Patent Publication Number: US-7591674-B2

Title: Relay retrofit apparatus having a relay with two different sets of contacts, and method for retrofitting a portion of an electrical system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is a continuation of U.S. application Ser. No. 11/096,977, filed Mar. 31, 2005, now U.S. Pat. No. 7,322,849, which is hereby incorporated herein in its entirety by reference. 

   BACKGROUND OF THE INVENTION 
   Currently, replacing a relay located within a vehicle&#39;s electrical system requires a labor intensive effort on the part of a mechanic. Never is the case truer than when the new relay has a different electrical contact configuration than the original. The vehicle&#39;s socket, which is configured to receive a relay having a specific electrical configuration, is not capable of connecting with a relay having a different contact configuration. Therefore, the mechanic is forced to either replace the socket with one that fits the new relay, or cut the vehicle&#39;s socket out and splice the new relay directly into the vehicle&#39;s electrical system. Either procedure is both time consuming and labor intensive. In addition, each procedure introduces the possibility of human error not subject to routine quality control measures. If the work is performed improperly, particularly if the relay is related to a critical safety system of the vehicle, a dangerous condition may result which could lead to damage to the vehicle and its human occupants. Accordingly, there is a need for a device that can easily replace relays having different electrical contact configurations, and do so with assurance of proper connection of the new relay to the vehicle&#39;s electrical system. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention overcomes the deficiencies of the prior art by providing an apparatus for replacing one relay with a new relay when the two have different electrical contact configurations. 
   Generally described, the invention is directed toward an apparatus comprising a plug having electrical contacts and a relay electrically coupled to the plug, in which the plug and the relay have electrical contacts configured differently from one another. 
   In other embodiments, the apparatus can use wiring to connect the relay with the plug. In addition, in some embodiments, the wiring can be insulated. The apparatus can further comprise a shroud that is attached adjacent the plug wherein the shroud encases at least a portion of the electrical contacts of the plug to provide a weatherproof connection when the plug is inserted into a socket. In one embodiment, the relay has a 75 amp dual pole configuration. 
   In an alternative embodiment, the invention is directed to an apparatus comprising a plug having electrical contacts configured to be inserted into a first socket configured for a first relay, wiring having first ends connected to the electrical contacts of the plug and second ends opposite the first ends, and a connector having electrical contacts connected to the second ends of the wiring, wherein the connector is configured to receive contacts of a second relay having electrical contacts with a different configuration than the electrical contacts of the first relay. 
   In some embodiments, the wiring is insulated while other embodiments include a detachable connector. In one embodiment, the connector is a socket. In yet another embodiment, the apparatus further comprises a shroud attached adjacent the plug. In a different embodiment, the shroud encases at least a portion of the electrical contacts of the plug when the plug is inserted into a first socket. In yet another embodiment, the first and second relays have different amperage ratings. In still another embodiment, the first socket is configured to receive a first relay having a 40 amp single pole configuration and the second relay has a 75 amp dual pole configuration. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
     Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: 
       FIG. 1  shows one embodiment of the relay retrofit apparatus. 
       FIG. 2  shows a 40 amp single pole relay. 
       FIG. 3  shows a close up view of the relay retrofit apparatus of  FIG. 1 . 
       FIG. 4  illustrates a prior art method of attaching a relay to a vehicle&#39;s wiring harness. As shown, the relay is mounted to a vehicle&#39;s brake booster housing. 
       FIG. 5  shows the relay retrofit apparatus of  FIG. 1  installed within a vehicle&#39;s brake system. In this embodiment, the relay retrofit apparatus is plugged into a socket and the relay is mounted to the vehicle&#39;s brake booster assembly. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The present inventions now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the inventions are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. 
   Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. 
   I. Structure of the Relay Retrofit Apparatus 
   A relay retrofit apparatus  10  is formed by electrically coupling a relay  50  having a first electrical contact configuration  60  to a plug  30  having a second electrical contact configuration. The first contact configuration of the relay  50  is different than the second electrical contact configuration of the plug  30 . Provided below is a written description of the elements that comprise the embodiment of the relay retrofit apparatus  10  as shown in  FIG. 1 . 
