Patent Application
20060264119
1. Field of the Invention
The present invention generally relates to electrical connectors and, more particularly, relates to an electrical connector assembly for connection to a fuel injector on an engine of a motor vehicle.
2. Description of Related Art
Electrical connectors are known in the art for various purposes. One type of connector is a fuel injector connector, which is provided inside of an engine compartment to connect electrical wires from a fuel injector controller to a fuel injector or actuator associated with the fuel injector. A fuel injector connector must make and retain a secure and reliable electrical connection amidst vibrations and movements caused by an operating engine and moving motor vehicle, as well as the heat and pressure of an internal combustion engine. The difficulty of making a secure and reliable connection is magnified in heavy transport and diesel engine applications such as truck, bus, construction, etc. vehicles.
In the prior art, one common way of making an electrical connection is by use of stud terminals on the fuel injector (or actuator) that engage ring or spade terminals on the electrical wires. The ring or spade terminals are fitted over the stud terminals and capped by stud fasteners or nuts. Torque is applied to the stud fasteners to secure the connection. A special tool is typically required for this operation. This method of making the connection has several disadvantages. Multiple parts and significant time and effort are required to make the connection. The stud fasteners may be dropped and lost during assembly, and may break off after a period of operation.
Other prior art connectors use a mating receptacle and plug pair to complete an electrical connection. The security and reliability of such a connection is dependent on the fit between the receptacle and plug. If the fit is too loose, the plug may move inside or fall out of the receptacle in response to engine and vehicle vibration and movement. If the fit is too tight, the heat and pressure on the receptacle and plug may lead to deformation and failure of the connection.
The present invention provides a fuel injector connector that is secure, reliable, simple-to-assemble and capable of withstanding the vibrations and other environmental factors associated with diesel engines and heavy transport applications. It is a mating receptacle and plug configuration, having a tight fit with loads applied in lateral and vertical directions. A key and keyway ensure proper alignment and provide further limitation of movement, and an external latch captures the fully inserted plug.
In one embodiment of the invention, an electrical connector assembly is provided. The assembly includes a plug with side channels within which socket contacts at a terminal end of an electrical wire are received. The plug also includes first load elements that place a first load on the socket contacts or electrical wire. The assembly also includes a receptacle having pin terminals configured to mate with the socket contacts. Second load elements are formed in the receptacle and aligned with the side channels of the plug to place a second load on the socket contacts.
In another embodiment of the invention, an electrical connector assembly for a fuel injector is provided. A plug has side channels within which socket contacts at a terminal end of an electrical wire are snap fit. Strain relief wedges are formed at a trailing end of the plug. Contact between the strain relief wedges and inner surfaces of the receptacle forces the strain relief wedges away from the receptacle and applies a vertical load to the socket contacts or electrical wire. The plug also includes a key. A receptacle with pin terminals is configured to mate with the socket contacts of the plug. Side loading wedges protrude from inner side surfaces of the receptacle and press against and place a lateral load on the socket contacts. A keyway formed in the receptacle receives the key of the plug to ensure proper insertion and limit movement of the plug. A latch is attached to the receptacle and moveable between an open position to allow insertion of the plug and a closed position to capture the inserted plug.
Another embodiment of the invention is an electrical connector assembly for use in an engine compartment of a heavy transport vehicle. The assembly has a mating plug and receptacle configuration and comprises first vibration-resistant means for creating a compressive force between the plug and the receptacle in a first direction, and second vibration-resistant means for creating a compressive force between the plug and the receptacle in a second direction.
Other features and advantages of the invention will be apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, various features of embodiments of the invention.
Reference will now be made to the drawings wherein like numerals refer to like parts throughout.
