Patent Application
20120202372
The subject matter herein relates generally to connector assemblies.
Radio frequency (RF) connector assemblies have been used for numerous applications including military applications and automotive applications, such as global positioning systems (GPS), antennas, radios, mobile phones, multimedia devices, and the like. The connector assemblies are typically coaxial cable connectors that are provided at the end of coaxial cables.
In order to standardize various types of connector assemblies, particularly the interfaces for such connector assemblies, certain industry standards have been established. One of these standards is referred to as FAKRA. FAKRA is the Automotive Standards Committee in the German Institute for Standardization, representing international standardization interests in the automotive field. The FAKRA standard provides a system, based on keying and color coding, for proper connector attachment. Like jack keys can only be connected to like plug keyways in FAKRA connectors. Secure positioning and locking of connector housings is facilitated by way of a FAKRA defined catch on the jack housing and a cooperating latch on the plug housing.
The connector assemblies include a center contact and an outer contact that provides shielding for the center contact. The outer contact is typically manufactured from a zinc die-cast or screw machined part, which is expensive to manufacture. The connector assemblies also include ferrules that are terminated to the cables. The ferrules are typically manufactured by a drawn method or screw machining, which may be expensive to manufacture.
A need remains for a connector assembly that may be manufactured in a cost effective and reliable manner. Additionally, a need remains for a connector assembly that may utilize less expensive parts, such as stamped and formed parts, in existing outer housings and locks made for die-cast parts.
In one embodiment, a connector assembly is provided having a center contact configured to be terminated to a center conductor of a cable. A dielectric holds the center contact. A stamped and formed outer contact surrounds the dielectric and the center contact. The outer contact is configured to be terminated to a braid of the cable. A stamped and formed outer ferrule surrounds at least a portion of the outer contact such that the braid is sandwiched between the outer ferrule and the outer contact.
In another embodiment, a connector assembly is provided having a center contact configured to be terminated to a center conductor of a cable. A dielectric holds the center contact. An outer contact surrounds the dielectric and the center contact. The outer contact is configured to be terminated to a braid of the cable. A cavity insert surrounds the outer contact and is axially secured with respect to the outer contact to hold the outer contact therein. The cavity insert has a flange. The center contact, dielectric, outer contact and cavity insert define a subassembly. The connector assembly includes an outer housing having a cavity that receives the subassembly. The flange is locked into the outer housing to hold the axial position of the subassembly within the cavity.
In a further embodiment, a connector assembly is provided having a center contact configured to be terminated to a center conductor of a cable. A dielectric holds the center contact. An outer contact surrounds the dielectric and the center contact. The outer contact has an inner ferrule segment that is configured to be terminated to a braid of the cable. The inner ferrule segment has an axially extending gap. The size of the gap is controllable to control an impedance of the connector. An outer ferrule surrounds the inner ferrule segment of the outer contact such that the braid is sandwiched between the outer ferrule and the inner ferrule. The outer ferrule is crimped to control the size of the gap in the inner ferrule segment.
The jack assembly 102 has a mating end 110 and a cable end 112. The jack assembly 102 is terminated to the cable 106 at the cable end 112. The plug assembly 104 has a mating end 114 and a cable end 116. The plug assembly 104 is terminated to the cable 108 at the cable end 116. During mating, the mating end 110 of the jack assembly 102 is plugged into the mating end 114 of the plug assembly 104.
In the illustrated embodiment, the jack assembly 102 and the plug assembly 104 constitute FAKRA connectors which are RF connectors that have an interface that complies with the standard for a uniform connector system established by the FAKRA automobile expert group. The FAKRA connectors have a standardized keying system and locking system that fulfill the high functional and safety requirements of automotive applications. The FAKRA connectors are based on a subminiature version B connector (SMB connector) that feature snap-on coupling and are designed to operate at either 50 Ohm or 75 Ohm impedances. The connector system 100 may utilize other types of connectors other than the FAKRA connectors described herein.
The jack assembly 102 has one or more keying features 118 and the plug assembly 104 has one or more keying features 120 that correspond with the keying features 118 of the jack assembly 102. In the illustrated embodiment, the keying features 118 are ribs and the keying features 120 are channels that receive the ribs. Any number of keying features may be provided, and the keying features may be part of the standardized design of the FAKRA connector.
