Electrical connection for fuel injectors

Abstract: An electrical connection arrangement for a fuel injector (20) includes an electrical interface (24) that is supported by the fuel injector body portion (22). The electrical interface preferably includes at least one deformable connector member (26). During assembly, the deformable connector member is manipulated to piece through an insulation layer on a conductor and make an electrical connection with a conductive portion of the conductor. In one example, the connector members are crimped into position to provide an electrical coupling and a physical connection between the interface and the associated conductor. The preferred conductor is a flex cable.

Description: FIELD OF THE INVENTION This invention generally relates to fuel injectors for use with internal combustion engines. More particularly, this invention relates to an electrical connection arrangement for such fuel injectors. BACKGROUND OF THE INVENTION Fuel injectors are typically included as part of the arrangement for providing fuel to an internal combustion engine. Fuel injectors take a variety of forms but typically include at least some electronic components that require electrical power and/or signals for proper operation. Typical arrangements include wire harnesses and standard connectors for coupling the fuel injector components to a power source and other control devices on the vehicle. There are a variety of problems associated with the conventional connection methods used for fuel injectors. Typical connectors include a plurality of male pins associated with the fuel injector and a cooperating set of female pins associated with a connector. The connector typically has an outer shell which facilitates making the connection. During assembly, however, it is not uncommon for some of the male or female pin portions to become bent or distorted. The typical connector housing shields these pins from view so that visual inspection of a proper connection is not possible. Additionally, conventional connection arrangements do not always provide a secure connection over time. US 4570601 discloses a fuel injector having the features of the precharacterising clause of the claims. The arrangement requires ends of conductors to be provided with through-holes which engage an internal claw to prevent retraction. OBJECT TO THE INVENTION The present invention seeks to provide an improved electrical connection for fuel injectors. SUMMARY OF THE INVENTION According to the invention there is provided a fuel injector assembly, comprising: a body portion that houses fuel injector components; an electrical connection portion supported by the body portion; and characterized by at least one deformable connector member supported on the interface portion, the deformable connector member having at least one edge that is adapted to penetrate an insulation covering on an electrical conductor to thereby electrically couple the connector portion to the electrical conductor when the deformable connector is deformed. According to a second aspect of the invention there is provided a method of making an electrically conductive connection between an electrical connector portion on a fuel injector that has at least one deformable connector member and an electrical conductor characterized by, comprising the steps of: positioning a portion of the conductor near the deformable connector member; and deforming the deformable connector member to pierce an insulation layer of the electrical conductor to establish an electrically conductive connection between the electrical interface and the conductive core of the electrical conductor. In general terms, therefore, the invention provides a fuel injector assembly that includes a body portion that houses the fuel injector components. An electrical interface portion is supported by the body portion. At least one deformable connector member is supported on the interface portion. The deformable connector member has at least one edge that is adapted to penetrate an insulation covering on an electrical conductor to thereby electrically couple the connector portion to the electrical conductor. In the preferred arrangement, the conductor is a flex cable and there are a plurality of deformable connector members that are crimped into connection with the conductive part of the flex cable. This invention can thus provide an improved connection arrangement that facilitates more secure electrical and physical connections for coupling a fuel injector to other electrical components on a vehicle. This invention can also provide one or more of the advantages of a more secure connection, visual inspection capabilities, simplified manufacturing procedures and material cost savings. The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 schematically illustrates a fuel injector assembly designed according to this invention. Figure 2 is a partial, perspective, exploded view of selected components of the embodiment of Figure 1. Figure 3 illustrates the components of Figure 2 in an assembled condition. Figure 4 is a cross sectional view taken along the lines 4-4 in Figure 3. Figure 5 illustrates another example embodiment from a cross sectional view. Figure 6 schematically illustrates machinery for making an electrical connection according to this invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT There will now be described, by way of example only, the best mode contemplated by the inventor for carrying out the invention. In the following description, numerous specific details are set out in order to provide a complete understanding of the present invention. It will be apparent, however, to those skilled in the art, that the present invention may be set into practice with variations of the specific. A fuel injector assembly 20 includes a generally conventional fuel injector body portion 22. An electrical interface 24 includes at least one connector member 26 to facilitate electrically coupling selected components of the fuel injector to other devices on a vehicle, such as an electronic controller and a power source, for example. An electrical conductor 28 permits communication of such electrical signals or power as needed. The electrical connection interface 24 preferably includes a support portion 30 that receives and supports a portion of the conductor 28 during an assembly process. Once the conductor 28 is positioned relative to the interface 24, the connector members 26 preferably are deformed so that at least one portion of each connector member penetrates through an insulation layer 32 on the conductor 28 and forms an electrical coupling with a conductive portion 34 of the conductor 28. In the illustrated example, the connector members 26 are barbs with pointed edges that pierce through the insulation layer 32 and engage the conductive portion 34. In the illustrated arrangement, it is preferred to crimp the connector members 26 into the position shown in Figure 4, for example, where a secure physical and electrical connection has been made between the interface 24 and the conductor 28. Once an appropriate connection has been made, it is preferred to include a covering over at least a portion of the connecting interface 24 and an associated portion of the conductor 28. Figure 5 illustrates an example covering 50, which preferably covers over the entire connecting interface 24 and an associated portion of the conductor 28. In one example, the covering 50 is molded plastic that is applied after the appropriate electrical connection has been made. In another example, the covering 50 is a seal that is applied to not only cover over the connecting interface 24 but also to provide a seal along the associated region of the fuel injector body 22 to prevent any contaminants from entering an opening in the body portion 22 adjacent the interface 24. Other example coverings 50 include foam or silicone type materials. The purpose of the covering 50 is to prevent wear or deterioration over time due to environmental exposure. Figure 6 schematically illustrates machinery 60 for holding a fuel injector in place during the assembly procedure according to this invention. Crimping members 62 preferably move as shown by the arrow 64 into position to deform the connector portions 26 into a position where a proper electrical and physical coupling is made. In the illustrated example, the crimping members 62 crimp the barb portions 26 into a position as shown in Figure 4, for example. The preceding description is exemplary rather than limiting in nature. For example, a single conductor with a plurality of connector members has been illustrated. Of course, this invention is applicable to fuel injector arrangements having multiple electrical conductors that are coupled with fuel injector components. Each conductor member may include a plurality of connector members, but at least one is preferred.

