Abstract:
A connector system. In one embodiment, the connector system includes a receptacle housing with a plurality of receptacle electrical contacts fixedly attached thereto, and a plug housing comprising a plurality of plug electrical contacts fixedly attached thereto. Each of the plug electrical contacts comprises a proximal end that includes a blade in a first plane. The proximal end is connectable to a first electronic component. Each of the plug electrical contacts further comprises a distal end that includes a blade substantially in a second plane that is orthogonal to the first plane. When the plug housing is inserted in the receptacle housing, the distal end is in contact with a respective one of the plug electrical contacts, and the plug housing and the receptacle housing are rotatable with respect to each other in the second plane.

Description:
RELATED APPLICATION 
     This patent application claims priority from United States Provisional Patent Application No. 60/203,806, filed May 12, 2000. 
    
    
     FIELD OF INVENTION 
     This invention generally relates to electrical connector systems with plugs and receptacles. 
     BACKGROUND OF THE INVENTION 
     Many electrical devices must be easily connected to and disconnected from another device that serves as an electrical signal source or sink for the device. For example, many hand-held devices such as personal data assistants (PDAs) and global positioning system (GPS) devices must be repeatedly connected to and disconnected from mating devices. The mating devices may charge the power supply of the hand-held device or transfer data to and from the hand-held device. A common example is a PDA and its cradle. The PDA functions independently, but can be placed in the cradle to make electrical connections through which the PDA communicates with a computer or some other device. Conventional connector systems have disadvantages in such applications. For example, parts of either the hand-held device or the mating device may be broken in use. 
     The electrical connectors in the hand-held device must be easily aligned with the electrical connectors in the mating device so that a user can quickly and frequently place the hand-held device properly in the mating device. One conventional solution is to include alignment pins on one or both of the handle-device and the mating device. The alignment pins or even the electrical contacts are often broken off, however, because the user fails to pull the hand-held device out of the mating device in a direction parallel to the alignment pins and mating contacts. Alignment pins or electrical contacts may also be broken during placement of the hand-held device in the mating device. 
     Conventional approaches to connectors include “floating” connectors. For example, electrical panels in “drawers” may be installed into a rack that includes a guiding mechanism and a mechanism that allows the device to float relative to the mated connectors. Floating connectors are limited, however, because the allowed movement is restricted to movement of the mated connectors in a plane of the installed panel. When the drawer is installed, connectors in the drawer mate with connectors in the rack in a plane. In the conventional drawer connector system, movement of the drawer connectors with respect to the rack connectors, or pivoting of one of the connectors outside of the plane while maintaining the electrical connection with the other connector, is not allowed. 
     SUMMARY OF THE DISCLOSURE 
     A connector system with a plug and a socket is described. The connector system allows rotation of the plug and the socket with respect to each other while the plug and the socket are electrically coupled. Embodiments of the connector system help to prevent component and connector damage during coupling and uncoupling of mating components. In one embodiment, the connector system includes a receptacle housing with a plurality of receptacle electrical contacts fixedly attached thereto, and a plug housing comprising a plurality of plug electrical contacts fixedly attached thereto. Each of the plug electrical contacts comprises a proximal end that includes a blade in a first plane. The proximal end is connectable to a first electronic component. Each of the plug electrical contacts further comprises a distal end that includes a blade substantially in a second plane that is orthogonal to the first plane. When the plug housing is inserted in the receptacle housing, the distal end is in contact with a respective one of the plug electrical contacts, and the plug housing and the receptacle housing are rotatable with respect to each other in the second plane. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective cutaway view of one embodiment of a rotatable connector system. 
     FIG. 2A is a diagram of an embodiment of a plug electrical contact. 
     FIG. 2B is a diagram of different view of the plug electrical contact of FIG.  2 A. 
     FIG. 3 is a diagram of an embodiment of a plug electrical contact in the mated position with respect to an embodiment of a receptacle electrical contact. 
     FIG. 4 is a perspective view of an embodiment of a rotatable connector system installed in a hand-held device and mating cradle. 
     FIG. 5 is a perspective view of the hand-held device and mating cradle of FIG. 4 in a rotated position. 
     FIG. 6 is a diagram of a receptacle of an embodiment installed in hand-held device. 
     FIG. 7A is a diagram of one embodiment of a plug and receptacle. 
     FIG. 7B is a diagram showing another view of the plug and receptacle of FIG.  7 A. 
