Abstract:
A pair of terminals includes contact parts to be contacted with each other for conduction. Respective one of the pair of terminals has respective one of discharge parts formed integrally thereto. The discharging parts are contacted with each other before contacting the contact parts. The discharging parts are disengaged from each other after disengaging the contact parts.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a terminal assembly, and, more particularly, to a terminal assembly employed for male and female connectors to be mated and connected each other. 
     A connector assembly has a female and male connector mated with each other for connection. The female connector has a male connecting terminal accommodated and fixed in a female connector housing. The male connecting terminal is disposed at its distal end to protrude into a hood of the female housing. 
     On the other hand, the male connector has a female connecting terminal accommodated and fixed in a male connector housing. The female terminal is formed at its distal end in a tubular shape, in which the male terminal is to be inserted from its distal end. The female terminal has a contact spring piece formed at its distal end, the spring piece being folding back diagonally in the tubular space. 
     In the connector of the structure, when mating the male and female connectors, the male terminal is inserted in the end of female connector from its end to be contacted with the spring piece, so that conduction is achieved. 
     SUMMARY OF THE INVENTION 
     In the above-described connector assembly, however, when the female and male connectors in conduction are mated with each other, the distal ends of the male and female terminals come into contact with each other at first, and an arc discharge generates at contacts to deteriorate or damage the contacts. When disengaging the connectors, the distal ends of male and female terminals last detach from each other, and an arc discharge generates at the distal ends to deteriorate or damage the contacts. 
     The deterioration or damage generates to the contacts prevents the contacts of the male and female terminals from good conduction, and connector is degraded in reliability. 
     An object of the present invention provides a terminal assembly with contact protection function which makes ends of connecting terminals to be connected with each other prevented from deterioration or damage for protecting the ends of both the connecting terminals. 
     According to a first aspect of the invention, there is provided a terminal assembly. The assembly includes a pair of terminals including contact parts to be contacted with each other for conduction. Respective one of the pair of terminals has respective one of discharge parts formed integrally thereto. The discharging parts are contacted with each other before contacting the contact parts. The discharging parts are disengaged from each other after disengaging the contact parts. 
     Preferably, the respective one of the discharge members is a spring piece extending forward from respective one of side parts of the pair of the terminals in a mating direction. 
     According to the second aspect of the invention, a terminal assembly includes a first terminal having a first contact. The first terminal has a first discharge part with a second contact extending from the first terminal. The second contact is displaced from the first contact at a first displacement S 1 . The assembly includes a second terminal to be mated with the first terminal for conduction. The second terminal has a third contact to be contacted with the first contact. The second terminal has a second discharge part with a fourth contact extending from the second terminal. The fourth contact is to be contacted with the second contact. The fourth contact is displaced from the third contact at a second displacement S 2 . A relationship of the first displacement S 1  and the second displacement S 2  is that S 1 +S 2 &gt;0. 
     Preferably, the first terminal has a protrusion including the first contact at a distal end thereof. 
     According to a third aspect of the invention, a connector assembly is adapted for a terminal assembly according to the second aspect. A first connector includes a first housing accommodating the first terminal. A second connector includes a second housing to be mated with the first housing. The second housing accommodates the second terminal. 
     According to the aspects, the discharge members provided to respective one of the pair of terminal are contacted with each other before contacting the contact parts of both the terminals. When disengaging the terminals, the discharging members are disengaged from each other after disengaging the contact parts. If an arc discharge generates between the discharge members, detrimental effect to the contact parts is prevented from extending. Thus, the contact parts of the terminals do not have deterioration and damage due to the arc discharge, and the terminals as well as the connectors are improved in reliability. 
     The discharge members are spring pieces extending from a pair of side parts of the terminals, and the discharge members are at a distance apart from each other, so that an arc discharge effect is prevented from extending to the contact parts. 
     The discharge members securely contact before contacting the contact parts and the discharge members securely contact at disengagement of the contact parts. Thus, discharge members are securely disengaged from each other after disengaging the contact parts, and detrimental effect to the contact parts is prevented from extending. 
    
    
     BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
     FIG. 1 is a sectional view of a connector assembly of an embodiment, for which connecting terminals of the invention are adapted. 
