Patent Publication Number: US-6699059-B2

Title: Electrical connector assembly comprising locking part

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field of the Invention 
     The present invention belongs in a technical field of an electrical connector assembly. Particularly, the present invention relates to an electrical connector assembly comprising a first component and a second component having a locking element which permits electrical contact points of the first component to be short-circuited with each other when the first component and the second component are not adequately connected with each other and permits the short-circuit to be released when those components are adequately connected with each other. 
     2. Description of the Prior Art 
     An airbag system comprises an airbag assembly and an electric or electronic control system which are assembled in a hidden compartment of a driver&#39;s cabin of a vehicle. The control system is connected with the airbag assembly via a wire harness. The wire harness is provided with a typical electrical plug and jack connector assembly, to allow a simple way for the airbag assembly and the control system to be electrically interconnected after assembled separately. 
     This connector assembly is provided with a so-called short-circuit clip. The short-circuit clip is a small metal element arranged in such a manner that the wires can be electrically short-circuited with each other within the plug or jack before the plug and the jack are engaged. The short-circuit clip is arranged as a safety device to prevent improper operation of the airbag assembly caused by leakage of electrical charge or improper connection in the course of production. 
     When the electrical connector assembly is accurately connected, the safety device using the short-circuit clip intended for electrical short circuit must be shifted to a non-short-circuit position. U.S. Pat. No. 5,275,575 and JP Patent No. 2647336 disclose the electrical connector assembly with locking element which is so designed as to release the electrical short circuit provided by the safety device. This electrical connector assembly is so structured that it does not operate until the components are both put in their completely engaged position and the locking element is shifted to its locking position. Also, the locking element serves to prevent the both components of the connector assembly from being disconnected accidentally after combined. 
     However, to bring the electrical connector assembly into the completely connected state requires a two-step motion comprising the first step motion of inserting the both components for fitting to each other and the second step motion of inserting the locking element into the both component to its locking position. Besides, the locking element is integrally mounted on one of the both components via a flexible arm, and as such provides an increased size of the one of the components and thus makes it hard to handle the electrical connector assembly. 
     Also, U.S. Pat. No. 5,314,345 and JP Patent No. 2647335 disclose the electrical connector assembly that is so designed that the electrical short circuit by the short-circuit clip can be released by the accurate connection of the both components, while also, the connection between the both components can be prevented from being disconnected accidentally by the insertion of the locking element. 
     However, in those references also, to bring the electrical connector assembly into the accurately connected state requires the same two-step motion, as is the case with U.S. Pat. No. 5,275,575. In addition, the provision of the locking element provides an increased size of the one of the components and thus makes it hard to handle the electrical connector assembly. 
     Thus, the both types of electrical connector assemblies as mentioned above adopt substantially the same basic structure that the both components are engaged with each other by themselves and the locking element merely serves to aid in the engagement of the both components themselves. Thus, the both types of electrical connector assemblies have no particular structure to carry out the function of preventing the connection between the both components from being disconnected accidentally, for example, when an external force acts on the plug. 
     SUMMARY OF THE INVENTION 
     It is the primary object of the present invention to provide an electrical connector assembly having the features that a connecting motion of the both components and a pressing motion of the locking element to release the short circuit of a short-circuit element in one of the both components can be carried out in the same motion, that the entire connector assembly can be designed compact, and that the connection between the both components can be prevented from being disconnected accidentally when an external force acts on the electrical connector assembly. 
     In accordance with one aspect of the invention, there is provided an electrical connector assembly comprising: (1) a first component for supporting a first electrical connector element; (2) a second component for supporting a second electrical connector element inserted in the first electrical connector element to be fitted therein; (3) a short-circuit element, fitted in the first component, for electrically short-circuit the first electrical connector element; and (4) a locking element engageable with the second component in a locked manner, the locking element being so structured that when the second component is inserted in the first component to be fitted therein, the locking element can make the short-circuit element move back to its non-short-circuit position and also can move to engage with the first component, wherein the first component and the second component are locked against disconnection by the engagement of the locking element with the first component. Preferably, a direction for the second component to be inserted in the first component is identical with a direction for the locking element to move to engage with the first component. 
