Patent Publication Number: US-4225206-A

Title: Electrical connector for electromagnetic fuel injector

Description:
This invention relates generally to electrical connectors and more particularly to an electrical socket connector at the end of insulated conductor wires which comprise electrical terminals housed in a connector body of molded relatively hard plastic. 
     The object of this invention is to provide an electrical socket connector of this type which is especially suitable for making an electric connection to an electrical device such as the electromagnetic fuel injector disclosed in FIGS. 5-9 of U.S. patent application Ser. No. 941,754 filed by James D. Palma on Sept. 13, 1978 for &#34;Electromagnetic Fuel Injector&#34;. 
     This fuel injector has a cover in the form of a circular pole piece 162 which has an upstanding central boss 162b housing a spring adjusting screw 170. The pole piece 162 has a pair of diametrically opposed holes located radially outwardly of the boss 162b through which plastic studs 162a project. Pin terminals 166 connected to the terminal ends of an actuating coil for the electromagnetic fuel injector project from the ends of the plastic studs 162a. 
     The fuel injector is intended for use in a throttle body fuel injection system for a spark ignition internal combustion engine. This application requires an electrical socket connector which provides a sealed electrical connection while being of relatively low profile so as to fit beneath an air cleaner for the throttle body. 
     Consequently a more specific object of the invention is to provide a sealed electrical socket connector of relatively low profile which can be coupled to an electrical device having a pair of upstanding pin terminals located on opposite sides of a central upstanding boss or projection. 
     Another object of this invention is to provide a sealed low profile electrical socket connector which can also be detachably secured to such an electrical device. 
    
    
     Other objects and features of the invention will become apparent to those skilled in the art as the disclosure is made in the following detailed description of a preferred embodiment of the invention as illustrated in the accompanying sheet of drawing in which: 
     FIG. 1 is a longitudinal section of an electrical connector according to this invention, 
     FIGS. 2 and 3 are sections taken substantially along the lines 2--2 and 3--3 of FIG. 1, respectively; and 
     FIG. 4 is an exploded perspective view of the electrical connector shown in FIGS. 1, 2 and 3. 
    
