Abstract:
A replacement kit for replacing an electrical device coupled to a vehicle via a plurality of vehicle lead wires. The replacement kit includes a replacement electrical device, a plurality of lead wires extending from the replacement electrical device, and a housing assembly for protecting a spliced connection formed with the lead wires to create an electrical connection between the electrical device and the vehicle. The housing assembly includes a base having a plurality of individually isolated bores extending therethrough. Each bore is capable of housing a spliced connection of a respective vehicle lead wire and a respective replacement electrical device lead wire, and each bore has therein a plurality of seal rings to form a substantially water-tight seal around the associated portion of the spliced connection. The housing assembly also includes a cap secured to the base. Preferably, the electrical device and the replacement electrical device are oxygen sensors.

Description:
RELATED APPLICATIONS 
     This application claims priority to provisional application Ser. No. 60/242,490, filed on Oct. 23, 2000. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to electrical connections, and more particularly to methods and devices for forming electrical connections on automobiles. 
     BACKGROUND OF THE INVENTION 
     Automotive electrical systems include numerous electrical connections formed with various electronic modules and/or sensors on the automobile. One example of such an electrical connection is the connection formed between an exhaust gas oxygen sensor and the engine control unit (ECU). Exhaust gas oxygen sensors are mounted in the exhaust system and measure the oxygen content in the exhaust gases of an internal combustion engine. The electronic signal generated by the oxygen sensor is interpreted by the ECU to vary the air/fuel ratio of the mixture supplied to the engine. 
     Factory-installed oxygen sensors are electrically connected to the ECU using some form of a connector. Wire leads extending from the oxygen sensor terminate in a sensor-end connector, which can be male or female. The sensor-end connector is connected to a mating vehicle-end connector that is wired to the ECU. The two mating halves of the connector are usually made of plastic and provide a suitable watertight mechanical and electrical connection. 
     Each automobile manufacturer specifies a unique set of mating connectors to mate the oxygen sensor to the vehicle harness. Suppliers of the factory-installed oxygen sensors must provide oxygen sensor assemblies with this manufacturer-specified connector. While this compatibility requirement is to be expected when supplying original oxygen sensors to the vehicle manufacturers, it creates complexity when competing in the aftermarket (i.e., supplying replacement oxygen sensors). 
     Small repair shops and retail part suppliers typically do not have the inventory capacity to stock replacement oxygen sensor assemblies for every make and model of vehicle. If the required oxygen sensor assembly is not in stock, the replacement sensor assembly must be obtained from Original Equipment Manufacturers (OEM&#39;s), who will also not likely have the sensor in stock, and will need to order the sensor from their distribution center. 
     SUMMARY OF THE INVENTION 
     The present invention removes the need for the OEM&#39;s to supply the aftermarket. By facilitating a suitable mode of connection between a replacement oxygen sensor and the OEM connector, market complexity is greatly reduced. This reduced complexity benefits the consumer. The invention provides a replacement oxygen sensor that can be spliced to the existing oxygen sensor wiring harness irrespective of the design of the OEM connector. 
     Commonly used splicing techniques are also problematic. The original electrical and mechanical connection provided by the connector offers a reliable, watertight connection that can withstand the harsh environment of the under-carriage and under-hood of a vehicle. The new splice must also be well protected. Heat shrink tubing may not provide the long-term robustness required to prevent unwanted intrusions into the oxygen sensor. 
     The present invention addresses the compatibility issues associated with aftermarket oxygen sensor installation, and the resulting inadequacy of commonly used splicing techniques by providing a weather-resistant housing assembly for protecting a spliced electrical connection. The housing assembly includes a base having a plurality of individually isolated bores extending therethrough. Each bore is capable of housing a portion of the spliced connection and each bore has therein at least one seal ring to form a substantially water-tight seal around a portion of the spliced connection. The housing assembly also includes a cap secured to the base. The cap preferably includes a plurality of lead exit apertures. Each lead exit aperture corresponds to one of the respective bores. 
     In one aspect of the invention, the base has four sides and each of the four sides includes a projection. The cap also has four sides and two of the four sides of the cap include a resilient locking tab configured to engage one of the projections on the base. The cap can be secured to the base such that any one of the locking tabs engages any one of the projections. Preferably, the cap further includes a slot in each of the two sides that do not include the resilient locking tab. The slots receive the projections not engaged by the resilient locking tabs. 