     According to this construction, the engagement of the both components in such a relation as to be locked against disconnection and the electrical connection therebetween can be provided via the locking element. Further, the release of the short circuit of the short-circuit element in the other component can also be achieved via the locking element. Besides, the locking element is projected from the one component to only an extent necessary for the locking element to be pressed down so as to engage with the other component, the electrical connector assembly can be made compact as a whole. Furthermore, the connecting motion of the both components and the pressing motion of the locking element to release the short circuit of the short-circuit element in the one component can all be carried out in the same motion. 
     These and other objects, features and advantages of the invention will become more apparent upon a reading of the following detailed specification with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings: 
     FIG. 1 is a perspective view showing the entire structure of a connector assembly or electrical connector assembly used with an airbag system; 
     FIG. 2 is a perspective view, as viewed from bottom, of the second component in which a locking element is locked; 
     FIG. 3 is a perspective view, as viewed from top, of the locking element; 
     FIG. 4 is a perspective view, as viewed from bottom, of the locking element; 
     FIG. 5 is a perspective view of a short-circuit element; 
     FIG. 6 is a perspective view of a short-circuit clip; 
     FIG. 7 is a cross sectional view showing the initial connection state of the second component with the first component in which the locking element is in its first position; 
     FIG. 8 is a cross sectional view showing an intermediate connection state of the second component with the first component; 
     FIG. 9 is a cross sectional view showing an intermediate connection state of the second component with the first component; 
     FIG. 10 is a cross sectional view showing a complete connection state of the second component with the first component; 
     FIG. 11 is a cross sectional view showing the initial connection state of the second component with the first component in which the locking element is in its second position; 
     FIG. 12, which corresponds to FIG. 11, is a longitudinal sectional view showing the initial connection state of the second component with the first component; 
     FIG. 13, which corresponds to FIG. 10, is a longitudinal sectional view showing a complete connection state of the second component with the first component; and 
     FIG. 14 is a cross sectional view, illustrating the function of preventing the connection between the both components from being disconnected accidentally when an external force acts on the second component. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the following, an embodiment of the present invention will be described. It is to be noted that only a certain preferred embodiment of the present invention is shown for convenience of explanation and is not to be construed as limiting the present invention. 
     The present invention is particularly suitably applicable to an airbag system for restraining vehicle occupants and, accordingly, the application to the airbag system is illustrated here as an example of the preferred embodiments of the present invention. It is to be understood, however, that the present invention is applicable within a wider range for various different environments and various intended objects, without limiting to the application to the airbag system. 
     Referring particularly to the accompanying drawings, there is shown in FIG. 1 details of the entire structure of a connector assembly or an electrical connector assembly  1  used with the airbag system. In this diagram, there is shown the connector assembly  1  before connection, which comprises a first component  2  structured in the form of a jack and a second component  3  structured in the form of a plug which is insertable in the first component  2  to be fitted in it. 
     The first component  2  is provided in the form of a part of an airbag igniter (which is sometimes referred to as a squib) to be electrically connected to an airbag system control system. The igniter is an explosive device which is burnt when sufficient electric energy is applied to it through two conducting wires  33 . The burning of the igniter triggers the gas generating material to be ignited and, as a result of this, the airbag is inflated. 
     A short-circuit element  4  is fitted in the first component  2  with a press-fit. The short-circuit element  4  puts contacts of the first component  2  into the short-circuited state until the components  2  and  3  are mechanically and electrically connected. 
     The second component  3  is electrically connected with the control system. It is also connected with the first component  2 . A locking element  5  is held in the second component  3  in its locked state. 
     The functions and mutual relations of these various components will be clarified from the following description. Also, as will be obvious from the following description, the second component  3 , the short-circuit element  4  and the locking element  5  are preferably formed of proper non-conductive plastic material, except various kinds of wires and contacts. 
     Referring particularly to the first component  2 , this component  2  is formed to have a cylindrical body  10  forming an opening or a socket  11  therein. This first component  2  is shown in FIGS.  1  and  7 - 14 , in particular. FIGS. 7-11 and  14  illustrate in section the connected state of the second component  3  to the first component  2  and these sectional views are taken along the widthwise direction of the second component  3 . Similarly, FIGS. 12 and 13 illustrate in section the connected state of the same and these sectional views are taken along the longitudinal direction of the second component  3 . The body  10  forming the socket  11  therein can be directly built in its related structure such as an igniter housing. Further, the socket  11  may be formed as a separate element so that it may be added to its related structure. In either configuration, the body  10  forming the socket  11  therein terminates at a bottom wall  12 , as shown in FIG. 7, for example. Extended from the bottom wall  12  are a pair of first, conductive, male electrical connector elements or pins  13  formed of metal. These two pins  13  are connected to their respective conducting wires of the airbag igniter (not shown) in any conventional manner. The igniter is electrically energized through the pins  13  so that it can be ignited. 
