Abstract:
A connector setup is disclosed where one connector can be blind mated to another connector. In a fixed panel, a connector is spring mounted upon the fixed panel such that the connector has freedom of movement in all directions. In addition, the springs are configured so as to provide enough force to mate the connector with a mating connector. Either connector can be mounted between guide pins. The corresponding connector would then be mounted between guide holes. When the module upon which one of the connectors is mounted is slid into the fixed panel, the guide pins interact with the guide holes so as to properly position the connectors in relation to each other. The springs, in addition to providing enough force to mate the connectors, also allows the connector on the panel to float within its mount, permitting the connector to be optimally positioned for mating purposes.

Description:
BACKGROUND  
         [0001]    1. Technical Field  
           [0002]    The present invention is related to the interconnection of electronic devices. More particularly, this invention is related to a mounting scheme that allows the blind mating of electrical connectors in a tray to electrical connectors in a module that is inserted into the tray.  
           [0003]    2. Background Information  
           [0004]    Electrical connectors are used to interconnect electrical devices. There are many different types of electrical connectors in use today. For example, D-sub connectors are well-known in the part: they are very common, for example, in personal computers. A typical personal computer system contains several D-sub connectors, including serial ports, parallel printer ports, connections for a monitor, and game ports.  
           [0005]    The operation of prior art D-sub connectors is shown in FIG. 1. FIG. 1 shows an exemplary pair of D-sub connectors that mate with each other. Female connector  100  is a connector with fifteen holes  102 . Each hole  102  may be connected to a lead to transmit and receive signals. Flange  104  surrounds the holes. Male connector  110  is a connector has fifteen pins  112 . It should be understood that female connector  100  need not have fifteen holes and male connector need not have fifteen pins. D-sub connectors are available with a wide range in the number of holes and pins available: 9-pin connectors and 25-pin connectors are also common. Each hole  102  may be connected to a lead to transmit and receive signals. Flange  114  surrounds the pins.  
           [0006]    To establish a connection between female connector  100  and male connector  110 , one typically places flange  114  of male connector  110  such that it surrounds flange  104  of female connector  100  so that pins  112  are aligned with holes  102 . When male connector  110  is coupled to female connector  100 , several lines of communication will be established through a single connector. Typically, screws  116  and  118  may be provided in proximity with male connector  110  (e.g., within approximately 1 cm) such that screws  116  and  118  fit into nuts  106  and  108 , which are in proximity with female connector  100 . Screws  116  and  118  can be secured with nuts  106  and  108  so as to prevent an accidental disconnection.  
           [0007]    Typically, after a user connects the D-sub connectors together, one can tighten the connection using screws. This tightening ensures that the connection is secure and the connection will not terminate inadvertently.  
           [0008]    In certain situations, however, one is not able to manually secure such a connection. For example, certain aircraft systems, such as avionics and communications hardware, may be placed in modules that are inserted into trays contained that are located inside panels located in various areas of the aircraft, including the cockpit. The construction of these modules usually places connectors at the rear of the modules. The corresponding connectors are located at the rear of the tray in a wiring harness. Because of the placement of these connectors, access to the connectors may be restricted.  
           [0009]    In an aircraft, modules are typically inserted into trays that are fixed in the cockpit and various other areas of the aircraft. FIG. 2 illustrates an exemplary tray  200  into which a module is inserted. Tray  200  includes rear plate  210 . Attached to rear plate  210  is connector  212 . It should be noted that a rear plate may contain a plurality of connectors. To simplify the illustration of the tray, however, only one connector has been illustrated in FIG. 2.  
           [0010]    Referring now to FIG. 3, module  300  is illustrated as containing a display  302 . It should be understood, however, that there are many different types of modules with many different types of functions available. The modules typically contain one or more connectors located at the rear of the modules, such as connector  304 . Connector  304  connects with connector  212 , located on rear plate  210  of tray  200 . In order to couple connector  304  with connector  212 , module  300  is inserted into tray  200 .  
           [0011]    One prior art method of inserting a module into a tray is as follows. A technician pulls a portion of the wiring harness out with the module and manually connects and secures the cables to the module. Thereafter, the module would be inserted into the tray. This can be a tedious process that may lead to several problems. For example, in pulling out the wiring harness to make the connection and inserting the module into the tray, it is possible to bend or break the cables. In addition, if the wiring harness is not correctly placed back into the tray, the module may not insert fully into the tray. Furthermore, the designers of the trays would have to provide room behind the tray for the slack of the wire to be stored when the module is fully inserted.  
           [0012]    Because of the location of the connectors, it is impractical to visually align module  300  with tray  200  while inserting the module. It is therefore desirable to provide a device and technique to align the connectors blindly.  