     The invention also provides a universal aftermarket oxygen sensor replacement kit. The kit includes a replacement electrical device, a plurality of lead wires extending from the replacement electrical device, and a housing assembly for protecting a spliced connection formed with the vehicle lead wires and the replacement electrical device lead wires to create an electrical connection between the replacement electrical device and the vehicle. In a preferred embodiment, the replacement electrical device is an oxygen sensor. 
     The housing assembly includes a base having a plurality of individually isolated bores extending therethrough. Each bore is capable of housing a spliced connection of a respective vehicle lead wire and a respective replacement electrical device lead wire. The housing assembly also includes a plurality of seal rings. At least one seal ring is receivable in each bore to form a substantially water-tight seal around a portion of the spliced connection. The housing assembly further includes a cap that can be secured to the base. 
     The invention also provides a method of replacing an electronic device assembly on a vehicle. The electronic device assembly includes an electronic device, a device-end connector connected to a vehicle wire harness at a vehicle-end connector, and a plurality of lead wires extending between the electronic device and the device-end connector. 
     The method includes cutting the plurality of lead wires between the device-end connector and the electronic device, sliding a first portion of a splice housing onto the cut plurality of lead wires toward the device-end connector, providing a replacement electronic device having a plurality of replacement lead wires extending from the replacement electronic device, sliding a second portion of the splice housing onto the replacement lead wires toward the replacement electronic device, splicing the cut plurality of lead wires to the respective replacement lead wires, and sliding the first and second portions of the splice housing together over the spliced lead wires to connect the first and second portions of the splice housing and to substantially enclose the spliced lead wires. 
     In one aspect of the invention, splicing the cut plurality of lead wires to the respective replacement lead wires includes using splice connectors. In another aspect of the invention, sliding the first and second portions of the splice housing together includes isolating the respective spliced lead wires from one another in individually isolated bores extending through one of the first and the second portions of the splice housing. 
     Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims, and drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a typical, factory-installed oxygen sensor arrangement for a vehicle. 
     FIG. 2 is a perspective view showing an oxygen sensor replacement kit embodying the invention, replacing the factory-installed oxygen sensor of FIG.  1 . 
     FIG. 3 is an exploded perspective view of the oxygen sensor replacement kit. 
     FIG. 4 is a section view illustrating the splice and the protective housing surrounding the splice. 
     FIG. 5 is an end view of the base of the protective housing of FIG.  3 . 
     FIG. 6 is an end view of the cap of the protective housing of FIG.  3 . 
     FIGS. 7 and 8 illustrate the steps of making the spliced connection when installing the oxygen sensor replacement kit of FIG.  2 . 
    
    
     Before one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 illustrates a typical connection arrangement for a factory-installed, original oxygen sensor assembly  10 . The oxygen sensor assembly  10  includes an oxygen sensor  14  that can be mounted in the vehicle&#39;s exhaust system, indicated generally at  15 . While shown as being threaded directly into the vehicle&#39;s exhaust system  15 , the sensor may also be mounted via a flange (not shown) attached to the oxygen sensor. The oxygen sensor  14  is mounted such that a portion of the sensor is positioned within the stream of exhaust gases  16  (indicated by the arrows in FIG.  1 ). Insulated sensor leads  18  extend from the oxygen sensor  14 , and a sensor-end connector  22  is connected to the ends of the sensor leads  18 . The number of sensor leads  18  can vary depending upon the particular oxygen sensor  14  being used. Typically, there are either three or four sensor leads  18 . A flexible sleeve  24  can be used to contain and protect the sensor leads  18 . 
     The oxygen sensor assembly  10  is electrically connected to the vehicle&#39;s engine control unit (ECU) (not shown) via a vehicle-end connector  26 . Insulated vehicle-end leads  30  extend from the ECU and terminate at the vehicle-end connector  26 . 
     As described above in the background of the invention, each vehicle manufacturer specifies the vehicle and the respective oxygen sensor connectors  22  and  26 . The suppliers who provide the oxygen sensor assembly  10  to the manufacturers must design the oxygen sensor assembly  10  to include this customer-specified connector. The connectors  22 ,  26  provide a mechanical and electrical connection between the oxygen sensor  14  and the ECU that is suitably protected from the environment. Because the present invention operates without regard to the specific connector  22 ,  26  configurations, the specific configuration of the sensor-end connector  22  and the vehicle-end connector  26  shown in FIG. 1 will not be described further. 
     As shown in FIGS. 2-7, the invention provides a universal oxygen sensor assembly replacement kit  34  that is particularly suitable for sale in the aftermarket. The replacement kit  34  replaces pre-existing factory-installed oxygen sensor assemblies, regardless of the specific configuration of the vehicle-end connector  26  and sensor-end connector  22 . 