     FIG. 2 is a perspective view of a male connecting terminal of an embodiment; 
     FIG. 3 is a perspective view of a female connecting terminal of an embodiment; 
     FIG. 4 is a sectional view of another embodiment; and 
     FIG. 5 is a sectional view of another embodiment. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An embodiment of the present invention will hereby be explained with reference to the drawings. 
     As shown on FIG. 1, a connector assembly  10  includes a female connector  11  and a male connector  12 . The female connector  11  has a male connecting terminal  15  accommodated and disposed in a female housing  14  formed with a fit-in hood part  13  at a front end of the housing  14 . The male connector  12  has a female connecting terminal  17  accommodated and disposed in a male housing  16  to be fitted in a hood  13  of the female housing  14  at a front end of the housing  16 . 
     The male terminal  15 , as shown on FIGS. 1 and 2, a male terminal body  18  supported by the female housing  14 , a contact protrusion  19  provided at a front end of the terminal body  18 , a dummy tab  20 , as a dummy contact, extending forward from a side part at the front end of the terminal body  18  in substantially parallel with and at a predetermined distance apart from the protrusion  19 . In the embodiment, the tab  20  and the protrusion  19  are set each other at substantially equal length. The tab  20 , as shown on FIG. 2, includes a base part  20   a,  a first part  20   b  extending diagonally from the base part  20   a  to be apart from the protrusion  19 , and a second part  20   c  extending from the first part  20   b  in substantially parallel with the protrusion  19 . Between the base part  20   a  and the first part  20   b,  a third part  20   d  is bent. Between the first part  20   b  and the second part  20   c,  a fourth part  20   e  is bent. The second part  20   c  and the protrusion  19  include ends  20   f,    19   a  in substantially accordance with each other in a mating direction F 1 . 
     The male terminal body  18  includes wire holding pieces  21  for holding a wire (not shown on Figs.) at a rear part thereof. 
     The female housing  14  to accommodate the male terminal  15  of the structure has a terminal accommodation space  14 A inside, the space  14 A accommodating a male terminal body  18  of the male terminal  15 . The protrusion  19  of the male terminal  15  passes through an intermediate wall  14 B to protrude into the hood part  13 , the walls  14 B separating the space  14 A and a space in the hood part  13 . 
     The dummy tab  20  of the male terminal  15  protrudes into the hood part  13  through an insertion hole  14   c  formed to the intermediate wall  14 B. The hood part  13  includes a tab holding wall  13 A holding the tab  20  along an outer side of the tab  20  therein. The wall  13 A and an outer wall of the hood part  13  has an insertion space  13 B formed therebetween for inserting a front end of the male housing  16  of the male connector  12 . 
     The male housing  16  has a front wall  16 A at its front end to hold the female terminal  17  to be inserted from its rear end. The front wall  16 A has a protrusion guide hole  16 B provided therethrough at its central part in its traverse direction. The front wall  16 A includes a tab insertion hole  16   c  made at a periphery thereof for inserting the wall  13 A formed to the female housing  14  and a tab  20  held by the wall  13 A. 
     The female terminal  17  to be accommodated in the male housing  16 , as shown on FIGS. 1 and 3, includes a female terminal body  22  in a substantially rectangularly tubular shape, which is accommodated and held in the male housing  16 , a dummy spring  23 , as a dummy contact, protruding forwardly diagonally outward from a side part at a front end of the female terminal body  22 , and pairs of terminal holding pieces  24  formed at a rear part of the female terminal body  22 . 
     The female terminal body  22  includes a contact spring  25  as a contact part, being folded back inwardly at a proximal end  25   a,  at a periphery of a front end opening part thereof. When mating the female and male connectors  11 ,  12 , the spring  25  is to be contacted with the spring  19 . The spring  23 , configured to protrude froward from the female terminal body  22 , is disposed in the insertion hole  16 c formed to the male housing  16  so as to be contacted with the tab  20  to be passed through the hole  16   c.  When mating both the connectors  11 ,  12 , the spring  23  and the tab  20  come to contact before the protrusion  19  and the spring  25  do. The spring  23  includes a base part  23   a  on the terminal body  22 , a first part  23   b  extending diagonally outward from the base part  23   a,  and a second part  23   b  extending from the first part  23   a  in substantially parallel with the terminal body  22 . The base part  23   a  and the first part  23   b  have a third part  23   d  bent therebetween. The first part  23   b  and the second part  23   c  have a fourth part  23   e  bent therebetween. The second part  23   c  has a distal end  23   f  positioned in front of a proximal end  25   a.    