The jack assembly 102 has a latching feature 122 and the plug assembly 104 has a latching feature 124. The latching feature 122 is defined by a catch and the latching feature 124 is defined by a latch that engages the catch to hold the jack assembly 102 and the plug assembly 104 mated together.
The jack assembly 102 includes a center contact 140, a dielectric 142, an outer contact 144, an outer ferrule 146, a cavity insert 148, an optional cable insert 150 and an outer housing 152. In the illustrated embodiment, the center contact 140 constitutes a pin contact, however other types of contacts are possible in alternative embodiments. The center contact 140 is terminated to the center conductor 130 of the cable 106. For example, the center contact 140 may be crimped to the center conductor 130.
The dielectric 142 receives and holds the center contact 140 and possibly a portion of the center conductor 130. The outer contact 144 receives the dielectric 142 therein. The outer contact 144 surrounds the dielectric 142 and at least a portion of the center contact 140. The outer contact 144 provides shielding for the center contact 140, such as from electromagnetic or radio frequency interference. In an exemplary embodiment, the outer contact 144 is stamped and formed, which makes the outer contact 144 less expensive than manufacturing the outer contact by other methods, such as die-casting or screw machining. The dielectric 142 electrically isolates the center contact 140 from the outer contact 144. The outer contact 144 is configured to be electrically connected to the cable braid 134 thereby providing continuous shielding.
The outer ferrule 146 is configured to be crimped to the cable 106. The outer ferrule 146 provides strain relief for the cable 106. In an exemplary embodiment, the outer ferrule 146 is configured to be crimped to the cable braid 134 and the cable jacket 136. For example, the outer ferrule 146 may be crimped to the cable braid 134 and the cable jacket 136 using an F-crimp or another type of crimp. Because the outer contact 144 is stamped and formed, the outer contact 144 tends to be a thinner metal than a die-cast or screw machined part, and the crimp of the outer ferrule 146 should be performed in a manner that does not crush the outer contact 144 and the center conductor 130.
The cavity insert 148 surrounds at least a portion of the outer contact 144 and is axially secured with respect to the outer contact 144 to hold the outer contact 144 therein. The cavity insert 148 is received within the outer housing 152 and is held therein by a lock 154. The cavity insert 148 is used to hold the true position of the outer contact 144 within the outer housing 152. The cavity insert 148 has a predetermined outer perimeter that corresponds with the outer housing 152 such that the cavity insert 148 is configured to be secured within the outer housing 152. Optionally, different cavity inserts 148 having different internal diameters and features may be provided to receive different sized outer contacts 144 therein and to hold the different sized outer contacts 144 within the outer housing 152. Optionally, a family of jack assemblies may be provided, with some of the jack assemblies having die-cast or screw machined outer contacts that are configured to be held in a particular outer housing 152. The cavity insert 148 is dimensioned the same as the die-cast or screw machined outer contacts such that the cavity insert 148 and stamped and formed outer contact 144 may be used within the same outer housing 152 as the die-cast or screw machined outer contacts, thus reducing the part count of the product family.
The cable insert 150 is positioned rearward of the cavity insert 148 and surrounds a portion of the cable 106 and/or portions of the outer contact 144 and outer ferrule 146. The cable insert 150 is used to hold a true position of the outer contact 144 and cable 106 in the outer housing 152.
The center contact 140, dielectric 142, outer contact 144, outer ferrule 146, cavity insert 148 and optionally the cable insert 150 define a jack subassembly 156 that is configured to be loaded into the outer housing 152 as a unit. The outer housing 152 includes a cavity 158 that receives the jack subassembly 156. The lock 154 holds jack subassembly 156 in the cavity 158.
The plug assembly 104 includes a center contact 180, a dielectric 182, an outer contact 184, an outer ferrule 186, a cavity insert 188, an optional cable insert 190 and an outer housing 192. In the illustrated embodiment, the center contact 180 constitutes a socket contact, however other types of contacts are possible in alternative embodiments. The center contact 180 is terminated to the center conductor 170 of the cable 108. For example, the center contact 180 may be crimped to the center conductor 170.
