielding element 254 of this sub-assembly 284 has several benefits over existing cable construction techniques. The connection between the cable cap 254c and the cable shielding 98a forms a continuation of the electromagnetic shielding. Consequently, electromagnetic shielding extends continuously along the cable 8 to the point of contact between the cable core 96 and the male pin 12 at the front end of the conductive cable cap 254c. Additionally, this design provides an improved and more robust mechanical connection between the cable 8 and the body 4 compared to equivalent externally crimped solutions.

Claims

1. A cable connector comprising,a connector body having channel extending axially therethrough, the connector body having a forward section for connection to a reciprocal connector and a rearward section for receiving an end portion of the cable;a connection pin axially arranged within the channel in the forward section of the connector body, the pin having a distal connector end for electrical connection with a reciprocal connector and a cable end for connection to the cable arranged rearwardly of the connector end;a pin seal located about the pin within the forward section of the channel and arranged to provide a seal between the pin and the body; anda cable seal located within the channel in the rear end of the connector body, the cable seal comprising a radially outer surface in sealing engagement with the channel of the connector body, and a cable channel for receiving the cable, the cable channel defining a radially inner surface that seals against the cable such that the cable seal forms a seal between the body and the cable.

2. A cable connector according to claim 1 wherein the connector body comprises a main body having the channel and a rear end cap for retaining the cable seal within the channel, wherein the rear end cap is connected to the main body.

3. A cable connector according to claim 2 wherein the rear cap includes an end wall that axially compresses the cable seal when the rear cap is connected to the main body.

4. A cable connector according to claim 2 or 3 wherein a stop element is located within the channel of the main body that engages and axially locates the inner end of the cable seal, and the cable seal is compressed between the stop element and the rear end cap.

5. A cable connector according to claim 2 to 4 wherein the main body comprises an external threaded portion located on an outer surface and the rear end cap comprises a corresponding internal threaded portion located on an inner surface that engages with the external threaded portion of the main body.

6. A cable connector according to any one of claims 2 to 5 wherein the cable seal comprises a radial outer surface and a plurality of radially projecting ribs from the radial outer surface.

7. A cable connector according to claim 6 wherein the cable seal comprises a rear end face having an annular protuberance projecting therefrom, the annular protuberance surrounding the cable opening.

8. A cable connector according to any one of claims 4 to 7 wherein the pin seal is arranged rearwardly of the distal end of the pin and forwardly of the stop element.

9. A cable connector according to any one of claims 4 to 8 wherein the rear end cap is axially adjustable from a first axial position to a second axial position forwardly of the first axial position and wherein the cable seal compressed as the rear end cap moves to the second axial position.

10. A cable connector according to any one of claims 4 to 9 wherein the cable seal is cylindrical having a radially outer surface and an radially inner surface and the cable seal expands radially inwards and radially outwards when compressed such that the radially outer surface and an radially inner surface are urged into sealing engagement with the channel of the main body and the cable respectively.

11. A cable connector according to any preceding claim wherein the pin seal comprises an assembly of seal elements including a rear seal element, and intermediate compressible seal element and a front seal element, and wherein the intermediate seal element is compressed between the front and rear seal elements to radially expend the intermediate seal element to form a seal between the pin and the channel.

12. A cable connector according to claim 1 wherein the pin seal is formed of a dielectrically insulating material.CLAIMS01 10 251. A cable connector comprising,a main body having a channel extending axially therethrough, the main body 5 having a forward section for connection to a reciprocal connector and a rearwardsection for receiving an end portion of the cable;a connection pin axially arranged within the channel in the forward section of the connector body, the pin having a distal connector end for electrical connection with a reciprocal connector and a cable end for connection to the cable arranged10 rearwardly of the connector end;a pin seal located about the pin within the forward section of the channel and arranged to provide a seal between the pin and the body; anda cable seal located within the channel in the rear end of the connector body, the cable seal comprising a radially outer surface in sealing engagement with the15 channel of the connector body, and a cable channel for receiving the cable, the cablechannel defining a radially inner surface that seals against the cable such that the cable seal forms a seal between the body and the cable; anda rear end cap for retaining the cable seal within the channel, the rear end cap connected to the main body; wherein20 the rear end cap includes an end wall that axially compresses the cable sealwhen the rear end cap is connected to the main body; andthe cable seal is configured to radially expand when axially compressed such that the radially outer surface and the radially inner surface are urged into sealing engagement with the channel of the main body and the cable respectively.25 2. A cable connector according to claim 1 wherein a stop element is located within thechannel of the main body that engages and axially locates the inner end of the cable seal, and the cable seal is compressed between the stop element and the rear end cap.01 10 253. A cable connector according to claim 1 or 2 wherein the main body comprises an external threaded portion located on an outer surface and the rear end cap comprises a corresponding internal threaded portion located on an inner surface that engages with the external threaded portion of the main body.5 4. A cable connector according to any one of claims 1 to 3 wherein the cable sealcomprises a radial outer surface and a plurality of radially projecting ribs from the radial outer surface.

5. A cable connector according to claim 4 wherein the cable seal comprises a rear end face having an annular protuberance projecting therefrom, the annular protuberance10 surrounding the cable opening.

6. A cable connector according to any one of claims 2 to 5 wherein the pin seal is arranged rearwardly of the distal end of the pin and forwardly of the stop element.

7. A cable connector according to any one of claims 2 to 6 wherein the rear end cap is axially adjustable from a first axial position to a second axial position forwardly of the15 first axial position and wherein the cable seal compressed as the rear end cap movesto the second axial position.

8. A cable connector according to any one of claims 2 to 7 wherein the cable seal is cylindrical.

9. A cable connector according to any preceding claim wherein the pin seal comprises20 an assembly of seal elements including a rear seal element, and intermediatecompressible seal element and a front seal element, and wherein the intermediate seal element is compressed between the front and rear seal elements to radially expend the intermediate seal element to form a seal between the pin and the channel.25 10. A cable connector according to claim 1 wherein the pin seal is formed of adielectrically insulating material.

11. A cable connector according to any preceding claim wherein the cable seal is configured to expand radially inwards towards the cable and radially outwards towards the channel of the main body when axially compressed.

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