     The socket  11  has an inclined surface  14  formed at an entrance thereof. The socket  11  has a locking recess  15  formed in its inner surface to extend continuously in the circumferential direction. As well shown in FIGS. 7 and 11, the inclined surface  14  serves to receive locking portions  52  provided at first legs  51  of the locking element  5 , as mentioned later, and produce a deforming moment to move the locking portions  52  toward the center. The locking recess  15  serves to receive the locking portions  52  of the locking element  5  and keep it in its engaged state, as best shown in FIG.  10 . 
     Also, the socket  11  has a semicircular concave portion at one location around the entrance thereof, though not shown in any diagrams. The semicircular concave portion is so formed as to fit with a corresponding semicircular lug (not shown) provided in the short-circuit element  4  when the short-circuit element  4  is disposed in the socket  11 . This determines the setting of orientation of the short-circuit element  4 , as shown in FIG.  1 . 
     The short-circuit element  4  is received in the socket  11 . The short-circuit element  4  serves to provide the short-circuit by keeping the male electrical connector elements  13  in the state of being electrically connected therebetween until the second component  3  is inserted in the first component  2  to fit with it and further the locking element  5  locked in the second component  3  is brought into engagement with the first component  2 . 
     Shown in FIG. 5 is a perspective view of the short-circuit element  4 . The short-circuit element  4  has a molded plastic body  21  of a generally cylindrical shape having a dimension to tightly fit in the socket  11 . The body  21  of the short-circuit element  4  is provided, at its sides on the top, with semi-columnar projecting portions that are extended short downwardly therefrom so as to correspond in location and size to the concave portions provided in the socket  11  so that they can be snugly received in the concave portions, though not shown in FIG.  5 . Those projecting portions serve to determine the orientation of the short-circuit element  4  with respect to the socket  11 . Further, the body  21  of the short-circuit element  4  has an opening  23  into which the male electrical connector elements or pins  13  are extended passing therethrough. The opening  23  is formed to open to the top at the center portion of the short-circuit element  4  and to both lateral sides thereof. FIGS. 7-11 and  14  show the sectional views including the section of the opening  23 . 
     A short-circuit clip  24  is held in the body  21  of the short-circuit element  4 . The short-circuit clip  24  is formed of conductive material having elasticity such as spring steel. A part of the short-circuit clip  24  is deflected to the direction of its abutting with the pins  13 . The abutment of the short-circuit clip  24  with the pins  13  provides an electrical short-circuit therebetween. 
     A perspective view of the short-circuit clip  24  is shown in FIG.  6 . The short-circuit clip  24  comprises a plate-form base  25 , a pair of legs  26  folded back at the top of the base  25  and extending downward therefrom and a pair of abutting portions  27  folded at an angle of 90 degree at the lower end portions of the legs  26 . Each of the legs  26  is folded and deflected stepwise in the direction of its being away from the base  25 . The abutting portions  27  of the short-circuit clip  24  are brought into abutment with lateral sides of the both pins  13  to electrically connected therewith. As shown in FIG. 5, the short-circuit clip  24  is held in the body  21  of the short-circuit element  4 , with its base  25  inserted in a slit-like recess  28  of the short-circuit clip  4  so as not to slip off. 
     The short-circuit element  4  is set in position in the socket  11 , so that the lateral sides of the two pins  13  are abutted with the abutting portions  27  of the short-circuit clip  24  at the lower portions thereof, to be electrically connected therewith. The two pins  13  extend upwardly within the opening  23 . In FIG. 12, in which there is shown a longitudinal sectional view showing the initial connection state of the second component  3  with the first component  2 , there is shown the state that the abutting portions  27  of the short-circuit clip  24  are in contact with the pins  13 . 
     The second component  3  of the connector assembly or electrical connector assembly  1  will be best understood with reference to FIGS. 1,  2  and  7 - 14 . As shown in these figures, the second component  3  includes a body portion  32  or a central plug portion  31  extending downwardly and supporting a pair of electrical terminals  30  which are in the form of second female connector elements (See FIGS. 2,  7  and  12 ). The electrical terminals  30  are electrically connected with the conductors  33 . These electrical terminals  30  are formed to have configuration and size to receive the pins  13  of the first component  2  therein. 