           [0013]    One prior art device for implementing a blind-mating technique is illustrated in FIG. 4A. Similar to the connectors of FIG. 1, connector  400  contains a flange and a plurality of pins. Corresponding connector  402  also contains a flange and several holes. In order to allow a user to connect the module with the tray without manually manipulating the connectors, connector  402  contains guide pins  410  and  412 . The corresponding connector contains through holes  414  and  416  that align with guide pins  410  and  412 , respectively. The guide pins may or may not be tapered such that the end that first comes into contact with the through holes is the narrowest portion and the pin is thicker closer to connector  402 . As guide pins  410  and  412  first contact through holes  414  and  416 , the connectors start to become aligned with each other. As the connectors are pushed towards each other, the thicker portion of the guide pins is in contact with through holes  414  and  416 . The thicker portion of the guide pins has less freedom of movement within through holes  414  and  416 . Thus, there is a closer alignment between the connectors before the respective flanges interconnect.  
           [0014]    Connector  400  of FIG. 2 may be rigidly attached to the tray. Thus, connector  402  must move to the position of the connector  400  in order for the connection to occur. Because connector  402  is rigidly attached to the module, the entire module must be moved in order for the connectors to be aligned. Because of manufacturing inefficiencies, there are instances in which such an alignment is not possible.  
           [0015]    Float bushings  420  may also be added to connector  400 . Float bushings  420  allow connector  400  to move or “float” within certain limits. Thus, the addition of float bushings adds tolerances to the connector system. Instead of only moving connector  410  to align with connector  400  as with the system without the float bushings, both connectors  400  and  410  move with respect to each other to establish a connection.  
           [0016]    While the addition of float bushings  420  allows movement in two mutually perpendicular directions, there is no provision for movement in the front-back direction, the direction of the insertion of the module. This can lead to some problems with misalignment. Because of manufacturing tolerances, the front-back dimension of the modules are not always the same. Therefore, when a module is inserted into a tray, there may be a portion of the front of the module (the “bezel”) that protrudes from the face of the tray. Furthermore, there may be a situation where the module, when inserted fully into the tray, is not as long as required. Therefore, the connectors may not fully engage with each other and are more easily disconnected from one another due to vibrations, movement, accidental bumping, etc.  
           [0017]    In addition, the use of float bushings may result in a connector that is no longer centered within its mounting holes. Because a typical tray and module are mounted such that the connectors are vertically oriented, the float bushings tend to settle at the bottom of the hole in which it is mounted.  
           [0018]    With reference to FIG. 4B, float bushing  450  rests within mounting hole  452 . A connector would be mounted by a bolt through the center of float bushing  450 . It is evident that the float bushing configuration is merely the placement of a bushing in a mounting hole that is larger than the float bushing. The float bushing thus has the capability to move throughout the mounting hole. However, because of gravity, float bushing  450  rests at the bottom of mounting hole  452 . The result of this phenomenon is that there is no freedom of movement towards the bottom of mounting hole  452 . Thus, when guide pins  410  and  412  are inserted into guide holes  414  and  416 , the freedom of movement of connector  420  is limited.  
           [0019]    For the foregoing reasons, there is a need for a connector setup that allows users to insert a module into a tray without having to manually connect the cables. There is also a need for a connector setup in which there is no need to pull the wiring harness out of the tray to establish a connection.  
         SUMMARY  
         [0020]    The present invention is directed to an apparatus that satisfies those and other needs. An apparatus having features of the present invention includes a tray containing a rear hole. There is also a fastener mounted in the rear hole with a spring mounted on the fastener. A mounting plate is further attached to a connector and the mounting plate is mounted on the fastener and the spring.  
           [0021]    The fastener may be set up such that the fastener floats within the rear hole by having a fastener which is smaller than the rear hole.  
           [0022]    There may also be a guide pin located on the rear plate.  
           [0023]    A module having features of the present invention for insertion into the tray contains a connector and a guide hole located in proximity to the connector. Ideally, the guide hole is configured such that the insertion of the module into the tray results in the guide hole interfacing with the guide pin.  
