The present invention generally relates to electrical power connectors that are useful as low-profile board-to-board connectors and wire-to-board connectors and that can provide excellent operation under high current density conditions and are particularly suitable for use as modular components within modular assemblies.
It is desired to improve power connectors such as by reducing the size of the connectors and the space they take when connected, for example, to the surface of a board component such as to a printed circuit board (PCB). Increasing current density can contribute to reducing the size of a power connector, but heat generated by the Joule effect can have negative effects. The heat can cause a temperature rise of the contacts that adversely affects electrical characteristics and expands the contacts. With temperature cycling over time, the expansion effects can lead to loosened contacts or other metal components such as connector screws. There is an overall need to improve power connectors by decreasing size without requiring power reduction while addressing undesired temperature affects.
Prior art approaches include U.S. Pat. No. 4,845,589, which relates to bus bar connectors and addresses undesired effects due to temperature cycling owing to heat generation. The patent describes an electrical power connector having two exposed sidewalls that merge with a support structure to form a U-shaped structure. Extending from the two exposed sidewalls are spring contact arms that mate with a bus bar. A sliding structure is provided with the objectives of allowing easy access to the power connector and correcting problems resulting from temperature cycling. U.S. Pat. No. 5,618,187 pertains to a bus bar contact for mounting on a circuit board comprising a U-shaped center section, contact fingers, termination posts and stabilizing tabs. The U-shaped center section of the bus bar contact has two exposed parallel panels. U.S. Pat. No. 6,666,698 describes air gaps between terminals that are susceptible to arcing. The patent describes mechanical means which is said to impart higher mating and unmating velocities to diminish arcing in high volt systems. U.S. Pat. No. 6,930,889 relates to a circuit board and a slot connector assembly. The patent describes a circuit board comprised of a substrate and electrical contacts wherein the electrical contacts mate with contact springs of a slot connector.
Other prior art includes the following. U.S. Pat. No. 6,319,075 pertains to electrical connectors and more particularly to electrical power connectors said to be useful in circuit board or backplane interconnection systems. This patent describes electrical terminals comprising a pair of spaced apart planar walls having a bridging structure extending between and joining the walls. The bridging structure has forward and rearward bridging elements or a bridging element having an open upper section for heat dissipation. U.S. Pat. No. 6,780,027 relates to electrical connectors for transmitting electrical power. This patent is directed to an electrical connector having both an aperture for engagement with a complementary contact and a protruding tab for engagement with an AC cable plug. U.S. Pat. No. 6,848,950 is directed to power contacts employed in electrical connectors that transmit electrical power. The patent describes two-piece electrical contacts having three electrical interfaces. One electrical interface uses the walls of the two pieces to mate with an electrical connector; another interface has terminals or tails extending from the contact to engage a circuit board; and a third interface is a plug projection for engaging a cable plug. The patent further describes an electrical connector comprising a first power contact providing both a cable-to-board interface and a board-to-board interface. This patent also describes an electrical connector having a power contact with a first wall and a second wall wherein the first wall and the second wall are coupled. The electrical connector also has a second power contact with a third wall and a fourth wall wherein the third wall and the fourth wall are uncoupled. U.S. Pat. No. 6,848,953 describes an electrical connector, particularly electrical power connectors said to be useful in circuit board or backplane interconnectors. The patent discusses a contact with two opposing sidewalls having a bridge extending between the sidewalls and a clip extending from the bridge for engaging the arm of a bus bar.
The following patents describe other prior art proposals. U.S. Pat. No. 6,869,294 pertains to matable electrical connectors having power capabilities. The patent discloses a plug connector having a substantially U-shaped electrically conductive body. Three open sides and three closed sides define the body. The three closed sides comprise two side walls and an upper bridging element. U.S. Pat. No. 6,890,221 pertains to a matable electrical connector in a housing. This approach requires a receptacle connector comprising a pair of spaced receptacle contact walls and a plug connector comprised of a pair of spaced plug contact walls wherein both the receptacle connector and the plug connector are in the same housing. U.S. Pat. No. 7,059,919 pertains to an electrical connector, particularly electrical power connectors said to be useful in circuit board or backplane interconnectors. The patent discusses a pair of flexible beams that extend from a pair of opposed contact side walls. The flexible beams are widthwise tapered in a direction from which the beams extend. The flexible beams also extend outwardly away from each other and inwardly towards each other. An unobstructed heat flow path is defined between the flexible beams. U.S. Pat. No. 7,070,464 pertains to electrical connectors, particularly electrical power connectors said to be useful in circuit board or backplane interconnectors. The patent describes a pair of opposed contact walls having a bridging element adjoining the opposed contact walls. The patent discusses two opposed contact walls each having panels and flexible beams extending from the panels. The flexible beams extend outwardly away from each other and inwardly toward each other.