     For example, as shown in FIGS. 7 and 12, the electrical terminals  30  built in the central plug portion  31  each extend from the tubular terminal portions forming the second female connector element and change in direction in a generally L-form so as to be connected with the two conductors  33 . The conductors  33  are the insulation armored wires. These wires are peeled at the ends thereof so as to be electrically and mechanically attached to the electrical terminals  30 . The attachment of the wires is usually performed by press-fitting a part of the electrical terminals  30  around the bare wires at the ends thereof in any conventional manner. 
     In FIG. 1,  2  or  12 , the second component  3  includes the central plug portion  31  and the box-shaped body portion  32  arranged in the generally L-form with respect to the central plug portion  31 , as previously mentioned. The body portion  32  comprises upper body portion  32   a  and a lower body portion  32   b  which can be diverged from each other with their one ends coupled via a flexible coupling portion  34 . The upper and lower body portions  32   a  and  32   b  can be folded on the coupling portion  34  to form a combined body of a generally rectangular parallelepiped form. Specifically, these two body portions  32   a  and  32   b  are formed into the combined body of generally rectangular parallelepiped form by the engagement of a pair of spaced, elastic tab extensions  37  extending downwardly from the end of the upper body portion  32   a  with a pair of engaging portions (not shown) formed at the end of the lower body portion  32   b.  This can allow the two body portions  32   a  and  32   b  of the second component  3  to be retained in a proper engagement relation therebetween, as shown in FIGS. 1 and 2. 
     In FIG. 12, the second component  3  has a box-shaped space  32   c  in a part thereof between the upper body portion  32   a  and the lower body portion  32   b.  A ferrite bead  35 , through which the conductors  33  pass, is placed in the space  32   c.  The ferrite bead  35  is a generally box-shaped homogeneous substance having two tubular thru holes extending in parallel with each other, and the conductors  33  pass through the thru holes of the ferrite bead  35 . 
     The central plug portion  31  has a generally square cylinder form and has a ridge  43 , as best shown in FIG.  2 . The ridge  43  is formed and arranged in size and location to engage with a recess  29  opening to the top of the short-circuit element  4  shown in FIG.  1 . The engagement of the ridge  43  in the recess  29  ensures a proper connection between the two electrical terminals  30  of the second component  3  and the two pins  13  of the first component  2 . 
     As best shown in FIG. 1, the upper body portion  32   a  of the second component  3  has a wide shallow recess  45  formed on an upper surface thereof at a location corresponding to the central plug portion  31 . It also has a perforated opening, though not shown, in which the first legs  51  and the second legs  53  of the locking element  5  are inserted from the shallow recess  45  toward the central plug portion  31 . When the locking element  5  is inserted in the second component from the perforated opening, the central plug portion  31  is so placed that its lateral sides are held in sandwich relation by the locking element  5 . As well shown in FIGS. 2 and 7, the central plug portion  31  has, in its terminal holding portions  31   a  holding the electrical terminals  30  and spaced widthwise from each other, outwardly projecting lug portions  31   b  formed to extend along a part of a recessed portion  54  (mentioned later) formed in the locking element  5 . 
     FIGS. 3 and 4 show a perspective view of the locking element  5 . The locking element  5  includes a head portion or pressing portion  50 , a pair of first legs  51  extending downwardly from both widthwise sides of the pressing portion  50 , and a pair of second legs  53  arranged in a row and extending downwardly from one lengthwise end of the pressing portion  50 . The first legs  51  and the second legs  53  are so disposed as to be in the planes meeting at generally right angles with each other. Specifically, the first legs  51  and the second legs  53 , which are so disposed as to be in the planes meeting at generally right angles with each other, are arranged in such a manner that the first legs  51  are spaced to confront each other and also the second legs  53  are arranged to be symmetric with respect to a slit  58 . These legs are formed and arranged in size and location to be inserted in the perforated opening formed in the upper body portion  32   a  of the second component  3 . This can allow the locking element  5  to be retained in a proper engagement relation, as shown in FIG.  1 . 