   The Plug 
   In the embodiment illustrated in  FIG. 1 , one end of the relay retrofit apparatus  10  comprises a plug  30 . In this particular embodiment, the plug includes “male” contact configurations designed to be inserted into an electrical socket. The plug&#39;s contact configuration is identical to the contact configuration  45  of the original relay  35 , shown in  FIG. 2 . In this embodiment, the original relay  35  and the plug  30  of the relay retrofit apparatus  10  comprise a 4 pin, flat contact configuration  45 . In alternative embodiments, the original relay  35  and the plug  30  of the relay retrofit apparatus  10  comprise contact configurations such as the European 7 pin configuration, a 6 way round configuration, or any other contact configuration known in the art. Additionally, other embodiments (not shown) of the relay retrofit apparatus  10  can be equipped with plugs  30  having a female contact configuration. In the embodiment depicted in  FIG. 1 , the relay retrofit apparatus  10  is equipped with a weather protective shroud  20 . The shroud  20  is attached adjacent to the end of the plug  30  and is configured to protect the electrical pins  32  of the plug  30  from exposure to moisture, dirt, or any other substance that could adversely effect the electrical connection between the plug  30  and socket  70 . The socket  70  is shown in  FIG. 5  and will be described in greater detail below. In the embodiment depicted in  FIG. 1 , the shroud  20  includes a tab  25  designed to secure the shroud  20  to the electrical socket  70 , as shown in  FIG. 5 . The tab  25  prevents the plug  30  and socket  70  from detaching under normal operating conditions; thereby reducing the likelihood that the electrical current flowing from the socket  70  to the relay retrofit apparatus  10  will be lost. 
   Electrical Conductor 
   In the embodiment shown in  FIG. 1 , the plug  30  is coupled to a second relay  50  via wires  40  having first and second ends. In this embodiment, the relay retrofit apparatus includes four wires  40  that are encased within a protective insulative material  55 . The wires  40  can be made from any material that conducts electricity such as copper, zinc, tungsten, or iron. In addition, wires  40  of various length and thickness can be used to electrically couple the new relay  50  to the plug  30 . In alternate embodiments (not shown) the wiring could be braided copper wires, wound wiring, or electrical filaments. In short, anything with the capability to conduct electricity between the plug  30  and the new relay  50  can be used. 
   Relay 
   In the embodiment of the relay retrofit apparatus  10  shown in  FIG. 1 , the first ends of the wires  40  are connected to the plug  30  and the second ends are connected to a new relay  50 . In this particular embodiment, the new relay  50  is a 75 amp relay having a Double Pole Single Throw configuration. Alternate relays can be utilized in other embodiments of the present invention. As known in the art, a relay is an electrically-activated switch. A relay allows current to flow in one of two circuits, depending upon the switch&#39;s position or state. In general, relays allow electrical currents to flow between different sets of electrical contacts through the use of a “relay coil”. For example, particular relays are designed so that when the relay coil is not energized, a movable contact allows electricity to flow to one set of contacts. When the relay coil is energized from a power source, the contact will be moved to allow current to flow to a separate set of contacts. Relays come in a multitude of configurations. For example, there are Single Pole Single Throw (SPST) relays, Single Pole Double Throw (SPDT) relays, Double Pole Single Throw (DPST) relays, and Double Pole Double Throw (DPDT) relays. In a Single Pole Single Throw relay, a current will only flow through a set of contacts when the relay coil is energized. In the Single Pole Double Throw relay, current will flow between the movable contact and a first fixed contact when the relay coil is deenergized and between the movable contact and a second fixed contact when the relay coil is energized. In the Double Pole Single Throw relay, when the relay coil is energized, two separate and electrically isolated sets of contacts are moved to allow current to flow to two separate sets of contacts. In a Double Pole Double Throw configuration, the relay operates like the Single Pole Double Throw relay but with twice as many contacts, i.e., there are two completely isolated sets of contacts. 
   As illustrated by  FIG. 3 , the second ends of the wires  40  are connected directly to the new relay  50 . As stated above, the new relay used in this particular embodiment of the relay retrofit apparatus  10  is a 75 amp double pole single throw relay having an electrical contact configuration  60  that differs from the plug&#39;s  30  electrical contact configuration. Again referring to  FIG. 3 , in this particular embodiment, the electrical contact configuration  60  of the new relay  50  comprises two ring terminals, one vertical spade socket and one horizontal spade socket. As shown in  FIG. 3 , the ring terminals utilize screws to connect the wires  40  to the relay&#39;s  50  electrical contacts  60 . The remaining two wires plug into the relay  50  via spade pins. Again referring to  FIG. 3 , two wires configured with spade pin electrical contacts enter a connector  52  and plug into the relay  50 . One spade plugs into a substantially horizontal relay socket and the other spade plugs into a substantially vertical relay socket. Relays having different electrical contact configurations can be used in the present invention. 
   As shown in embodiments depicted in  FIGS. 1 and 3 , the new relay  50  includes attachment tabs  72 . The attachment tabs  72  comprise a hole and a plastic tab that extends outwardly from the new relay  50 . The attachment tabs  72  are configured to secure the new relay  50  to a structure using any means of attachment known in the art, such as a screw. For example, in  FIG. 5  the new relay  50  is shown secured to the vehicle&#39;s brake booster housing. 