Prior art including some of that discussed hereinabove describes power connectors that use coupled contacts wherein a cumbersome and restrictive bridging element connects two contacts. The bridging elements take up space, restrict air flow and hinder flexible use of contacts. The power connector of this invention employing uncoupled contacts has a low profile but sufficient height to provide good air flow within the connectors. The power connectors as described herein have low profiles with only slight or moderate temperature rise during extended use. Advantageously, board space is saved, the power connectors providing about 30 to about 60 amps per blade and typically about 45 to about 55 amps per blade, equating to between about 120 and about 300 amps per inch and typically between about 180 and about 275 amps per inch.
With the present approach, it has been determined that various characteristics of prior art such as these patents may have shortcomings such as these and undesirable attributes, results or effects. The present approach recognizes and addresses matters such as these to provide enhancements not heretofore available. Overall, the present approach more fully meets the persistent need for smaller power connectors to accommodate more power with limited temperature rise and limited space requirements.
One aspect or embodiment of the invention relates to improved power connectors that have an insulative housing. These housed power connectors have improved and lower. profiles, typically 30% less than commercial housed power connectors with similar power performance. The improved power connectors can include plug connectors and receptacle connectors for mating with each other or other components. The power connector, the receptacle connector or both may comprise two uncoupled contacts seated in cavities in the housing. The contacts have exposed surfaces to dissipate heat resulting from Joule effects, and the cavities are constructed with openings and/or spacings to improve air flow in one or more of the top, bottom, bottom and/or rear of the connector cavities. Improved airflow permits higher current density without unacceptable temperature rise and contributes to providing power connectors that have a low profile with no sacrifice of quality or power handling capabilities.
In another aspect or embodiment, the use of uncoupled walls eliminates a bridging structure that is used in some prior art approaches to couple and hold two contact walls in position relative to one another. The bridging structure typically needs space on the topside of the contact walls adding to the connector height and profile. Eliminating the space required when a bridging structure is included contributes to a lower connector profile.
According to another aspect or embodiment, the uncoupled contacts can employ small barbs on the sides of the contacts to assist in holding the contacts in place. According to one approach, a barb is positioned on a side, such as near the bottom of a contact to ride on a shoulder of the housing and lock in the contact vertically. According to another approach, a barb near the top of a contact locks the contact into a housing channel to lock in the contact horizontally. Each barb adds little if anything to connector profile. Typically both barb arrangements will be used to provide secure positioning in two dimensions.
According to a further aspect or embodiment, the mating sections of the contacts for the plug connector form a blade structure, and the mating sections of the contacts for the receptacle connector typically have multiple contact beams for parallel path current flow to minimize resistance and heat generation in order to aid in employing higher current densities. The multiple contact beams form a receiving section that has camming portions for blade entrance and restriction portions for tight blade contact.
In accordance with another aspect or embodiment, and for ease of mating and facilitating of modular assemblies, one mating connector can have guide posts and the other mating connector can have guide apertures to receive the guide posts. The guide posts and apertures can be placed on top of the connectors which typically preserves board space or can be placed the side of the connectors for enhanced air flow.
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, which may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriate manner.