     As best seen in FIG. 3, the replacement kit  34  includes an oxygen sensor  38  having the associated insulated sensor leads  42  and flexible sleeve  44  (see FIG.  2 ). Again, the number of leads  42  can vary, with three or four leads  42  being the most common. Unlike with the oxygen sensor assembly  10 , the sensor leads  42  do not terminate at a sensor-end connector. Rather, each of the sensor leads  42  terminates at a free end  46  (see FIG.  7 ). The insulation on the leads  42  can extend to the free ends  46  or can be partially removed to expose respective portions of the conductive wire in preparation for splicing. 
     The replacement kit  34  preferably also includes splice supplies  50  for splicing the free ends  46  to the original sensor leads  18  as will be described below. In the illustrated embodiment, the splice supplies  50  are in the form of four individual POSI-LOCK no-crimp connectors  54 . The connectors  54  are available from Swenco Products located in Poplar Bluff, Mo., and are the subject of U.S. Pat. Nos. 5,228,875, 5,695,369, 5,868,589, and other pending applications. FIG. 4 illustrates a completed splice, generally indicated as  56 . The splice supplies  50  can alternatively be any other suitable devices for splicing, including various butt connectors (not shown). Use of such butt connectors may require some additional componentry (not shown). 
     The replacement kit  34  also includes a two-piece protective housing  58  having a base  62  and a cap  66 . The protective housing  58  is assembled over the spliced leads  18  and  42  to capture the splice  56  and to protect the splice  56  from the environment. As best seen in FIGS. 3-5 and  7 - 8 , the base  62  includes a body portion  70  having a splice receiving end  74  (for splices  50  and wire seals  118 ) and a lead exit end  78 . The body portion  70  includes four individually isolated bores  82  extending between the ends  74  and  78 . The bores  82  each have a first diameter that remains substantially constant over the majority of the body portion  70 . 
     Bosses  86  are formed adjacent the end  78 . As shown in FIG. 4, the bores  82  are stepped at the bosses  86  such that inside the bosses  86 , the bores  82  have a second diameter that is slightly smaller than the first diameter. The purpose of the bosses  86  and the reduced second diameter will be described below. The end surfaces of the bosses  86  include (see FIG. 5) lead exit apertures  90  communicating with the respective bores  82 . The apertures  90  each have a diameter that is smaller than both the first and second bore diameters. The apertures  90  provide an exit from the base  62  for the leads  18  or  42 . 
     The base  62  also includes projections  94  on each side of the body portion  70 , adjacent the end  74 . The projections  94  secure the base  62  to the cap  66  as described below. 
     The cap  66  is sized to fit over the end  74  of the base  62  as shown in FIG.  4 . The cap  66  includes two resilient locking tabs  98  spaced 180 degrees from one another on opposing sides of the cap  66 . The tabs  98  include openings  102  for receiving the projections  94 . As the cap  66  is pressed onto the base  62 , the ramped surface of the projections  94  deflects the tabs  98  outward until the projections  94  are completely within the openings  102 , at which point the tabs  98  snap into place over the projections  94 . The remaining two sides of the cap  66  include slots  106  that slidably receive the remaining two projections  94 . The illustrated tab/projection securing method allows the cap  66  to be secured to the base  62  regardless of the respective orientations of the base  62  and the cap  66 . 
     As best seen in FIGS. 4 and 6, the cap  66  also includes bosses  110  having an inner diameter substantially equal to the second diameter described above with respect to the bores  82  and the bosses  86 . The purpose of the bosses  110  will be described below. The end surfaces of the bosses  110  include lead exit apertures  114  communicating with the inside of the bosses  110  and the inside of the cap  66 . The apertures  114  preferably have the same diameter as the apertures  90  and provide an exit from the cap  62  for the leads  18  or  42 . 
     The housing  58  is preferably made from injection molded plastic, but could be made from any other suitable materials. The housing  58  is not limited to the configuration shown in the figures. In particular, the housing  58  could be modified to accommodate fewer or more leads. Additionally, other securing structure could be used to secure the cap  66  to the base  62 . 