    
     Referring now to the drawings, the electrical socket connector 10 comprises a connector body 12, a pair of pin grip terminals 14 and a seal member 16. 
     The electrical connector 10 is designed for detachable securement to an electrical device 100 having an upstanding central boss 102 flanked by a pair of protruding pin terminals 104 as will hereinafter more fully appear. 
     The connector body 12 is made from a moldable, electrically insulative, relatively hard thermoplastic material such as nylon. The connector body 12 comprises a pair of longitudinal terminal housings 18a and 18b which are connected to each other in a laterally spaced, parallel arrangement by integral bridges 20a and 20b. 
     The terminal housings 18a, 18b respectively define longitudinal terminal receiving cavities 22a, 22b which are closed at the forward end of the connector body 12. The forward portions of the terminal cavities are generally rectangular while the respective rearward portions 24a, 24b are circular and provide rear openings for receiving the pin grip terminals 14. The median portions of the housings 18a and 18b have depending annular sockets 26a and 26b, respectively. The annular sockets 26a and 26b are parallel to each other and define vertical passageways leading into the respective longitudinal terminal cavities 22a and 22b as shown in FIGS. 1 and 2. 
     Each pin grip terminal 14 comprises an elongated, U-shaped, contact having two flat blades 28a and 28b which engage one of the pin terminals 104 across its diameter. The base of the blade 28a is contiguous an attachment portion 28c comprising crimp barrels which attach the pin grip terminal 14 and a seal sleeve 30 to the end of an insulated conductor wire 32. Further details on the manner in which the crimp barrels attach a terminal and seal sleeve to the end of an insulated conductor wire are described in U.S. patent application Ser. No. 912,835 filed by Harold G. Hawkins on June 5, 1978 for an &#34;Assembly for Sealed Electrical Connector&#34;. 
     The base of the blade 28a has two transverse tabs 28d with bent ends which are disposed outside the free end of the blade 28b and restrain its lateral movement away from the blade 28a. The blade 28b has a struck out lock tab 28e which cooperates with internal shoulders in the cavities 22a and 22b to retain a particular pin grip terminal 14 in its respective cavity as shown in FIG. 3. When the pin grip terminals 14 are properly positioned and retained in the cavities 22a and 22b, the circular lips of the seal sleeves 30 engage the wall of the circular cavity portions 24a and 24b and seal the rear openings of the cavities. 
     The connector body 12 includes a secondary lock flap 34 which has a pair of slots 35 and which is connected to the rearward bridge 20b by an integral flexible hinge. After the pin grip terminals 14 are assembled in the cavities 22a and 22b, the secondary lock flap 34 is moved from the open position shown in FIG. 4 to the closed position shown in FIG. 1. In the closed position, the flap 34 is behind the seal sleeves 30 and the insulated conductor wires 32 pass through the slots 35. The slots 35, however, are not wide enough to permit passage of the seal sleeves 30. Thus the closed flap 34 cooperates with the ends of the seal sleeves 30 to provide a secondary lock which prevents the pin grip terminals 14 from being pulled out of the cavities 22a, 22b by the conductor wires 32. The flap 34 has side pieces which cooperate with projections on the connector body 12 to latch the flap in the closed position. The latch is so designed that the secondary lock flap will continue to function even if all material in the hinge area completely separates after the flap is fully closed and latched. 
     The forward bridge 20a is preferably located in the plane of the parallel depending annular sockets 26a and 26b so that the connector body 12 is very rigid in the lateral direction at this location. The forward bridge 20a and annular sockets 26a and 26b are spaced from the forward end of the connector body 12 to accommodate part of a latch mechanism for detachably securing the connector body 12 to the electrical device 100. 
     The latch mechanism takes the form of a pair of integral vertical latch arms 36 and 38 disposed between the terminal housings 18a and 18b. Each of the latch arms is connected to the confronting side walls of each of the terminal housings 18a, 18b by connectors of small cross section which serve as pivots for the vertical latch arms 36 and 38. The latch arms 36, 38 are connected to the terminal housings 18a, 18b forwardly and rearwardly of the bridge 20a respectively and each latch arm projects above and below the terminal housings 18a, 18b. 
     The upper ends of the latch arms 36, 38 have finger grips 40 while the lower ends have hooks 42 which face each other and which move away from each other when the finger grips 40 are squeezed toward each other. 
     The forward bridge 20a is raised so that it acts as a stop which limits the squeezing movement of the finger grips 40 toward each other to prevent the pivots for the latch arms 36, 38 from being overstressed. The top surface of the raised bridge 20a also provides a convenient pad for applying a finger force to the connector body 12 to couple the connector 10 to the electrical device 100. 
     The seal member 16 is molded from an elastomeric material such as an epichlorohydrin compound. The seal member 16 comprises a pair of seal sleeves 44a, 44b which are connected together by an integral saddle 44c at their upper end. The bores of the sleeves 44a, 44b are sized to snugly fit on and seal against the outer surfaces of the sockets 26a, 26b, respectively. Each of the sleeves 44a, 44b has an inward circular sealing lip 44d which is adjacent the lower end of its associated socket and which projects inwardly of the passage of the associated socket for sealing around a plastic stud 106 received in the passage as shown in FIGS. 1 and 2. 
     The saddle 44c is narrow so that it passes between the hooks 42 (in the unstressed position of the latch arms 36, 38 shown in FIG. 1) to facilitate assembling the seal member 16 to the connector body 12. 
     The saddle 44c is also raised so that it fits between the terminal housings 18a and 18b out of the way of the upstanding boss 102 of the electrical device 100. 
     The electrical socket connector 10 is especially suitable for connection to an electrical device, such as a fuel injector indicated generally at 100 in the drawings. The device 100 has a cover which has an upstanding central boss 102 and a pair of pin terminals 104 which project out of studs 106 of plastic or other insulating material. In this particular device, the central boss 102 is used to house an adjusting screw 108 and has an enlarged head 102a which provides an excellent catch member for detachably securing the electrical socket connector 12. The portions of enlarged head 102a near the plastic studs 106 and pin terminals 104, however, have arcuate cutouts 102b to provide room for the seal sleeves 44a and 44b to fit between the boss 102 and the studs 106 when the electrical connector 10 is plugged onto the electrical device 100. 
     I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.