Also extending from back panels or body panels 18 and 20 are beams 42 and 44, respectively. In some embodiments, such as shown in
Whether the tails are oriented generally orthogonal or generally in line with the beams and blade formed therefrom, the blade extends from back panel or body panel pairs or contact members 18, 20 or 18a, 20a. Viewed in the direction out of the plug connector, and toward the receptacle connector (or outwardly), beams 42 and 44 extend from the back or body panels first in an inward direction toward each other until they meet, and then they are parallel to each other, typically in contact with each other along this length. The outwardly extending section of the beams 42 and 44 form blade 46, which is the mating portion of the contacts 13 of the plug connector 10. As seen in
Receptacle connector, generally designated at 11 in
In some embodiments, such as shown in
Whether the tails are oriented generally orthogonal or generally in line with the beams, the beams extend from the back panels or body panels 54, 56. When considering the combination of plug connector and receptor connector, and viewed in the direction out of the receptacle connector 11 and toward the plug connector 10 (or inwardly), beams 76, 78 and 80 and beams 82, 84 and 86 first extend from the respective panels 54 and 56 inwardly toward the opposing beam of the opposing contact and then outwardly away from the opposing beam. The sections of the opposing beams that extend outwardly form camming surfaces 88 and 90 first contact a plug connector during mating. In an illustrated embodiment, the camming surfaces 88, 90 engage blade 46 of the plug connector 10. Proper mating action proceeds, with the camming surfaces helping to guide blade 46 to enter receptacle connector 11. Thereafter, the blade 46 encounters restriction portions 92 and 94 of beams 80 and 86, respectively. Substantially simultaneously, like restriction portions of beams 76, 78 and 82, 84 respectively are encountered by the blade 46. This mating typically is completed when opposing surfaces of the plug connector 10 and receptacle connector 11 contact each other to stop any further movement of the plug connector and/or receptacle connector toward each other.
Referring to
This illustrated plug connector embodiment also provides a barb or a projecting member 120 on each or both of contact members 14 and 15, as shown for example in
Referring to
This illustrated receptacle connector embodiment also provides a barb 138 in one or each of contact members 48 and 50 that fits within housing channel 134 at each section to prevent horizontal movement of contact members 48 and 50 within housing 122, while providing air space around the contact members 48 and 50. When tails are soldered in place, the contact barbs, the housing shoulders and the housing channels can be positioned such that housing 122 is positioned slightly above the PCB 148 so there exists a slight space between housing 122 and the PCB.
Referring to
As seen in
Electrical current flows through a plug connector 10 and/or a receptacle connector 11 when it is put into use, typically as mated together, heat is generated due to the Joule effect. The generated heat, if not dissipated, can cause temperature rise and limit current flow because only limited temperature rise can be tolerated. A cross flow of air over the exposed surfaces of the contact members 14 and 15 and/or 48 and 50 for example will dissipate the generated heat and limit temperature rise. Air can enter the cavities 98 and/or 130 through their rear openings and pass over the contacts such as 14, 15 and/or 48 and 50. Air also will exit from rear openings of the cavities 98 and/or 130. In addition, some air will escape from the apertures 112 and/or 114 in the top and bottom walls of the plug cavities thus dissipating heat. When assembled onto a board component such as a PCB, a slight airspace or clearance between contacts 14 and 15 and/or 48 and 50 and the PCB to which they are connected and a slight airspace or clearance between housing 96 and/or housing 122 and the PCB to which they are connected can aid in improving airflow. Heat dissipation is further realized by the uncoupled contact member pairs that are provided by the present structure, especially when the uncoupled characteristic is combined with open volumes that are provided on the faces of the contact members that are opposite of the opposing uncoupled faces of those same contact members that define the medial space. In this way, each contact member face is directly engaged by minimal solid matter, leaving additional open air volume for heat dissipation.
In an embodiment,
DC power input of power receptacle module 221 as shown in
Signal module 223 has insulative housing 164 and suitably contains between about 6 and about 40 mated signal contacts and typically between about 18 and about 32 signal receptacle contacts 166. Side 170 of signal receptacle housing 164 interconnects to side 172 of power input receptacle housing 208, as shown in
DC ground return receptacle module 225 (
As shown in
Guide posts 264 and 266 (
In another aspect or embodiment, modular connector system 210 shown in
It will be understood that there are numerous modifications of the illustrated embodiments described above which will be readily apparent to one skilled in the art, such as many variations and modifications of the power connector and/or its components including combinations of features disclosed herein that are individually disclosed or claimed herein, explicitly including additional combinations of such features, or alternatively other types of power connectors. Also, there are many possible variations in the materials and configurations. These modifications and/or combinations fall within the art to which this invention relates and are intended to be within the scope of the claims which follow.