     The distal end  19   a  of protrusion  19  is first contacted with the proximal end  25   a  of contact spring  25  or the front end  22   a  of female terminal body  22  in dependence on a bent state of the spring  25 . The distal end  20   f  of tab  20  is first contacted with the distal end  23   f  of spring  23 . 
     In the mating direction F 1  on FIG. 1, the distal end  20   f  of tab  20  is displaced from the distal end  19   a  at a displacement S 1  of substantially zero. If the distal end  20   f  is positioned at an opposite side to the male terminal body  18  relative to the distal end  19   a,  the displacement S 1  is positive. If the end  20   f  is positioned at an identical side with the male terminal body  18  relative to the end  19   a,  the displacement S 1  is negative. 
     On the other hand, in the mating direction F 1 , the distal end  23   f  of spring  23  is displaced from the proximal end  25   a  at a positive displacement S 2 . If the end  23   f  is positioned at an opposite side to the female terminal body  22  relative to the proximal end  25   a,  the displacement S 2  is positive. If the distal end  23   f  is positioned at an identical side with the female terminal body  22  relative to the proximal end  25   a,  the displacement S 2  is negative. 
     The embodiment requires that a relationship of S 1  and S 2  is S 1 +S 2 &gt;0. If the relationship of them is S 1 +S 2 ≦0, the distal end  19   a  is contacted with the proximal end  25   a  earlier or at an identical time. 
     In the connector  10  of the constitution, when mating the female connector  11  and male connector  12 , the protrusion  19 , protruding into the hood part  13  of the female housing  14 , passes through the guide hole  16 B of the front wall  16 A in the male housing  16 . At this time, the spring  23 , as extending forward beyond the front end  22   f  of the female terminal body  22 , contacts with tab  20  before the protrusion  19  and the spring  25  contact. Between the spring  23  and the tab  20 , an arc discharge occurs, and when the protrusion  19  and the spring  25  as original contact parts contact, arc discharge does not generate, so that the protrusion  19  and the spring  25  are prevented from deterioration and damage. Even when the spring  23  and the tab  20  are subjected to deterioration and damage due to an arc discharge, they are not original contact parts, and occurrence of the deterioration causes no problem. 
     In the embodiment, respective one of the male terminal  15  and the female terminal  17  is formed integrally with respective one of the spring  23  and the tab  20  as dummy contacts, and the connector has a contact protecting structure only by mounting the connecting terminals to the housings. Thus, the connector assembly is improved in durability and reliability. 
     Although the invention has been described above by reference to certain embodiments of the invention, the invention is not limited to the embodiments described above. Modifications and variations of the embodiments described above will occur to those skilled in the art, in light of the above teachings. For example, though the above-described embodiment has the spring  23  extending forward beyond the female terminal body  22 , another embodiment is composed such that the spring  23  may be provided to a side part of the terminal body  22  not to extend forward beyond the front end  22   a  of the body  22  and the tab  20  of the other male terminal  15  may extend forward beyond the protrusion  19  as shown on FIG. 4, and the same function and benefit is obtained. In this case, the displacement S 1  is positive, and the displacement S 2  is substantially zero, so that the sum of the displacements S 1  and S 2  is positive. As shown on FIG. 5, the end  23   f  of the spring  23  may be displaced from the proximal end  25   a  on an opposite side to the female terminal body  22  and the distal end  20   f  of the tab  20  may be displaced from the distal end  19   a  of protrusion  19  on an identical side with the male terminal body  18 . The displacement S 1  is negative and the displacement S 2  is positive, so that this requires that the absolute value of S 2  is greater than one of S 1 . 
     Another embodiment is composed such that one of the female and male terminals  15 ,  17  may be formed with a dummy spring which extends forward to contact with a side part of the other terminal. 
     The scope of the invention is defined with reference to the following claims.