The dielectric 182 receives and holds the center contact 180 and possibly a portion of the center conductor 170. The outer contact 184 receives the dielectric 182 therein. The outer contact 184 surrounds the dielectric 182 and at least a portion of the center contact 180. The outer contact 184 provides shielding for the center contact 180, such as from electromagnetic or radio frequency interference. In an exemplary embodiment, the outer contact 184 is stamped and formed, which makes the outer contact 184 less expensive than manufacturing the outer contact by other methods, such as die-casting or screw machining. The dielectric 182 electrically isolates the center contact 180 from the outer contact 184. The outer contact 184 is configured to be electrically connected to the cable braid 174.
The outer ferrule 186 is configured to be crimped to the cable 108. The outer ferrule 186 provides strain relief for the cable 108. In an exemplary embodiment, the outer ferrule 186 is configured to be crimped to the cable braid 174 and the cable jacket 176. For example, the outer ferrule 186 may be crimped to the cable braid 174 and the cable jacket 186 using an F-crimp or another type of crimp. Because the outer contact 184 is stamped and formed, the outer contact 184 tends to be a thinner metal than a die-cast or screw machined part, and the crimp of the outer ferrule 186 should be performed in a manner that does not crush the outer contact 184 and the center conductor 170.
The cavity insert 188 surrounds at least a portion of the outer contact 184 and is axially secured with respect to the outer contact 184 to hold the outer contact 184 therein. The cavity insert 188 is received within the outer housing 192 and is held therein by a lock 194. The cavity insert 188 is used to hold the true position of the outer contact 184 within the outer housing 192. The cavity insert 188 has a predetermined outer perimeter that corresponds with the outer housing 192 such that the cavity insert 188 is configured to be secured within the outer housing 192. Optionally, different cavity inserts 188 having different internal diameters and features may be provided to receive different sized outer contacts 184 therein and to hold the different sized outer contacts 184 within the outer housing 192. Optionally, different types of jack assemblies may be provided and offered to customers as a family, with some of the jack assemblies having die-cast or screw machined outer contacts that are configured to be held in a particular outer housing 192. The cavity insert 188 is dimensioned the same as the die-cast or screw machined outer contacts such that the cavity insert 188 and stamped and formed outer contact 184 may be used within the same outer housing 192 as the die-cast or screw machined outer contacts, thus reducing the part count of the product family.
The cable insert 190 is positioned rearward of the cavity insert 188 and surrounds a portion of the cable 108 and/or portions of the outer contact 184 and outer ferrule 186. The cable insert 190 is used to hold a true position of the outer contact 184 and cable 108 in the outer housing 192.
The center contact 180, dielectric 182, outer contact 184, outer ferrule 186, cavity insert 188 and optionally the cable insert 190 define a plug subassembly 196 that is configured to be loaded into the outer housing 192 as a unit. Other components may also be part of the plug subassembly 196. The outer housing 192 includes a cavity 198 that receives the plug subassembly 196. The lock 194 holds plug subassembly 196 in the cavity 198.
The dielectric 182 extends between a front 200 and a rear 202. The dielectric 182 has a cavity 204 that receives the center contact 180. The dielectric 182 includes a flange 206 that extends radially outward therefrom. Optionally, the flange 206 may be approximately centrally located between the front 200 and the rear 202. The flange 206 is used to position the dielectric 182 within the outer contact 184.
The outer contact 184 has a mating end 208 at a front 210 thereof and a cable end 212 at a rear 214 thereof. The outer contact 184 has a cavity 216 extending between the front 210 and the rear 214. In an exemplary embodiment, the outer contact 184 is stamped and formed from a flat workpiece that is rolled into a barrel shape. The barrel shape may be stepped. The barrel shape may be generally cylindrical or cylindrical along different portions. The flat workpiece has a first end 218 and a second end 220 that are rolled toward one another into the barrel shape until the first and second ends 218, 220 oppose one another. A seam 222 is created at the interface between the first and second ends 218, 220. The first and second ends 218, 220 may touch one another at the interface of the seam 222. Optionally, the first and second ends 218, 220 may be secured together at the seam 222 to hold the barrel shape.
