Patent Publication Number: US-6210202-B1

Title: Device for locking two mating connectors

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a locking device for joining first and second mating connectors together. 
     2. Description of the Prior Art 
     Electrical connection between two mating connectors is often adversely effected by vibration or an unexpected external force. In order to protect the connection from such disturbances, the mating connectors often have engageable locking devices for securely joining the two connectors together. U.S. Pat. Nos. 5,401,189 and 5,971,790, and Taiwan Patent Application No. 84201383 disclose such connectors. 
     Referring to FIG. 4, a conventional connector comprises a dielectric housing  70 , a plurality of conductive contacts  71  received in the housing  70 , a shield  72  enclosing a front portion of the housing  70  and a pair of locking members  73  for joining the connector and a mating connector (not shown) together. The housing  70  defines a pair of apertures  74  in opposite sides thereof for securely receiving the corresponding locking members  73 . The shield  72  defines a pair of cutouts  78  and a pair of through holes  79  at positions corresponding to the apertures  74  of the housing  70 . Each locking member  73  forms a cantilevered arm  76  having a hook  77  at a free end thereof and a cavity  75  corresponding respectively to the cutout  78  and the through hole  79  of the shield  72 . Each locking member  73  is received in the corresponding aperture  74  of the housing  70  with the arm  76  extending through the corresponding cutout  78  of the shield  72 . The locking member  73  is attached to the housing  70  and the shield  72  by a fastening member such as a screw (not shown), extending through the cavity  75  and the through hole  79 . 
     However, since the locking member  73  is relatively large, the aperture  74  of the housing  70  weakens the integrity of the housing  70 . In addition, since the hook  77  only engages with a locking member of the mating connector (not shown) at a predetermined position, any deviation therebetween will hinder proper engagement. Further, disengagement between the two mated connectors is complicated since the locking members  73  are not provided with an accessible disengaging device. Hence, an improved electrical connector is required to overcome the disadvantages of the prior art. The copending applications of Ser. Nos. 09/361,686 filed Jul. 27, 1999 and 09/364,172 filed Jul. 07, 1999 both of which have the same inventor and the same assignee with the invention, disclose some approaches. 
     BRIEF SUMMARY OF THE INVENTION 
     A first object of the present invention is to provide a locking device having effective guiding means for locking/unlocking two members of the locking device with a minimal force. 
     A second object of the present invention is to provide a locking device which occupies a small amount of space in an insulative housing of an electrical connector in which the locking device is assembled. 
     To fulfil the above objects, a locking device for joining first and second mating connectors together comprises a pair of first locking members and a pair of second locking members respectively retained in opposite sides of the first and second connectors. Each first locking member has a globular engaging portion extending beyond the first connector. Each second locking member has a latch extending beyond the second connector which includes an opening and a transverse bar at a free end thereof. The transverse bar defines an inclined surface and has an arcuate construction for facilitating guidance of a corresponding engaging portion of the first locking member into the opening of the latch. The pair of engaging portions of the first locking members is accommodated in the pair of openings of the second locking members, thereby securely engaging the first and second locking members together. 
     Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded view of two mating electrical connectors and a pair of locking devices in accordance with a preferred embodiment of the present invention; 
     FIG. 1A is a partial enlarged view of FIG. 1; 
     FIG. 2 is a partially cross-sectional top view of an assembly of one of the two mating electrical connectors and a pair of second locking members shown in FIG. 1; 
     FIGS. 3A-3C are partial top views showing two locking members of the locking device in accordance with the preferred embodiment of the present invention being sequentially engaged together; and 
     FIG. 4 is an exploded view of an electrical connector incorporating a conventional locking device. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIGS. 1,  1 A and  2 , a locking device  1  for joining a first connector  2  and a second connector  3  together comprises a pair of first locking members  10  and a pair of second locking members  11  retained in the first and second connectors  2 ,  3 , respectively. The first locking member  10  has a screw portion  101  forming threads thereon and an engaging portion  102 , generally having a globular construction, opposite the screw portion  101 . The screw portion  101  is received in the first connector  2  while the engaging portion  102  extends beyond a mating face  21  of the first connector  2 . A projection  103  is formed proximate the engaging portion  102 , and a gap  104  is defined therebetween. The engaging portion  102  defines a hexagonal opening  1022  at a free end thereof for screwing the screw portion  101  of the first locking member  10  into the first connector  2 . In a preferred embodiment of the present invention, each of the pair of second locking members  11  comprises a rear portion  110 , a front portion  111  and a fulcrum portion  113  positioned between the rear and front portions  110 ,  111  (best seen in FIG.  2 ). The rear portion  110  comprises a resilient strip  117  stamped laterally therefrom and a press portion  118  exposed out of the second connector  3  for manually operating the second locking member  11 . The fulcrum portion  113  is ring-shaped for receiving and rotating about a fulcrum bar  12  in the second connector  3 . Correspondingly, the second connector  3  defines a channel  31  in each of the opposite side edges thereof for movably accommodating the pair of second locking members  11  therein. In an unengaged state, the resilient strip  117  of each second locking member  11  resiliently abuts against an inner peripheral wall  32  of the channel  31  to render the front portion  111  inwardly pivotable about the fulcrum bars  12 . 
     The front portion  111  comprises a latch  112  extending beyond a mating face (not labeled) of the second connector  3  for engaging with the engaging portion  102  of the first locking member  10 . The latch  112  includes an opening  116  and a transverse bar  114  at a free end thereof. The transverse bar  114  generally extends in a front-to-back or mating direction with regard to the connectors  2 ,  3 , which is different from the exposed front portion  111  of the latch  112  which extends forward and outwardly in an oblique direction. The transverse bar  114  further defines an inclined surface  115  in a lateral and distal edge thereof for slidably guiding a selected one of the engaging portions  102  of the first locking members  10  into the opening  116  of the latch  112 . The transverse bar  114  is laterally stamped to form an arcuate construction for facilitating guidance of the selected engaging portion  102  of the first locking member  10  into the opening  116 . 
     Also referring to FIGS. 3A-3C, in operation, a forces F is exerted on the press portions  118  of each second locking members  11  to inwardly move the rear portion  110  which causes an outward movement of the front portions  111  (shown by arrows A) because of the presence of the fulcrum portion  113  and the fulcrum bar  12 , thereby facilitating the engagement of the engaging portions  102  of the pair of first locking members  10  with the front portions  102  of the pair of second locking members  11 . The front portions  111  generally resume to their original positions when the forces F is removed from the rear portions  110  due to the functions of the resilient strips  117  of the rear portions  110 . In this case, the engaging portions  102  of the pair of first locking members  10  are received in the openings  116  of the latches  112  of the pair of second locking members  11  and the transverse bars  114  are received in the gaps  104  of the pair of first locking members and abut against rear portions of the engaging portions  102 , thereby secure engagement of the pair of first locking members  10  with the pair of second locking members  11  is obtained. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.