           [0024]    An alternative embodiment of the present invention contains guide pins on the module. Then the tray contains mounting holes located on the mounting plate. Therefore, the guide pins on the connector of the module interface with the guide holes on the connector of the tray.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]    The features, aspects, and advantages of an embodiment of the present invention will become better understood with reference to the following description, appended claims, and drawings, where like reference numbers depict like elements, in which:  
         [0026]    [0026]FIG. 1 depicts a pair of D-sub connectors;  
         [0027]    [0027]FIG. 2 illustrates an exemplary tray and the placement of the connectors on the tray;  
         [0028]    [0028]FIG. 3 shows an exemplary module for insertion into the tray of FIG. 2;  
         [0029]    [0029]FIGS. 4A and 4B depict an exemplary blind-mating system;  
         [0030]    [0030]FIGS. 5A and 5B depict a rear plate located at the rear of a tray, upon which connectors can be mounted;  
         [0031]    [0031]FIG. 6 shows a portion the rear of a module containing the connectors that couple with the connectors shown in FIGS. 5A and 5B; and  
         [0032]    [0032]FIG. 7 shows an alternative embodiment of the connector setup system. 
     
    
     DETAILED DESCRIPTION  
       [0033]    The novel features of the present invention will become apparent to those of skill in the art upon examination of the following detailed description of the invention or can be learned by practice of the present invention. It should be understood, however, that the detailed description of the invention and the specific examples presented herein, while indicating certain embodiments of the present invention, are provided for illustration purposes only, because various changes and modifications that are within the scope of the invention will become apparent to those of skill in the art from the detailed description of the invention and claims that follow.  
         [0034]    [0034]FIG. 5A shows a side view of an exemplary rear plate of a tray containing an exemplary embodiment of the present invention. Connector  500  is attached to a mounting plate  502 . Connector  500  may be a D-sub connector or it may be various other types of connectors used to electrically couple a module to a tray. Mounting plate  502  may be constructed out of a metal. Mounting plate  502  is used to secure connector  500  to a tray: connector  500 , by itself, typically contains no mechanism to allow securing to a tray. Mounting plate  502 , as illustrated, is rectangular, however, it should be realized that various shapes of mounting plate  502  may be used.  
         [0035]    Mounting plate  502  is connected to the main rear plate  504  via shoulder bolt  506 . Mounting plate  504  is typically the rear surface of the tray, upon which connectors are located.  
         [0036]    Spring  508  is suitably placed on the shoulder bolt between mounting plate  502  and main rear plate  504 . Spring  508  is depicted as being a coil spring in FIGS. 5A and 5B, however, other forms of springs, such as rubber bushings, leaf springs, pneumatic springs, etc., may be used. Mounted on top of the shoulder bolt over the mounting plate is a guide pin  510 . Guide pin  510  is tapered such that one end has a smaller diameter than the other end. The end with the smaller end is the end farthest away from the mounting plate  502 . Guide pin  510  may be configured such that it is threaded. Therefore, guide pin  510  may be threaded onto shoulder bolt  506 . In this manner mounting plate  502  is secured onto shoulder bolt  506 .  
         [0037]    An orthogonal view of a rear plate of a tray is shown in FIG. 5B, with connector  520  shown in addition to connector  500 , mounted in a similar manner. It should be remembered that a typical tray may contain multiple connectors.  
         [0038]    [0038]FIG. 6 illustrates a portion of panel face  602  that mates with the rear plate  400  of FIG. 5B. Connector  600  is a connector that connects to connector  500  of FIG. 5A. For example, if connector  500  is a female D-sub connector, connector  600  would be a male D-sub connector.  
         [0039]    Connector  600  is mounted on the panel face in any of several different manners. For example, connector  600  may be affixed into panel face  602  with several screws  606 , as illustrated in FIG. 6, or connector  600  may be riveted into panel face  602 . Guide hole  630  is drilled into the mounting plate at a location such that, when the module is inserted into the tray, guide pin  510  interfaced with guide hole  630 . Guide holes  620 ,  622 , and  632  are drilled in a similar manner to correspond to other guide pins.  
         [0040]    An exemplary system of an embodiment of the present invention operates in the following manner. The module with panel face  600  is inserted into the tray. As the module is further inserted into the tray, guide pin  510  engages with guide hole  630 . The connector setup of the mounting plate  502 , connector  500 , shoulder bolt  506 , and spring  508  may be configured such that the connector setup “floats”. Connector  600  and connector  500  do not have to be perfectly aligned with each other because connector  500  is free to move in three mutually-perpendicular directions (up-down, left-right, and front-back). The length of guide pin  510  is chosen such that guide pin  510  engages with guide hole  630  before connector  500  and connector  600  engage with each other. Therefore, guide pin  510  may protrude from mounting plate  502  to a greater extent than connector  500  protrudes from mounting plate  502 .  
         [0041]    This additional degree of freedom allows connectors  500  and  600  to mate even if the module upon which connector  600  resides is slightly longer or shorter than what is nominal.  
