Patent Publication Number: US-6666730-B2

Title: Electric connector, with contact positioning elements

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to an electric connector and, more particularly, to an electric connector used in wiring harnesses aboard vehicles. 
     DESCRIPTION OF THE PRIOR ART 
     An electric connector normally comprises a plastic material connector body having a plurality of housings in which respective electrical contacts are inserted. In many types of connectors, the contacts are clipped into the respective housings. 
     One of the most frequent causes of failure in electrical systems aboard vehicles derives from the imperfect fastening of the contacts in the housings on the connector body. Often a connector with an imperfectly fastened contact will pass the initial electric test. Resultantly, this contact may later interrupt the electric connection with a similar contact in working conditions due to movements generated by vibrations, thermal dilatation, etc. For this reason, after assembly of the contacts in the connector body, it is often necessary to check that the contacts are correctly arranged in the respective housings. 
     A traditional way of testing the correct assembly of the contacts consists in forming small indented portions on the contacts. When the contacts are correctly fitted in the respective housings, the indented portions are arranged to correspond with a passing opening formed in the connector body. Correct assembly of the contacts is tested by coupling the connector with a test device equipped with a projecting portion that is inserted in the passing opening in the connector body. The test device is constructed so that if at least one of the contacts is not correctly arranged in the housing, an interference occurs preventing the reciprocal coupling of the connector and the test device. 
     A problem associated with the described test method is that test reliability depends solely on the individual carrying out the test, because it is not possible to know whether the finished connector has passed the test or not by mere examination. It is therefore desirable to develop a connector that overcomes the aforesaid problem. 
     SUMMARY OF THE INVENTION 
     The invention relates to an electric connector for use in the electric connection between the electric system of a vehicle and the electric devices and controls arranged on the steering wheel of the vehicle. The connector comprises a first connector body and a second connector body. The first connector body having a first housing, a first opening, and a first projecting portion. The second connector body having a second housing, a second opening, and a second projecting portion. A plurality of contacts having indented portions such that when the contacts are correctly inserted into the first and second housings, the indented portions correspond with the first and second openings. As a result, when the second connector body is received in the first connector body the first projecting portion is received in the second opening and the second projecting portion is received in the first opening to reciprocally couple the first and second connector bodies. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described by way of example with reference to the accompanying figures wherein: 
     FIG. 1 is a perspective front side view of a connector according to the present invention. 
     FIG. 2 is a perspective rear side view of the connector in FIG.  1 . 
     FIG. 3 is a cross-sectional view taken along line  3 — 3  in FIG. 1, illustrating the connector in an assembled configuration. 
     FIG. 4 is a cross-sectional view taken along line  3 — 3  in FIG. 1, illustrating the two components of the connector in a released condition. 
     FIG. 5 is a cross-sectional view taken along line  5 — 5  in FIG.  3 . 
     FIG. 6 is a cross-sectional view taken along line  3 — 3  in FIG. 1, illustrating a condition where the contact is not arranged properly. 
     FIG. 7 is a cross-sectional view taken along line  7 — 7  in FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Shown in FIGS. 1 and 2 is an electric connector  10  comprising a first connector body  12  and a second connector body  14 . The first connector body  12  has substantially the shape of a parallelepiped enclosure, open on two sides, for receipt of the second connector body  14 . The first and second connector bodies  12 ,  14  are both made of injection moulded plastic material and have contact housings  16 ,  18  for receiving electric contacts  22 . In the embodiment illustrated for the purpose of example in the drawings, the first connector body  12  has four contact housings  16 . The second connector body  14  has eight contact housings  18  arranged in two parallel rows, each formed with four contact housings  18 . 
     Each contact  22  has a portion  24  that is crimped onto an isolating sheath of an electric conductor  26 . Each contact  22  has, on a lateral side, an indented portion  28  and a clip-on engagement element  30  that engages a hole  32  in the first and second connector bodies  12 ,  14  to anchor each contact  22  to the respective housing  16 ,  18 . 
     The second connector body  14  has a pair of slots  34  formed on the lateral sides  36  and arranged over the respective array of the holes  32 . Each of the slots  34  communicates with the adjacent housings  18 . The slots  34  are arranged so that, if the contacts  22  are correctly positioned and engaged in the respective housings  18 , the indented portion  28  of each contact  22  corresponds to the slot  34 . Conversely, if one of the contacts  22  is not correctly engaged in the respective housings  18 , a part of the contact  22  that is not indented, would correspond to the slot  34 . 
     The first connector body  12  has a similar slot  38 , partially visible in FIG.  1 . The slot  38  communicates with the housings  16  and the contacts  22  such that when the contacts  22  are correctly inserted in the housings  16 , the contacts  22  are positioned with the indented portion  28  corresponding to the slot  38 . 
     The first connector body  12  has a pair of parallel sides  40 , defining the sides of the enclosure that receive the second connector body  14 . When the second connector body  14  is received in the first connector body  12 , the lateral sides  36  of the second connector body  14  are in contact with the internal surfaces of the parallel sides  40 . Each of the parallel sides  40  of the first connector body  12  has a rib  42  that projects inwards and is arranged for insertion in the corresponding slot  34  when the first and second connector bodies  12 ,  14  are coupled. 
     The second connector body  14  has a rib  44  that projects from a front side  46  and is perpendicular to the lateral sides  36  on which the slots  34  are formed. The rib  44  is received in the corresponding slot  38  when the first and second connector bodies  12 ,  14  are coupled. 
     Shown in FIGS. 3 and 4, when the contacts  22  are correctly engaged in the respective housings  16 ,  18  nothing can obstruct the engagement of the ribs  42  in the slots  34  and the engagement of the rib  44  in the slot  38 . Consequently, when the second connector body  14  is inserted in the first connector body  12 , the first and second connector bodies  12 ,  14  are coupled to form the complete connector  10  shown in FIG.  3 . The first and second connector bodies  12 ,  14  are equipped with holes  46 ,  48  on the respective bottom sides. The holes  46 ,  48  are respectively aligned when the first and second connector bodies  12 ,  14  are correctly coupled. The simple fact that the first and second connector bodies  12 ,  14  are correctly engaged indicates that the contacts  22  are correctly fastened in the housings  16 ,  18 . Consequently, a test is not required to verify correct positioning and fastening of the contacts  22 . 
     FIGS. 6 and 7 illustrate an example in which two contacts  22  are not correctly fastened in the respective housings  18 . As shown in FIG. 7, the non-indented part of the contacts  22  obstructs the insertion of the ribs  42  inside the slots  34  and the ribs  42  come into contact with the side surface of the contacts  22 . In FIG. 6, the first and second connector bodies  12 ,  14  are not correctly coupled. Because part of the second connector body  14  projects out from the first connector body  12 , the holes  46 ,  48 , therefore, are not aligned. In this condition, the dimensions of the connector  10  make fitting in a complementary housing impossible, clearly demonstrating that the connector  10  was not correctly assembled. The same situation occurs when one of the contacts  22  is not correctly fastened in one of the housings  16  of the first connector body  12 . The only difference being that the rib  44  interferes with the non-indented part of the contact  22  that is not correctly positioned. 
     Naturally, numerous changes can be implemented to the construction and forms of embodiment of the invention herein described, all comprised within the context of the concept characterising this invention, as defined by the following claims.