A first embodiment of a fuel injector connector 10 according to the present invention is illustrated in
Plug 14 is formed with side openings or channels 20 formed to securely seat an electrical conductor, such as a socket contact 24 (FIGS. 3(a)-(b)). As is known to those of skill in the art, a socket contact is a female-type conductive element that receives a terminal end of a wire at one end 15, and mates with a pin male-type contact at another end 25. In use, socket contact 24 is typically crimped between socket contact end 15 and flange 23 around the bare or stripped portion of the electrical wire to establish a mutual flow of metal, as well as around the insulated portion of the wire adjacent end 15. When in mating engagement within receptacle 12, the mating ends 25 of socket contacts 24 receive and form an electrical connection with pin terminals 26 protruding from a rear inner wall 28 of receptacle 12. Pin terminals 26, when in use, are in electrical communication with another component such as the actuator of a fuel injector.
Socket contacts 24 are preferably snap fit within channels 20 for a tight, secure fit. In one embodiment, exterior flange 23 formed on socket contact 24 fits within a corresponding annular recess 21 in channel 20 to ensure proper orientation and positioning of sockets 24 in channels 20. Thus, assembly of socket contacts 24 and plug 14 is a simple procedure requiring no tools and may be verified by a visual check.
Plug 14 may be formed with a key 16 that engages and moves within a mating keyway 18 formed in receptacle 12 to ensure that plug 14 is oriented and inserted properly into receptacle 12. Key 16 and keyway 18 also serve to limit movement and rotation of plug 14 relative to receptacle 12. In one embodiment, key 16 is formed on an upper surface at the leading end 41 of plug 14, while keyway 18 is formed in an upper, inner surface of receptacle 12. It should be understood, however, that key 16 and keyway 18 could be disposed in alternative configurations. Key 16 could be located on a bottom, inner surface of receptacle 12, for example, with a keyway 18 formed on a bottom surface of plug 14.
As best seen in
In addition to lateral loading means in the form of side wedges 22, connector 10 includes vertical loading means in the form of strain relief wedges 40. Strain relief wedges 40 are formed in plug 14 and are configured to place a vertical load or compressive force on socket contacts 24 and the electrical wire held therein. In one embodiment, strain relief wedges 40 are formed on a lower surface at the trailing end 42 of plug 14 (i.e. the end of plug 14 opposite the leading end 41 that engages pin terminals 26), aligned with channels 20. Strain relief wedges 40 protrude slightly from the lower surface of plug 14 so that, when plug 14 is fully inserted into receptacle 12, contact between strain relief wedges 40 and the inner surfaces of receptacle 12 forces strain relief wedges 40 away from receptacle 12 and thereby constricts channel 20 at the trailing end. When a socket contact 24 is properly oriented and seated within channel 20, strain relief wedges 40 apply a load to the socket contact insulation crimp and wire insulation. Contacts 24 and the wires and insulation crimped therein are restrained along a vertical axis. Thus, strain relief wedges 40 prevent movement of the electrical wire and insulation within socket contact 24, and also relieve the strain on and prevent damage to the conductive crimp formed directly between the socket contact and bare electrical wire adjacent mating end 25 of contact 24.
As is best seen in
In one embodiment, a wire bail or latch 30 is attached and rotatable about the outside of receptacle 12 at pivots 32. Bail 30 is movable between an open position, illustrated in
Thus, connector 10 provides hoop-style loading about both the vertical and horizontal axes with a result of zero movement of the plug relative to the receptacle. Superior ability to withstand vibration is provided. In one test, a connector according to the present invention withstood 60G vibration for eight hours continuous. The connector design is robust and has minimal parts and no complicated connective mechanisms. No special assembly tools are required.
An alternative embodiment of the invention is illustrated in
Another embodiment of the invention is illustrated in
The description above refers to particular embodiments of the present invention and is intended to be illustrative rather than restrictive. While the connector is described in conjunction with a fuel injector, for example, the inventive connector structure may be appropriate in other applications where a tight and vibration-resistant connection is needed. Modification to the described embodiments may be made without departing from the spirit and scope of the invention as defined by the appended claims.
