Patent Application
20130109221
Various embodiments relate to electrical terminals for facilitating electrical connectivity, and receptacle assemblies comprising electrical terminals.
Electrical terminals are used in a number of applications to facilitate electrical connecting of one element to another. Some electrical terminals may be configured to facilitate use with a removable connector of the type that may be repeatedly inserted and removed or otherwise configured to repeatedly engage and disengage the electrical terminal. The ability of the electrical terminal to facilitate electrical connectivity with such a removable connector can be problematic if an electrical connection area between the terminal and connector has poor connectivity, particularly when tolerance variations or degradation from repeated use causes a mating arrangement between the components to become loose or otherwise insecure.
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
The charging receptacle 30 may be configured to facilitate establishment of an electrical connection between a plurality of electrically conducting elements of the vehicle charging system 22 and the charging station 24. The charging receptacle 30 may facilitate the desired electrical connection by providing interconnecting conducting elements and/or by guiding the vehicle charging system 22 and conducting elements of the connector assembly 28 into a mating arrangement with each other. The charging receptacle 30 may be configured to support a multiple pin or port connection methodology for facilitating electrically interconnecting the vehicle charging system 22 and the conducting elements of the connector assembly 28, including but not limited to that specified in Society of Automotive Engineer (SAE) J1772 and International Electrotechnical Commission (IEC) 51851.
The charging system 20 and the particular components disclosed in
Referring now to
An electrically conductive terminal 46 is received within the receptacle 40. In the depicted embodiment, the terminal 46 contacts the receptacle 40 for providing an electrical connection between the terminal 46 and the receptacle 40. As stated above, the housing 38 may include wiring for providing an electrical connection to the terminal 46.
The terminal 46 has a generally cylindrical body 48 that is received within the receptacle 40. The terminal 46 may be formed of an electrically conductive spring metal, such as a spring tempered alloy or a binary metal such as copper clad steel. The cylindrical body 48 is formed with an outer diameter that is greater than an inner diameter of the receptacle 40 for a press or friction fit within the receptacle 40. The body 48 has a lengthwise slit 50 formed through the body 48 so that the body 48 is under compression when installed in the receptacle 40. In the depicted embodiment a proximate end 52 of the body 48 of the terminal 46 is installed against the blind depth end 44 of the receptacle 40. Additionally, the terminal 46 may be bonded to the receptacle housing 38 by sonic welding or any suitable manufacturing process.
The terminal 46 has an intermediate region 54 with a plurality of beams or leaf springs 56 oriented generally in a radial array and extending lengthwise from the body 48 toward the receptacle opening 42. Each leaf spring 56 has a first angled portion 58 that extends centrally inward and longitudinally away from the body 48. Additionally, each leaf spring 56 has a second angled portion extending radially outward from the first angled portion 58 and extending toward the receptacle opening 42. The leaf springs 56 are spaced apart circumferentially with gaps 62 between consecutive leaf springs 56. Although the first and second angled portions 58, 60 are illustrated and described, any suitable geometry, such as curved leaf springs may be utilized.
A retention member 64 is provided on a distal end of each leaf spring 56 extending longitudinally toward the receptacle opening 42 from the second angled portion 60. The leaf springs 56 are collectively under compression upon installation whereby the retention members 64 have an unloaded outside diameter that exceeds the inner diameter of the receptacle 40. When installed as illustrated in
The receptacle assembly 34 also includes a retainer 66 secured to the receptacle opening 42 for reducing a diameter of the receptacle opening 42. The retainer 66 may be similar to an embodiment disclosed in U.S. patent application Ser. No. 13/214,376 filed on Aug. 22, 2011 by Mott et al., which is incorporated by reference herein. The retainer 66 may be insulated to prevent inadvertent electrical communication with the opening end of the receptacle housing 38. The retainer 66 has a shoulder 68 abutting the opening 42. The retainer 66 also has a body 69 extending into the receptacle 40 with a tapered surface 70 which may extends centrally within the retention member 64 of the terminal 46. The retainer 66 has a reduced inner diameter 72 and a leading-edge 74 for guiding a pin 76 into the receptacle 40 for engagement with the leaf springs 56 of the terminal 46.
Referring to
The retention members 64 extend in a lengthwise direction to maintain contact with the receptacle housing 38 when in contact with the pin 76. The reaction force provided to the leaf springs 56 optimizes surface engagement with the pin 76 for enhancing the contact and consequently conductivity. Likewise, the retention members 64 are oriented generally cylindrically for optimizing overall contact of the terminal 46 with the receptacle housing 38 for enhancing contact surface area and consequently conductivity.
Each leaf spring 56 provides two contact points with the receptacle housing 38 when deformed by the pin 76—one contact point at the retention member 64 and another contact point at the body 48, or at a proximal end of the leaf spring 56. The two contact points create a dual electrical pass for current, thereby improving performance. The dual contacts increase a reaction force within the confines of the receptacle 40, which enhances the reliability of the connection for a compact connection.
The terminal 46 may be formed integrally from a single sheet of stamped spring tempered alloy or binary metal. The sheet of material may have a length from the proximate end 52 of the terminal body 48 to the distal end abutment surface 80 of the retention member 64. The distal end abutment surface 80 may be provided by a thickness of the sheet of material. The sheet of material may have a width terminating at lateral ends that are formed together to collectively provide the slit 50. The sheet of material may be rolled about a lengthwise or central axis of the terminal 46.
The terminal 46 may be utilized in the connector assemblies 28 for vehicle charging systems 22. Such systems often employ high-voltage charging, which is most effective if contact of electrical connections is optimized. Additionally, such vehicle charging systems 22 are exposed to harsh environments and undergo multiple mating cycles. The terminal 46 improves contact of the receptacle housing 38 with the terminal 46 as well as contact of the terminal 46 with the pin 76. These improved contacts improve the durability of the terminal 46 and consequently the durability of the receptacle housings 38 and the connector assembly 28.
Referring now to
Each terminal 84, 86 has a generally cylindrical body 88, 90 respectively. The body 88 of the first terminal 84 is inserted against the blind depth end 44. The body 90 of the second terminal 86 is inserted spaced apart from the body 88 of the first terminal 84 and is oriented near the opening 42 of the receptacle 40. A retainer 92 is provided with the body 93 having an abutment surface 96 against the body 90 of the terminal 86 thereby orienting the terminal 86 in a receptacle direction of the receptacle 40.
Each terminal 84, 86 has a radial array of leaf springs 94, 96 that are each spaced circumferentially apart with gaps 98, 100 between the corresponding leaf springs 94, 96. Each leaf spring 94, 96 has a first angled portion 102, 104 extending lengthwise from the body 88, 90 and extending centrally inward. Each leaf spring 94, 96 may also have a second angled portion 106, 108 that extends longitudinally away from the first angled portion 102, 104 and radially outward.
The terminals 84, 86 are axially aligned with the leaf springs 94, 96 oriented between the terminal bodies 88, 90. The leaf springs 94, 96 may overlap within a common region of the receptacle 40. For clearance, the leaf springs 94 of the first terminal 84 extending to the gaps 100 between the leaf springs 96 of the second terminal 86. Likewise, the leaf springs 96 of the second terminal 86 extend into the gaps 98 between the leaf springs 94 of the first terminal 84.
By utilizing two terminals 84, 86 within one receptacle 40, a large number of leaf springs 94, 96 may be employed thereby enhancing contact with the pin 76. Likewise, by employing a pair of terminals 84, 86 a pair of bodies 88, 90 are utilized for engaging the receptacle housing 38 thereby increasing contact between the terminals 84, 86 and the housing 38.
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.