         [0042]    Spring  508  has several other functions as well. When a floating bushing as in FIG. 4A and FIG. 4B is used, the connector tends to settle at the bottom of its possible locations, as explained above. The system shown in FIG. 5 alleviates that problem: the spring tension forces that mounting plate and connector to be centered in the hole in which the shoulder bolt is mounted.  
         [0043]    The system of FIG. 5 has a further advantage: as the module is being inserted into the tray, the guide pin  510  connects with the guide hole  630 . Then the flanges of connectors  500  and  600  engage. By this time, the two connectors have been aligned by guide pin  510  and guide hole  600  such that the flanges are in alignment. As the pins and slots of connectors  500  and  600  engage, spring  508  helps make the connection by pushing the two connectors towards each other.  
         [0044]    The use of the spring has a further advantage. In a vibration-prone environment, such as an airplane cockpit, the connectors may have a tendency to disconnect from each other. If the connectors are screwed together, there is no such problem, however, in a blind mating context, it is very difficult and inconvenient to screw the connectors together. The spring provides a force that keeps the connectors together and gives the connectors freedom of movement so the module can move within the tray while still maintaining connection.  
         [0045]    [0045]FIG. 7 shows an alternative embodiment of the present invention. In this embodiment, the locations of the guide pins and the guide holes are reversed. The guide pins are located on the modules and the guide holes are located on the mounting plate.  
         [0046]    More specifically, guide pins  702  and  703  are mounted on the rear of module  704  that is inserted into the tray Guide pins  702  and  703  are astride connector  700  and may protrude from rear plate  704  to a greater extent than does connector  700  so as to interface with guide holes  712  and  713  before connector  700  interfaces with connector  710 . Connector  700  and connector  710  are analogous to connectors  500  and  600  of FIG. 5 and FIG. 6. Guide pins  702  and  703  are analogous to guide pins  510 .  
         [0047]    The tray may be configured as follows. Connector  710 , which connects with connector  700 , is mounted on mounting plate  714 . On either side of connector  710  are guide holes  712  and  713 , which accept guide pins  702  and  703 , respectively. Guide holes  712  and  713  may be configured such that guide holes  712  and  713  also serve to secure connector  700  to mounting plate  714 .  
         [0048]    Mounting plate  714  is attached to guide pin block  726  with shoulder bolts  716  and  718 . Nuts  717  and  719  secure mounting plate  714  to bolts  716  and  718 . Mounting plate  714  is configured similarly to mounting plate  502  of FIG. 5. Springs  722  and  724  are shown mounted on the shoulder bolts in between mounting plate  714  and guide pin block  726 . Guide pin block  726  rests on rear plate  720  of the tray. Guide pin block  726  is a representation of a main structural rear support analogous to rear main plate  504  illustrated in FIG. 5.  
         [0049]    The operation of this embodiment is analogous to the operation of the embodiment described above. When the module is inserted into the tray, guide pins  702  and  703  engage guide holes  712  and  713 . The interaction between guide pins  702  and  703  and guide holes  712  and  713  aligns connector  700  and connector  710 . Therefore, as the module is inserted further into the tray, connector  700  aligns with connector  710  so that the connectors attach to each other as appropriate. Springs  722  and  724  help to provide the connective force necessary to seat the connectors with each other as well as allowing connector  710  to float to a more appropriate position to connect with connector  700 .  
         [0050]    The above description presents exemplary modes contemplated in carrying out the invention. The techniques described above are, however, susceptible to modifications and alternate constructions from the embodiments shown above. Other variations and modifications of the present invention will be apparent to those of ordinary skill in the art, and it is the intent of the appended claims that such variations and modifications be covered. For example, while the invention has been described with respect to D-sub connectors, it should be appreciated that this invention can operate with any type of connector of any shape, such as a round connector or a rectangular connector, PCMIA-type connections, ARINC style connections, IEC-power connectors, or any other type of connector. Furthermore, while this invention has been described with respect to aircraft equipment, it should be appreciated that the present invention will operate in any type of environment where blind mating is desirable, including, but not limited to, other types of rack mounting; computer servers; dashboards of cars, trucks, and boats; laptop compuer docking stations; communication equipment; cellular phone chargers, and the like. In addition, it should be understood that the various parts of the present invention can be made with a number of different materials, including, but not limited to, stainless steel and aluminum, without effecting the operability of the invention.  
         [0051]    Consequently, it is not the intention to limit the invention to the particular embodiments disclosed. On the contrary, the invention is intended to cover all modifications and alternate constructions falling within the scope of the invention, as expressed in the following claims when read in light of the description and drawings. No element described in this specification is necessary for the practice of the invention unless expressly described herein as “essential” or “required.”