   II. Use of a Relay in a Vehicle&#39;s Brake System 
   As described in greater detail below, the relay retrofit apparatus  10  described above can be used to replace or convert a first relay with a new relay without having to either: 1) install a new socket configured to receive the new relay, or 2) without having to splice and modify the socket to fit a new relay. The term socket  70  is also referred to as a “wiring harness” or a “wiring harness pigtail” by those skilled in the art. The terms “socket,” “vehicle socket,” “vehicle wiring harness,” and “vehicle wiring harness pigtail” can be used interchangeably and all refer generally to any electrical socket attached to wires. For example, the relay retrofit apparatus  10  can be used to replace relays used within a vehicle&#39;s braking system. It is important to note that replacing relays within a vehicle&#39;s braking system is an exemplary context for using the relay retrofit apparatus  10  and does not limit the use of the relay retrofit apparatus  10  in additional settings or environments. 
   Many vehicles utilize relays to provide electricity to an electric brake motor (not shown). In this context, the relay has contact points which are open when the relay coil is deenergized. On one side of the contacts is a power supply. The other side of the contacts goes to the load, which in this case is an electric brake motor. In order for the relay coil to energize and close the circuit to the brake motor, the coil must first be grounded. In this embodiment, a flow switch (not shown) is used to complete the ground. The flow switch monitors the hydraulic flow within the vehicle&#39;s brake system. If the flow switch detects pressure, the switch stays open, thereby keeping the ground open. If hydraulic pressure or flow is lost, either due to the engine being off or due to a broken belt leading to the vehicle&#39;s brake pump, the flow switch will close and complete the ground. Once grounded, the circuit is complete and the relay coil is energized. The energized relay coil in turn completes the circuit for the electric brake motor. 
   Therefore, when the ignition key is in the “on” position and the engine is running, the engine (i.e. the belts) provides hydraulic power to the vehicle&#39;s braking system. If the engine dies, or a belt brakes, the flow switch energizes the relay&#39;s coil which in turn completes a circuit and activates an electric brake motor. The brake motor provides enough power to the vehicle&#39;s brake system to allow the driver to safely bring the vehicle to a stop. Likewise, if the vehicle&#39;s ignition key is in the “off” position and the engine is not running, the flow switch will activate the relay when the brake pedal is depressed and power will be supplied to the vehicle&#39;s brake system. 
   III. Method of Using the Relay Retrofit Apparatus 
     FIG. 4  illustrates a prior art method of attaching a relay to a vehicle&#39;s electrical system. In this particular embodiment, the original relay  35  is connected to a vehicle&#39;s electrical system via a socket  70 . In the embodiment shown in  FIG. 4 , the original relay  35  is a 40 amp relay having a Single Pole Single Throw configuration. The original relay  35  is shown mounted to the vehicle&#39;s brake booster housing  80 . In this embodiment, the brake booster housing  80  serves only as a convenient structure on which to secure the original relay  35 . Other structures within a vehicle can be used to secure the original relay  35 . In fact, the original relay  35  does not have to be secured at all. 
   In the past, replacing the original relay  35  with a new relay having a different electrical contact configuration would require that the vehicle socket  70  (or “vehicle wiring harness”) be replaced. This would require splicing and modifying the vehicle&#39;s wiring harness to fit the new relay. To avoid this problem, the relay retrofit apparatus  10  allows the user to easily convert or replace the original relay  35  with a new relay  50  without having to splice a new vehicle socket into the vehicle&#39;s electrical system. 
   The method for replacing the original relay  35  with a new relay  50  comprises the following steps. First, the original relay  35  is disconnected and removed from the vehicle&#39;s electrical system. As shown in  FIG. 4 , the original relay  35  is mounted to the vehicle&#39;s brake booster housing  80 . Next, the user connects the wires  40  to a new relay  50  having a different contact configuration  60  than the original relay  35 . The new relay  50  shown in  FIG. 3  is a 75 amp double pole relay. After the new relay  50  is coupled to the plug  30 , the new relay  50  is secured in the same area as the original relay  35  and the plug  30  is connected to the vehicle socket  70 . After the relay retrofit apparatus  10  is installed and connected to the vehicle&#39;s electrical system, the user can test to ensure that the circuit is working correctly. In this embodiment, wherein the relay is used in the context of a vehicle&#39;s brake system, the brake motor should run when 1) the engine is off, 2) the ignition key is in the “off” position, and 3) the brake pedal is depressed. In addition, the brake motor should also run when 1) the engine is off, and 2) the ignition key is in the “on” position. When the engine is running, the brake motor should not run. If the above test are successful, the relay retrofit apparatus  10  has been properly installed into the vehicle&#39;s brake system. 
   Certain of the following claims are set forth in means plus function terminology. Here follows a description of the various means used to accomplish each claimed function. The coupling means include wiring, braided copper wires, wound wiring, electrical filaments, or a long piece of metal, for example. In short, anything with the capability to conduct electricity between the plug  30  and the new relay  50  can be used. The coupling means may be made from any material that conducts electricity such as copper, zinc, tungsten, or iron. In addition, coupling means of various length and thickness can be used. The connector means includes a socket, a wiring harness, or any device capable of connecting to the electrical contacts of a relay. For example, a connector means  52  is shown in  FIG. 3 .