Blind mating connector having self-locating feature
BACKGROUND OF THE INVENTION 
     The present invention relates in general to a connector assembly for establishing a blind connection between an electrical device and a panel, and more specifically to a floating connector block contained in an aperture on a panel having a means for movably locating the floating connector block at the theoretical center of the aperture. 
     This application is related to copending application Ser. No. 161,067, filed Feb. 26, 1988, now abandoned entitled &#34;BLIND MATE SHIELDED INPUT/OUTPUT CONNECTOR ASSEMBLY&#34;, incorporated herein by reference. The prior application discloses a connector assembly useful in the robotic assembly of electrical components to an instrument panel or other panel in an automobile. A receptacle module is mounted in an aperture on a carrier panel so that the receptacle module can move in any direction within the plane of the panel. Flanges project from the receptacle module disposed on opposite sides of the carrier panel in order to retain the receptacle module within the aperture and to accept insertion and removal forces of connection. 
     The angular orientation of the receptacle module connector terminals substantially coincides with a direction perpendicular to the carrier panel. The panel must then be in reasonably precise relationship with the direction in which the electrical component is robotically inserted. However, it is sometimes difficult to accomplish such precise alignment in an automobile instrument panel or other panel. Also, the receptacle module tends to rest at the bottom of the aperture. Thus, even though the receptacle is free to move within the plane of the aperture, its length of travel in the downward vertical direction is depleted even before interconnection is attempted. Therefore, the acceptable error in initial alignment does not allow the inserted part to be lower than the receptacle. It would be desirable to increase the tolerable positional error to improve the manufacturability of instrument panels by robotics. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is a principal object of the present invention to provide an improved connector assembly in which the floating connector block is initially maintained at the approximate center of the carrier panel aperture. 
     It is another object of the present invention to provide an apparatus for mechanically and electrically connecting a device to a panel in which the axis of the floating connector block is initially substantially perpendicular to the panel and is rotatable therefrom. 
     It is a further object of the invention to provide a method for improved robotic installation of an electrical device to a carrier panel. 
     It is yet another object to provide a floating connector block movable and rotatable in any direction and/or plane. 
     These and other objects are achieved by means of an apparatus for mechanically and electrically connecting a device to a panel. The apparatus comprises a carrier panel having an aperture therein. A floating connector block is received in the aperture. The floating connector block includes a main body and at least two pairs of longitudinally spaced flanges extending from the main body in planes parallel with the plane of the aperture. The connector block is located within the aperture so that the carrier panel is disposed in the space between the flanges of each pair. The floating connector block further includes a plurality of terminals within the main body for establishing electrical connections. The terminals are substantially perpendicular to the flanges. A plurality of resilient support strips extend between the flanges of each of the pairs of flanges such that the strips are tensioned under contact with the carrier panel and tend to locate the floating connector block at a desired position within the aperture. The flanges are sufficiently spaced to allow a small amount of rotation of the floating connector block about any axis. A device-end connector is included on the component being connected to the panel and includes a plurality of pins arranged for matable connection to the block terminals. A guide means is provided on the floating block and the device-end connector for aligning the pins and the block terminals when the device-end connector and the floating connector block are brought together. Preferably, the resilient strips are comprised of elastomeric O-rings received in grooves on each respective pair of flanges. 
     The invention further provides a method for installing an electrical device to a carrier panel, comprising the steps of: (1) inserting the floating block into the aperture of the carrier panel such that the carrier panel is disposed between the flanges of each of the pairs of flanges and the resilient strips are tensioned under contact with the panel and the flanges; (2) orienting the device and the carrier panel such that the block terminals and the pins are substantially aligned; and (3) joining the device-end connector and the floating block by relative axial movement until the pins and the terminals are coupled. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, in which: 
     FIG. 1 is an exploded perspective view of a connector assembly according to the related application. 
     FIG. 2 is a perspective view showing connection of the connector assembly of the related application. 
     FIG. 3 is a cross-sectional view of the device-end connector and the floating connector block of the related application. 
     FIG. 4 is a perspective view showing the improved self-locating feature of the floating connector block of this invention. 
     FIG. 5 is a cross-sectional view taken between the O-ring and the main body of the floating connector block and looking away from the main body. 
     FIG. 6 is a cross-sectional view taken through the carrier panel. 