    
    
     DETAILED DESCRIPTION 
     A connector system with a plug and socket is described. The connector system allows rotation of the plug and socket with respect to each other while the plug and socket are electrically coupled. Embodiments of the connector system help to prevent component and connector damage during coupling and uncoupling of mating components. FIG. 1 is a diagram of an embodiment of a connector system  100 . The connector system  100  includes a plug housing  102  and a receptacle housing  112 . Portions of the plug housing  102  and the receptacle housing  112  are cut away to show contacts  108  and  110 . Reference number  110  indicates a representative receptacle electrical contact. The receptacle electrical contact  110  is fixedly attached to the receptacle housing  112 . The receptacle electrical contact  110  is a single piece of conductive material in a blade shape with a ninety degree angle between its two ends. One end of the receptacle electrical contact  110  is a mating end that is accessible through an opening in the receptacle housing  112 . As shown in FIG. 1, all of the mating ends of the receptacle electrical contacts  110  are accessible through a single opening in the receptacle housing  112  that faces the plug housing  102 . The ends of the receptacle electrical contacts  110  opposite the mating ends may be electrically connected to an electrical component either removably or permanently. 
     The plug housing  102  includes two bosses  104  that allow the plug housing  102  to be connected to a component, for example by screws inserted through the holes in the bosses  104 . The plug housing  102  further includes two tapered ears  115  that fit into the opening in the receptacle housing  112 . Between tapered ears  115 , multiple guide openings  113  in the plug housing  102  each accept one mating end of a receptacle electrical contact  110 . Each plug electrical contact  108  includes a distal end accessible through the guide opening  113  and a proximal end that projects between the bosses  104 . Each plug electrical contact  108  is fixedly attached to the plug housing  102  between its distal end and its proximal end. The proximal ends of the plug electrical contacts  108  may be electrically connected, removably or permanently, to an electrical component. The proximal ends of the plug electrical contacts  108  are blades in one plane. The distal ends of the plug electrical contacts  108  are the distal sections of the same blades bent to be substantially in a plane orthogonal to the plane of the proximal ends. When the plug housing  102  is inserted in the receptacle housing  112 , the mating end of a receptacle electrical contact  110  is placed in physical contact with a distal end of a respective plug electrical contact  108 . The plug housing  102  and the receptacle housing  112  are rotatable with respect to each other while the electrical connection between the plug electrical contacts  108  and the receptacle electrical contacts  110  is maintained. The limits of rotation are defined by the ears  115  making contact with sides of the opening in the receptacle housing  112  in which the ears  115  are inserted. In one embodiment, the plug housing  102  and the receptacle housing  112  may rotate through an angle of up to thirty degrees with respect to each other. 
     In various embodiments, the number of plug electrical contacts  108  and the number of receptacle electrical contacts  110  varies according to need. For example, one embodiment has four plug electrical contacts  108  and the same number of receptacle electrical contacts  110 . Another embodiment has twenty plug electrical contacts  108  and the same number of receptacle electrical contacts  110 . In general, according to the components that are to be electrically coupled through the connector system  100 , the number of plug and receptacle contact pairs may vary between one and twenty or more pairs of contacts. 
     In one embodiment, the plug housing  102  and the receptacle housing  112  are made of glass reinforced thermoplastic. In various embodiments, the plug housing  102  and the receptacle housing  112  may be made of any relatively rigid insulating material with the appropriate wear characteristics. In one embodiment, the receptacle electrical contacts  110  and the plug electrical contacts  108  are made of a copper alloy plated with gold. The receptacle electrical contacts  110  and the plug electrical contacts  108  may be made of any conducting material with the appropriate electrical and mechanical characteristics for the required application. The material should be resilient such that the distal ends of the plug electrical contacts retain resilience after being preshaped as shown in FIG.  2 A. 
     FIG. 2A is a diagram of a plug electrical contact  108 , showing the distal end  111  and the proximal end  109 . In one embodiment, the plug electrical contact  108  is a single piece of a resilient, conductive material. The distal end  111  is preshaped so as to remain biased against the mating end of a respective receptacle electrical contact  110 . FIG. 2B is a right side view of the plug electrical contact  108  of FIG. 2A, and FIG. 2C is a left side view of the plug electrical contact  108  of FIG.  2 A. 
     FIG. 3 is a diagram of a plug electrical contact  108  in a mated position with a receptacle electrical contact  110 . The area  220  is the area of electrical contact and the point about which the plug electrical contact  108  and the receptacle electrical contact  110  rotate with respect to each other. 