Claims: A fuel injector assembly (20), comprising: a body portion (22) that houses fuel injector components; an electrical connection portion (24) supported by the body portion (22); and at least one deformable connector member (26) supported on the connection portion (24), characterized by the deformable connector member (26) having at least one edge that is adapted to penetrate an insulation (32) covering on an electrical conductor (28) to thereby electrically couple the connection portion (24) to the electrical conductor when the deformable connector (26) is deformed. The assembly of claim 1, including a plurality of connector members (26), each comprising a barb of deformable metal material. The assembly according to claim 1 or 2, wherein the electrical connection portion (24) at least partially extends outwardly and away from the body portion and the deformable connector member is outside of the body portion. The assembly of claim 3, including a plurality of connector members, each comprising a barb of flexible metal material. The assembly according to claim 3 or 4, including a securing member placed over the conductor and the connector member. The assembly of claim 5, wherein the securing member comprises plastic that is molded over the conductor and the connector member. The assembly of claim 5, wherein the securing member comprises a seal. The assembly of claim 5, wherein the securing member comprises at least one material selected from the group consisting of plastic, foam or silicone. The assembly of claim 3, wherein the conductor comprises a flexible conductor cable. The assembly of claim 3, including a plurality of conductors and a corresponding plurality of deformable connector members. A method of making an electrically conductive connection between an electrical connector portion (24) on a fuel injector (20) that has at least one deformable connector member (26) and an electrical conductor (28), characterized by the steps of: positioning a portion of the conductor near the deformable connector member; and deforming the deformable connector member to pierce an insultation layer of the electrical conductor to establish an electrically conductive connection between the connector portion (24) and the conductive core of the electrical conductor 28. The method of claim 11, including crimping the deformable member onto the conductor. The method of claim 11, including covering the deformable connector member and an associated portion of the conductor after performing the deforming step. The method of claim 13, including molding a plastic material onto the connector member and the associated portion of the conductor. The method of claim 13, including placing a seal over the connector member and the associated portion of the conductor.

Inventors: KARELL ERIK K, KARELL, ERIK K.
Applicants: SIEMENS VDO AUTOMOTIVE INC, SIEMENS VDO AUTOMOTIVE INC.
Application year: 2001
Main classification: F02D41
IPC codes: H01R4, F02M51, F02D41