     FIG. 7 is a perspective view of a tray or chest-and-drawer type carrier panel for receiving the floating connector block and the electrical device to be connected thereto. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1-3 are illustrative of the connector assembly disclosed in application Ser. No. 161,067. 
     FIG. 1 illustrates an electrical device 10 which is desired to be interconnected with an instrument panel 11. A floating connector block 12 is suspended in an aperture 13 for interconnecting with a device-end connector 14. Floating block 12 includes an aperture 24 for receiving an electrical connector 15 which includes a plurality of terminal sockets 30 (FIG. 3) for connection to pins 16 of device-end connector 14. As shown in FIG. 3, male pins 16 are connected to circuit boards 27 and 28 in electrical device 10. Female terminals 30 are connected to individual lead wires 31 that together form a wire bundle. Alternatively, floating block 12 can be manufactured having electrical connectors embedded therein, rather than having a separate female connector block inserted into a receiving aperture 24. Furthermore, unique terminals can be provided in block 12, including terminals for coaxial wires or other shielded wiring. 
     Device-end connector 14 further includes a projection 17 having a beveled surface 18 for insertion into an aperture 19 in floating block 12 with a similar beveled surface (FIG. 3) for the purpose of guiding and aligning the insertion of pins 16 into connector terminals 30. A plurality of projection-aperture pairs may also be employed, if desired. Floating movement of floating block 12 is provided by means of a plurality of flanges including a first pair of flanges 20 and 21 and a second pair of flanges 22 and 23, each pair being spaced sufficiently to allow panel 11 to be disposed therebetween and to allow movement of block 12 in the plane of the panel. 
     As shown in FIG. 2, it is desired to insert an electrical device 10, such as for example, a radio, an instrument cluster, or a heater control unit, into an instrument panel having a front surface 25 and a rear panel 11. As device 10 is inserted through an aperture in front surface 25, the beveled surface 18 of projection 17 enters aperture 19 in floating block 12 in order to align pins 16 with female terminals 30 (FIG. 3). Female terminals 30 are connected to a wire bundle 26 that leads to other electrical devices in a vehicle. 
     As indicated in FIG. 2, floating block 12 is free to move within the plane of panel 11. However, this structure, as disclosed in U.S. application Ser. No. 161,067, is subject to the difficulty that prior to interconnection with device 10, floating block 12 is located at the lower extent of its travel in aperture 13 and further downward movement is not possible during interconnection. Therfore, any error in alignment which causes projection 17 to be lower than aperture 19 prevents proper connection of device 10 to block 12. 
     Although the spacing of flanges 20-21 and 22-23 is sufficient to provide limited lateral movement in any direction in the plane of panel 11, it is not sufficient to allow any rotation of floating block 12 outside of the plane of panel 11. Therefore, the successful interconnection of pins 16 and female terminals 30 is uncertain since the orientation of panel 11 and front face 25, as well as the control over the insertion path of device 10, are difficult to control within the tolerances of the floating connector. 
     FIG. 4 illustrates improvements according to the invention that solve the foregoing difficulties. Floating connector block 12 has a main body 35 and defines a longitudinal axis 38. Central aperture 19 extends in the direction of the defined longitudinal axis 38. Apertures 36 and 37 on either side of aperture 19 are adapted to receive female terminal connectors as described with reference to FIG. 1. Main body 35 has a lateral dimension d 1  and is adapted to be received in an aperture 13 formed in carrier panel 11. Aperture 13 has a lateral dimension d 3  which is greater than d 1 . 
     Carrier panel 11 has a thickness d 2 , at least in the vicinity of aperture 13. A pair of flanges 40 and 41 and a pair of flanges 42 and 43 extend from either side of main body 35 and are each spaced apart to receive carrier panel 11 therebetween. Each pair of flanges is spaced apart by a distance d 4  which is greater than carrier panel thickness d 2  by an amount sufficient to allow rotation of floating block 12 around any axis. Flanges 40 and 41 extend a distance d 5  from main body 35 and flanges 42 and 43 extend a distance d 6  from main body 35. The sum of d 1 , d 5  and d 6  is greater than d 3  so that the flanges provide stops for movement of main body 35 along longitudinal axis 38, thereby providing a means for accepting insertion and removal forces during interconnection and disconnection of the assembly. 