     Each of the first legs  51  has the outwardly projecting locking portion  52  at a lower portion thereof on the opposite side to the mutually confronting side. The locking portions  52  are formed and arranged in size and location to be engageable in the locking recess  15  formed in the socket  11 , as best shown in FIG.  10 . This can provide the result that when the locking element  5  is pressed in the direction for the first and second components  2  and  3  to be connected with each other, the both components are brought into engagement in such a manner as to be locked against disconnection via the locking element  5 . 
     As well shown in FIG. 4, the first legs  51  have recessed portions  54  at opposed portions thereof on substantially the back sides of the locking portions  52 . The recessed portions  54  are so formed as to be engageable with the lug portions  31   b,  which are provided on the terminal holding portions  31   a  of the central plug portion  31  disposed in sandwich relation between the first spaced legs  51 , when the locking portions  52  are in engagement in the locking recess  15 . This ensures that the first component  2  and the second component  3  are held in their connected state further tightly. This connected state is well shown in FIG.  14 . If an external force acts on the second component  3  when the locking portions  52  are in engagement in the locking recess  15 , the terminal holding portions  31   a  having flexibility will be deflected so that the lug portions  31   b  can press the recessed portions  54  in the direction for the locking portions  52  and the locking recess  15  to be engaged with each other. Thus, the first legs  51  confronting each other are pressed from the inside and stretched out. As a result of this, even when an external force acts on the electrical connector assembly  1 , the first component  2  and the second component  3  can be locked further tightly against disconnection to prevent the connection between the both components from being disconnected accidentally. The related actions of the lug portions  31   b  with the first legs  51  are indicated by arrows in FIG.  14 . This construction can easily provide the structure to prevent the both components from being disconnected accidentally. 
     In FIGS. 3 and 4, the first legs  51  have, at intermediate portions thereof above the locking portions  52 , two rectangular recessed portions  55  which are spaced apart in a vertical direction or in a direction for the second component  3  to be inserted in the first component  2 , so as to face outwardly. The recessed portions  55  each comprise, in lower-to-upper order, a first recessed portion  55   a  and a second recessed portion  55   b.  These two recessed portions  55  are each engageable with a retaining projection  56  of the second component  3 , as best shown in FIGS. 7 and 11. This allows the locking element  5  to be locked at the two positions when inserted in the second component  3 . It is to be noted that the related position of the locking element  5  when locked at the first recessed portions  55   a  is defined as the first position and the related position of the locking element  5  when locked at the second recessed portions  55   b  is defined as the second position. The first recessed portions  55   a  are so formed that when the locking element  5  is in the first position, it can be locked, with the pressing portion  50  of the locking element  5  and the front ends of the first legs  51  projected from the second component  3  in the directions opposite to each other, to form a generally T shape (See FIG.  7 ). The second recessed portions  55   b  are so formed that when the locking element  5  is in the second position, it can be locked, with the pressing portion  50  nearly sunk in the shallow recess  45  of the second component  3  and only the front ends of the first legs  51  projected from the second component  3 , to form a generally L shape (See FIGS. 1,  11  and  12 ). 
     As best shown in FIGS. 3 and 4, the second legs  53  are each formed in a plate-like form and are extended downwardly side by side, with the slit  58  sandwiched therebetween. The slit  58  extends from the backside of the head or pressing portion  50  to the ends of the second legs  53 . When the second legs  53  are inserted up to their roots in the penetrated opening, the head  50  is completely accommodated in the shallow recess  45 . The provision of the slit  58  can allow for a sufficient mechanical strength of the electrical connector assembly by the insertion of the locking element  5 , even when the second component  3  has the penetrated opening at its upper body portion  32   a.  As best shown in FIGS. 12 and 13, when the locking element  5  is pressed in the first component  3 , the second legs  53  are advanced up to the folded portion of the short-circuit clip  24 . This serves to move the abutting portions  27  away from the pins  13  to release the electrical connection with the pins  13 . 
     As described above, the locking element  5  has the pair of first legs  51  and the pair of second legs  53 , and the first legs  51  and the second legs  53  are so disposed as to be in the planes meeting at generally right angles with each other. In addition, the first legs  51  and the second legs  53 , which are so disposed as to be in the planes meeting at generally right angles with each other, are arranged in such a manner that the first legs  51  are spaced to confront each other. This construction can provide the results that the locking element  5  can allow the both components  2  and  3  to be engaged with each other in such a manner as to lock the both components against disconnection and can also allow the both components  2  and  3  to be electrically connected with each other, and can further allow the short circulation provided by the short-circuit element  4  in the first component  2  to be released with ease. 