The barrel shape is stepped along the length of the outer contact 184 to define shoulders 224. When the dielectric 182 is loaded into the cavity 216, the flange 206 engages the shoulder 224 to axially position the dielectric 182 with respect to the outer contact 184. In an exemplary embodiment, the outer contact 184 may include one or more retention tabs 226 that extend into the cavity 216 to engage the dielectric 182 to hold the dielectric 182 in the outer contact 184. For example, the rear facing surface of the flange 206 may engage the shoulder 224, while the retention tab 226 may engage the front facing surface of the flange 206 such that the flange 206 is captured between the shoulder 224 and the retention tab 226 to hold the axial position of the dielectric 182 within the outer contact 184. Other types of securing or positioning elements may be used in alternative embodiments for positioning or securing the dielectric 182 in the outer contact 184.
The outer contact 184 has a plurality of contact beams 228 at the mating end 208. The contact beams 228 are deflectable and are configured to be spring loaded against the outer contact 144 (shown in
The outer contact 184 includes a positioning tab 232 extending radially outward therefrom. The positioning tab 232 is configured to engage the cavity insert 188 to axially position the outer contact 184 with respect to the cavity insert 188. The cavity insert 188 includes a channel 234 that receives the positioning tab 232. Optionally, the channel 234 may be elongated such that the outer contact 184 may be rotated within the cavity insert 188. Other types of securing or positioning elements may be used in alternative embodiments for positioning or securing the outer contact 184 in the cavity insert 188.
The outer contact 184 has an inner ferrule segment 236 at the cable end 212. The cable braid 174 is configured to be terminated to the inner ferrule segment 236, as described in further detail below. In an exemplary embodiment, a gap 238 is defined along the seam 222 between the first and second ends 218, 220 of the inner ferrule segment 236. The size of the gap 238 is variable to change a diameter of the inner ferrule segment 236. For example, the gap 238 may be closed to decrease the diameter of the inner ferrule segment 236. The gap 238 extends generally axially along the inner ferrule segment 236 at the seam 222. In an exemplary embodiment, the gap 238 extends along a tortuous path defined by fingers 240 extending from the first end 218 and fingers 242 extending from the second end 220. The fingers 240, 242 are interdigitated with the gap 238 therebetween. Optionally, more than one gap may be provided along the inner ferrule segment 236.
Changing the size of the gap 238 changes the radius of the outer conductor surrounding the center conductor 170 and/or center contact 180, thereby controlling the capacitance between inner and outer conductors, and controlling the impedance. The size of the gap 238 (e.g., the distance between the first end 218 and the second end 220 along the inner ferrule segment 236) defines the amount of air exposure and thus changes the effective dielectric constant between the inner and outer conductors. By controlling the size of the gap 238, the impedance may be controlled along the path of the center conductor 170 and/or center contact 180 extending through the inner ferrule segment 236. For example, by reducing the size of the gap 238 (e.g., by squeezing the inner ferrule segment 236 to position the first end 218 closer to the second end 220) the impedance may be decreased. A target impedance, such as 50 ohms, may be achieved by controlling the size of the gap 238.
As explained in further detail below, the size of the gap 238 may be controlled by the outer ferrule 186. For example, by crimping the outer ferrule 186 around the inner ferrule segment 236, the inner ferrule segment 236 may be squeezed to close the gap 238. Additionally, by closing the gap 238 the diameter of the inner ferrule segment 236 is decreased. By decreasing the diameter of the inner ferrule segment 236, the inner surface of the inner ferrule segment 236 is positioned relatively closer to the center conductor 170 and/or the center contact 180, which will also affect the impedance.
In an alternative embodiment, rather than being stamped and formed, the outer contact 184 may be made by another manufacturing method and provided with a seam, at least along the inner ferrule segment, such that the diameter of the inner ferrule segment may be changed. For example, the outer contact 184 may be die-cast, extruded, screw machined, and the like, and then provided with a seam and gap along the inner ferrule segment. The outer ferrule 186 can then be used to change the diameter of the inner ferrule segment and thus control the impedance.
The cavity insert 188 includes a front 250 and a rear 252. The cavity insert 188 has a cavity 254 extending between the front 250 and the rear 252. The cavity insert 188 includes flanges 256 that extend circumferentially around the cavity insert 188. The flanges 256 are configured to be received within the outer housing 192 to engage surfaces in the outer housing 192 to hold the axial position of the cavity insert 188 with respect to the outer housing 192. The lock 194 engages the flange 256 to hold the cavity insert 188 in the cavity 198 of the outer housing 192.