     Each flange has a height dimension d 8 . Respective upper and lower receiving grooves 50a and 50b, 51a and 51b, 52a and 52b, and 53a (and groove 53b, not shown) are formed in corresponding upper and lower edges of the flanges. A resilient component 44 formed of an elastomer material is disposed within receiving grooves 52a, 52b, 53a, and 53b of flanges 42 and 43. An identical component 45 is retained within grooves 50a, 50b, 51a, and 51b of flanges 40 and 41. In a preferred embodiment, resilient components 44 and 45 are comprised of O-rings which are self-retaining in the receiving grooves. Alternatively, components 44 and 45 may be formed by strips attached to and suspended between the flanges. 
     Aperture 13 includes a pair of upper tabs 55 and 56 separated by a distance d 7  which is less than d 3 , the upper surface of tabs 55 and 56 being sloped as shown. The edge of aperture 13 includes abutment surfaces 60 and 61 which are in contact with portions of O-ring 44, and abutment surfaces 62 and 63 which are in contact with portions of O-ring 45 when floating block 12 is inserted into aperture 13. The abutment surfaces are vertically spaced by a distance d 9  which is less than d 8  and is less than the vertical spacing of the upper and lower grooves in the flanges. The O-rings are tensioned under contact with the abutment surfaces such that floating block 12 is located at the theoretical center of aperture 13 while allowing movement of floating block 12 in the plane of panel 11 and allowing slight rotation about any axis. Aperture 13 also includes a pair of tongues 57 and 58 which provide a large contact surface between carrier panel 11 and flanges 40-43 during insertion and removal of device-end connector 14. The sloped upper surfaces of tabs 55 and 56 and tongues 57 and 58 allow for the installation of floating block 12 into aperture 13 with O-rings 44 and 45 already in place. Contact between O-rings 44 and 45 and tabs 55 and 56 retracts the O-rings during downward insertion of floating block 12 into aperture 13. 
     FIG. 5 is a sectional view of an O-ring as seen from the main body 35, showing the location of flanges 42 and 43 in a spaced relationship from panel 11. FIG. 6 shows O-ring 44 in contact with abutment surfaces 60 and 61, and O-ring 45 in contact with abutment surfaces 62 and 63. As a result, main body 35 is located at the theoretical center of the aperture. 
     It may be desirable to configure flanges 40-43 on floating block 12 in a staggered relationship so that the flanges on one side of block 12 do not overlap longitudinally. By keeping the flanges offset, floating block 12 can be formed by a simple injection molding process without the use of cams. Manufacture of block 12 can thus be made less expensive and time consuming. 
     An improvement of the blind mating capabilities of the invention is achieved using a tray 70 as shown in FIG. 7. A front face 71 includes screw holes 80-83 and locator holes 84 and 85 for attaching tray 70 to front face 25 of an instrument panel or other panel (see FIG. 2). A pair of side walls 73 and 74 extend back to carrier panel 11 with integrally molded springs 86 and 87 to center electrical device 10 in the left-right direction with aperture 13. A pair of ledges 75 and 76 extend along the bottom of side panels 73 and 74 and provide a sliding surface for the electrical device. A top extension 77 extends between the tops of side panels 73 and 74. 
     During insertion of electrical device 10, it is supported by ledges 75 and 76 and guided by side panels 73 and 74 and ledges 75 and 76 to more nearly align the connectors. Thus, a more reliable interconnection can be made using robotics. 
     To ensure that a device installed in tray 70 is retained there, a pair of retaining springs 78 and 79 extend from side panels 73 and 74, respectively. During insertion of the electrical device into the tray, springs 78 and 79 are compressed such that the device slides past. Upon full insertion of the device, springs 78 and 79 nest in receiving holes (not shown) provided in the sides of the electrical device. Alternatively, the springs can be attached to the sides of device 10 and receiving holes can be formed in side panels 73 and 74. 
     It can thus be seen that the present invention has achieved the objects as previously set forth. Using the described connector, electrical devices can be installed to an instrument panel or other panels at high efficiency and with low cost and a low failure rate. 
     While preferred embodiments of the invention have been shown and described herein, it will be understood that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will occur to those skilled in the art without departing from the spirit of the invention. Accordingly, it is intended that the appended claims cover all such variations as fall within the spirit and scope of the invention.