     As will be mentioned later, the locking element  5 , when pressed in, can allow the first legs  51 , which have the locking portions  52 , one for each, at the opposite side to the mutually confronting side, to be deflected, first, and then resiliently restored to engage in the locking recess  15  formed in the first component  2 , so as to fit in it. This construction can provide the results that the locking element  5  can allow the both components  2  and  3  to be engaged with each other in such a manner as to lock the both components against disconnection and can also allow the both components  2  and  3  to be electrically connected with each other, and can further allow the short circulation provided by the short-circuit element  4  in the first component  2  to be released with ease. 
     The connector assembly or electrical connector assembly  1  according to the embodiment of the invention is constructed as described above. Now, the connecting operation of the electrical connector assembly  1  will be described with reference to FIGS.  1  and  7 - 13 . As shown in FIG. 1, the short-circuit element  4  is previously fitted in the socket  11  of the first component  2  to provide the electrical short-circuit of the pins  13 , and the locking element  5  is previously locked in position against the second component  3 . Though FIG. 1 shows the state that the locking element  5  is locked in the second position, the locking element  5  may be locked in the first position as well. Also, the locking element  5  can be pressed from either of the positions to engage with the first component  2 , as mentioned later. 
     FIG. 7 shows the state that paralleled portions of the plug portion  31  at the lower end thereof are inserted deep in the socket  11  of the first component  2  by an operator holding both sides of the body portion  32  of the second component  3  with his/her hand. In FIG. 7, the locking element  5  is locked in the first position with respect to the second component  3 . In this position, the locking element  5  is locked, taking a generally T form, with the pressing portion  50  projected upwardly, from which the operator can visually judge that the electrical connection between the first and second components has not yet been completed. This can provide improved working efficiency in the assembling work using the electrical connector assembly  1 . 
     In this electrical connector assembly  1 , whether the locking element  5  is in the first position or in the second position, when the locking element  5  is pressed from that position, the engaging motion of the second component  3  into the first component  2  for a fit therein and the engaging motion of the locking element  5  into the first component  2  can be performed in the continuous motion. Hence, even when the locking element  5  is accidentally pressed by external force and the like acting thereon in the course of the transmission of the electrical connector assembly  1 , such that the locking element  5  is disengaged from the first position and is shifted therefrom to the second position in which the locking element  5  takes the generally L form, the connection beteen the both components  2  and  3  can be provided by simply pressing the locking element  5  as it is, without restoring it to the first position. FIG. 11 shows the initial state of insertion of the locking element  5  into the first component  2 , with the locking element  5  locked in the second position. FIGS. 7 and 11 both show the initial state of insertion of the second component  3  into the first component  2 . In this initial state, the locking portions  52  of the locking element  5  rest on the inclines surface  14  at the entrance of the socket  11  in abutment therewith. 
     When the pressing portion  50  of the locking element  5  is pressed from this state, for example, with a thumb, an inward moment acts on the first legs  51 . FIG. 8 shows the intermediate state of the connection produced when the locking element  5  is pressed from the initial state shown in FIG. 7 in which it is locked in the first position. In this state, the first legs  51  are deflected inwardly by the reaction force acting thereon from the entrance of the socket  11  through the locking portions  52 . The deflection of the first legs  51  operates to disengage the engagement between the first recessed portions  55   a  and the retaining projections  56  simultaneously. This intermediate state is shown in FIG.  9 . In FIG. 9, there is represented the state in which the retention of the retaining projections  56  in the first recessed portions  55   a  is released and the related position of the retaining projections  56  is changed so that the level of the retaining projections  56  can be even with the second recessed portions  55   b.  When the pressing portion  50  is pressed from the state of FIG. 11 in which the locking element  5  is locked in the second position, the locking element  5  is shifted from that state to the intermediate state shown in FIG.  9 . 
     Thus, the first legs  51 , after deflected, are resiliently restored and the locking portions  52  are fitted in the locking recess  15 , as shown in FIG. 10, whereby the engagement between the locking element  5  and the first component  2  is completed. As a result of this, the connection between the first component  2  and the second component  3  comes into the state of perfection. At the same time, the pins  13  are inserted in the electrical terminals  30  built in the plug portion  31  of the second element  3  and thereby the electrical connection therebetween is also achieved. 