     FIG. 4 is a diagram of one embodiment in which the connector system  100  is used to couple a hand-held device  202  and a cradle  204 . The cradle  204  may be a source of power for recharging or may facilitate communication between the hand-held device  202  and, for example, a personal computer. The hand-held device may be any hand-held electrical component, such as a personal data assistant (PDA), that must occasionally communicate with another electrical component. The hand-held device  202  rests in the cradle in a curved rest area  208 . The hand-held device includes a curved area  206  that fits into the curved rest area  208  and allows easy rotation of the hand-held device  202  with respect to the cradle  204 . When the hand-held device  202  is placed in the cradle  204  or removed from the cradle  204 , the natural path of motion is not straight into and out of the cradle  204  in line with the contacts  108  and  110  of the plug housing  102  and the receptacle housing  112 . Rather, the natural path includes placing lateral stress on the connector  100 . For example, a user removing the hand-held device  202  from the cradle  204  naturally pulls the hand-held device out from the cradle  204  either before or at the same time the user pulls the hand-held device  202  up in line with the connector  100 . The connector  100  allows rotation of the plug housing  102  and its contacts  108  with respect to the receptacle housing  112  and its contacts  110 . Connector system  100  thus alleviates the problem of inadvertent component and contact damage on insertion and removal of the hand-held device  202 . 
     The plug housing  102  is shown connected to the cradle  204  by screws  210  through the bosses  104 . The proximal ends of the plug electrical contacts  108  are visible inside and outside the plug housing  102  in this case because the plug housing  102  is made of a transparent insulator material. In other embodiments, the plug housing  102  may not be transparent, in which case only the tips of the proximal ends of the plug electrical contacts  108  extending beyond the plug housing  102  would be visible. A connector (not shown) may be removably coupled to the proximal ends of the plug electrical contacts  108  to couple the connector  100  directly or indirectly to some device, such as a personal computer. In other embodiments, the plug electrical contacts  108  may be permanently coupled to another connector or to a device or component, for example by soldering the proximal ends. 
     FIG. 5 is a diagram of the hand-held device  202  coupled to the cradle  204  through the connector  100 . In this diagram, the hand-held device  202  is rotated through an angle  302  with respect to the cradle  204 . In one embodiment, the angle  302  represents one half of the total rotation possible. In various embodiments, the total angle of rotation available may be variously distributed between a direction to one side of the connector  100  and a direction to the opposite side of the connector  100 . For example, in some embodiments, the cradle  204  may hold the plug connector  102  in a vertical position and allow rotation out of the vertical in two directions. In one embodiment, the total angle of rotation is less than or equal to thirty degrees. 
     FIG. 6 is a diagram showing the side of the hand-held device  202  that faces the cradle  204  (and is therefore not visible in FIGS.  4  and  5 ). The hand-held device  202  includes a circuit board  402  containing electrical components necessary to make it function. Part of the circuit board  402  is visible because a region of the hand-held device  202  casing is cut away, as shown. The receptacle housing  112  is shown. The receptacle housing  112  appears as it would if it were made of a transparent insulating material so that all of the mating ends of the receptacle electrical connections are visible. The ends opposite the mating ends (not shown) are inserted into the circuit board  402  and are permanently coupled to electrical contacts on the side of the circuit board  402  that is not shown. For example, each of the receptacle electrical contacts  110  may be soldered, in which case, solder dots such as solder dots  406  would be visible on the circuit board  402 . 
     In one embodiment of the connector system  100  suitable for a common PDA device and cradle, the connector system has a current rating of one amp, a dielectric withstanding voltage of 400 volt alternating current, and an insulation resistance of 1000 megaohms. Typical mechanical characteristics of such an embodiment include a 5000 cycle life, a contact normal force of 3.5 pounds, a withdrawal force of 0.7 pounds, minimum, and an operating temperature range of from −10° C. to +105° C. 
     FIG. 7A is a diagram of one embodiment of a connector system having ten sets of plug electrical contacts  1087  and receptacle electrical contacts  1107 . A plug housing  1027  is shown with its dimensions, and a receptacle housing  1127  is shown with its dimensions. FIG. 7B is a diagram showing a side view of the plug housing  1027  with its dimensions, and a side view of the receptacle housing  1127  with its dimensions. 
     The invention has been described with reference to specific embodiments. Various modifications may be made by one of ordinary skill in the art without departing from the spirit and scope of the invention as defined in the following claims. For example, alternative materials, different dimensions, and different configurations are within the scope of the invention as claimed. In addition, the connector system described may used to electrically couple, directly or indirectly, any components other than the components specifically shown and described.