     The replacement kit  34  also includes a plurality of seal rings  118  for providing a watertight seal around the splice  56 . The seal rings  118  each include a nose portion  122  and a ribbed portion  126 . A lead receiving hole  130  (see FIG. 3) extends through the center of the seal ring  118 . As best seen in FIGS. 4,  7 , and  8 , a lead  18  or  42  can be inserted into the hole  130 , allowing the seal ring  118  to be slid over the lead  18  or  42  to provide a water-tight fit between the lead  18  or  42  and the seal ring  118 . The nose portion  122  is receivable in the reduced-diameter portion of the bosses  86  or  110 . The ribbed portion  126  includes a plurality of ribs  134  that engage the inside of the body portion  70  in the bore  82  to provide a water-tight seal between the splice  56  and the base  62 . 
     The seal rings  118  are made from any suitable elastomeric material, such as silicon rubber. The replacement kit  34  is shown to include eight seal rings  118 , but fewer or more seal rings  118  can be included, depending on the number of leads  42 . Furthermore, the ribbed portions  126  can include fewer or more than three ribs  134 . Of course, other seal ring configurations can also be used. 
     In FIG. 4, each opposing pair of seal rings  118  is shown to directly abut opposite ends of the connector  54 . It should be noted that the seal rings  118  can also be spaced from the ends of the connector  54  without deviating from the invention. In other words, the seal rings  118  are sized to sealingly engage the bores  82  regardless of whether or not the seal rings  118  directly abut, or are even slightly compressed by engagement with the connectors  54 . This provides added flexibility to use various different types of splice supplies  50 . Of course, compressing the seal rings  118  with the connectors  54  to cause radial expansion of the seal rings  118  can be an additional or an alternative technique to obtain the desired sealing. 
     The method of installing the universal oxygen sensor assembly replacement kit  34  will now be described. First, the original oxygen sensor  14  is removed by cutting the original sensor leads  18  between the oxygen sensor  14  and the sensor-end connector  22 . A sufficient length of sensor lead should remain to facilitate installation of the replacement kit  34 . Next, the housing  58  and the seal rings  118  are installed as shown in FIG.  7 . The base  62  is mounted on the original sensor leads  18  by passing the cut leads through the respective exit apertures  90 . The base  62  can then be slid over the leads  18  toward the sensor-end connector  22 . Next, four of the seal rings  118  are slidably mounted on the leads  18  as shown. 
     The cap  66  is mounted on the leads  42 , which are connected to the replacement sensor  38 . The free ends  46  are passed through the respective exit apertures  114 , and the cap  66  is slid toward the sensor  38 . The four remaining seal rings  118  are slidably mounted on the leads  42  as shown. Of course, the base  62  and the cap  66  can be reversed such that the base  62  is mounted on the leads  42  and the cap is mounted on the leads  18 . The order of the installing the base  62  and the cap  66  can also be reversed. 
     Next, as shown in FIG. 8, the cut ends of the leads  18  and the free ends  46  are spliced together using the connectors  54  or any other suitable splice supplies  50 . Again, the splice  56  can also be formed via welding or soldering. With the splice  56  completed, the base  62  and the cap  66  can be moved together in the direction of the arrows in FIG.  8 . As the base  62  and cap  66  are moved together, the nose portions  122  of the seal rings  118  will become seated in the respective bosses  86 ,  110  and the ribs  134  will engage the inside of the base  62  defining the respective bores  82 . The base  62  and cap  66  are moved together until the tabs  98  snap over the respective projections  94 . The splice  56  creates the electrical connection, and the splice  56  is protected from the environment by the housing  58  and the seal rings  118 . FIG. 2 illustrates the arrangement of the installed universal oxygen sensor assembly replacement kit  34 . 
     The installation method is substantially the same regardless of whether there are three or four sensor leads  42  extending from the new sensor  38 . If only three leads  42  are present, one of the bores  82  will remain empty. Because the bores  82  are isolated from one another inside the body portion  70 , any water entering the empty bore  82  via the corresponding exit apertures  90 ,  114  will not come into contact with the splices  56  in the three remaining bores  82 . Of course, the base  62  of the housing  58  could be modified to include fewer or more than four bores  82 . Such a modification would likely require a corresponding modification to the cap  66 . 
     While the preceding description of the preferred embodiment describes the present invention as being used for connecting an oxygen sensor, it should be understood that the present invention could also be used for any connection requiring a weatherproof splice. The present invention is particularly suitable for electrical connections involving components that require occasional or periodic replacement. The present invention is also well suited for lengthening a wire set that is subjected to a corrosive environment. For example, the present invention would be well suited for lengthening or replacing the electrical lighting connection between a vehicle and a trailer, especially when the trailer is submersible, such as for boats and other watercraft. Replacing other electrical devices, which are connected in a similar arrangement to the oxygen sensor assembly  10 , is also contemplated. 
     Various features of the invention are set forth in the following claims.