     Not only the connection between the first component  2  and the second component  3  but also the release of the short-circulation between the pins  13  provided by the short-circuit clip  24  of the short-circuit element  4  is achieved by the same pressing-down motion of the locking element  5 . The released state of the short circulation is shown in FIGS. 12 and 13. FIG. 12, which corresponds to FIG. 11, is a longitudinal sectional view showing the initial connecting state of the second component  3  with the first component  2 . In FIG. 12, the short circuit of the pins  13  provided by the short-circuit clip  24  still remains. On the other hand, in FIG. 13 showing the state in which the pressing motion of the locking element  5  is completed for engagement, the second legs  53  of the locking element  5  are advanced to the folded portion of the short-circuit clip  24  and thereby the abutting portions  27  are moved away from the pins  13  to release the short circuit of the pins  13 . 
     As described above, the mechanical engagement between the first component  2  and the second component  3  and the electrical fitting connection therebetween are both perfectly completed via the locking element  5  in the same pressing motion of the locking element  5 . For example, if an external force acts on the second component  3  through the cables  33  when the first component  2  and the second component  3  are in the connected state, the terminal holding portions  31   a  of the central plug portion  31  will be deflected and then the lug portions  31   b  at the terminal holding portions  31   a  will bias the recessed portions  54  provided at the first legs  51  of the locking element  5  in the direction for the locking portions  52  and the locking recess  15  to be engaged with each other. As a result of this, the first component  2  and the second component  3  can be locked further tightly against disconnection to prevent the connection between the both components from being disconnected accidentally (See FIG.  14 ). 
     Once the connection of the second component  3  with the first component  2  is completed, it becomes impossible to remove the second component  3  from the first component  2 , unless only the locking element  5  is raised, for example, by using as a lever a sharp-end clip or the like inserted in between the pressing portion  50  of the locking element  5  and the shallow recess  45  of the second component  3 . 
     As described above, according to this electrical connector assembly  1 , the engagement of the both components  2  and  3  in such a manner as to be locked against disconnection and the electrical connection therebetween can both be provided via the locking element  5  and, further, the release of the short circuit by the short-circuit element  4  in the first component  2  can also be achieved via the locking element  5 . Besides, since the locking element  5  is projected from the second component  3  to only an extent necessary for the locking element  5  to be pressed down so as to engage with the second component  3 , the electrical connector assembly  1  can be made compact as a whole. 
     Furthermore, the connecting motion of the both components  2  and  3  and the pressing motion of the locking element  5  to release the short circuit of the short-circuit element  4  can be carried out in the same motion. 
     Moreover, the connecting motion of the both components  2  and  3  and the pressing motion of the locking element  5  to release the short circuit of the short-circuit element  4  can all be carried out in the single motion. 
     In summary, according to the electrical connector assembly  1  according to the illustrated embodiment, the connecting motion of the both components and the pressing motion of the locking element to release the short circuit of the short-circuit element in the one of the both components can both be carried out in the same motion; also the entire connector assembly can be designed compact; and yet the connection between the both components can be prevented from being disconnected accidentally when an external force acts on the electrical connector assembly. 
     While the present invention has been described in its preferred embodiment, it is to be understood that it is intended to cover in the appended claims all variants, modifications, applications and equivalents thereof that will be obvious as fall within the scope of the appended claims upon reading and understanding the specification. 
     For example, the pair of legs  26  of the short-circuit clip  24  may be presented in the form of a sheet of plate. The pair of abutting portions  27  formed by bending the front ends of the legs  26  at an angle of 90 degree may take any suitable configuration to directly contact with the pins  13 , without limiting to the configuration as shown in the illustrated embodiment. 
     Also, the locking element  5  may take a configuration wherein the slit  58  formed between the second legs  53  is not formed. This means that the locking element  5  may take such a configuration that the second leg  53  of a single-sheet-plate form is arranged between the pair of first legs  51  so that a generally U-like shape can be formed by the first legs  51  and that second leg  53 . 
     In addition, the locking element  5  according to the present invention is applicable not only to the electrical connector assembly  1  according to the present invention that is so structured that the locking and the release of the short circuit can both be performed in the same motion, but also to a conventional type of electrical connector assembly that is so structured that the locking and the release of the short circuit are performed by different motions.