The cavity insert 188 includes a sleeve 258 at the front 250. The sleeve 258 circumferentially surrounds the front 210 of the outer contact 184. The sleeve 258 is positioned radially outward of the contact beams 228 and protects the contact beams 228, such as during loading of the jack subassembly 156 into the outer housing 192 and/or during mating of the plug assembly 104 with the jack assembly 102.
The cable insert 190 is optionally used with the plug assembly 104. The cable insert 190 includes a front 260 and a rear 262 the cable insert 190 includes a cavity 264 extending between the front 260 and the rear 262. Optionally, the cable insert 190 may have a split design with two halves that are coupled around the cable 108. The cable insert 190 includes a plurality of ribs 266 that extend longitudinally or circumferentially. The ribs 266 define surfaces that are configured to engage corresponding surfaces of the outer housing 192 to hold the axial and/or rotational position of the cable insert 190 within the outer housing 192. When assembled, the cable insert 190 may surround the outer ferrule 186.
The outer ferrule 186 is stamped and formed from a flat workpiece having a first end 270 and a second end 272. The outer ferrule 186 is formed into an open barrel shape, such as a U-shape that has an open top 274. The outer ferrule 186 defines a channel 276. The cable 108 may be received in channel 276 and then the outer ferrule 186 may be crimped to the cable 108.
The outer ferrule 186 includes a braid segment 278 and a jacket segment 280. The braid segment 278 is provided at a front 282 of the outer ferrule 186 and the jacket segment 280 is provided at a rear 284 of the outer ferrule 186. The braid segment 278 is configured to be crimped around the inner ferrule segment 236 and the cable braid 174. The jacket segment 280 is configured to be crimped around the cable jacket 176. The outer ferrule 186 may include notches or serrations 286 that define surfaces that engage the cable braid 174 and/or cable jacket 176 to help hold the axial position of the outer ferrule 186 with respect to the cable 108. The outer ferrule 186 provides strain relief for the cable 108.
As described in further detail below, crimping the braid segment 278 may affect the size of the gap 238. Crimping the braid segment 278 may close the inner ferrule segment 236. The crimp height of the braid segment 278 may be controlled to control the amount of closure of the gap 238.
The outer housing 192 extends between a front 290 and a rear 292. The lock 194 is loaded through a side 294 of the outer housing 192. The latching feature 124 is provided along a top 296 of the outer housing 192. The outer housing 192 has a generally boxed shape outer profile. The cavity 198 is generally a cylindrical bore extending through the outer housing 192. The cavity 198 may have steps, shoulders and/or channels formed therein for receiving and holding the cavity insert 188 and/or the cable insert 190.
During assembly, the dielectric 182 is loaded into the outer contact 184 through the front 210 of the outer contact 184. The dielectric 182 is pushed into the cavity 216 until the flange 206 engages the shoulder 224. The retention tabs 226 (shown in
The cavity insert 188 is loaded onto the outer contact 184. The cavity insert 188 is loaded over the rear 214 until an inner ring 308 of the cavity insert 188 engages the shoulder 224. The interference between the inner ring 308 and the shoulder 224 holds the axial position of the cavity insert 188 with respect to the outer contact 184.
Once the cavity insert 188 is positioned over the outer contact 184, the center contact 180 is loaded into the dielectric 182. The cable 108 and center contact 180 are loaded through the rear 214 of the outer contact 184 and into the dielectric 182. The center contact 180 is loaded into the dielectric 182 through the rear 202. A flange 304, on the center contact 180, engages a shoulder 306 in the cavity 204 of the dielectric 182 to axially position the center contact 180 within the dielectric 182. As the cable 108 is coupled to the outer contact 184, the cable dielectric 172 is received in the inner ferrule segment 236 of the outer contact 184. The cable braid 174 is placed along the outside of the inner ferrule segment 236.
The braid segment 278 is crimped to the cable braid 174 (shown in
In an exemplary embodiment, as described above, the inner ferrule segment 236 includes a gap 238 (shown in
The cavity insert 326 is shorter than the cavity insert 188 (shown in
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.
