Programmable Cable Adaptor for Connecting Different Automobile Computers to Diagnostic Equipment

1. Field of the Invention

The present invention relates generally to cable adaptors for interfacing and configuring signal-carrying conductors linking two pieces of electrical equipment, and more specifically to a programmable adaptor using pre-configured keys to selectively configure signal paths from one connector having a first pin configuration to another connector having a second pin configuration to allow communication between two pieces of electrical equipment, such as an on-board automobile computer and a piece of diagnostic equipment.

2. Brief Description of the Prior Art

The standard in modern automobiles is to have a computer or number of computers on-board the automobile to manage and control the various systems within the vehicle. For example, through the use of an oxygen sensor in the exhaust manifold, the computer can detect how efficient the fuel is being consumed by the engine and adjust the rate of fuel injection accordingly. In addition, the computer can monitor the electrical demand and regulate the output of the alternator, etc.

In the shop, each on-board computer can be connected to a piece of diagnostic equipment via cables and connectors, and the integrity of the system can be checked to ensure that it is functioning properly. In addition, the diagnostic equipment can receive signals indicating error codes generated by the computer indicating past or presently occurring events. The diagnostic equipment can also send signals to the computer to have the computer initiate certain activity to test the various systems of the automobile.

The need for the present invention stems from the fact that although on-board computers may use the same types of plugs, jacks or other connectors used to interface with the diagnostic equipment, the pin assignments for the signals may be different from one type of computer system to another automotive vehicle or for each computer on board the vehicle. For example, a connector typically used by on-board computers is the J1962, which has 16 contactor pins within the connector for communications, voltage measurements and control functions. Different on-board computer systems may use these 16 pins differently. For example, one vehicle computer system may use pin number 5 to transmit engine data, pin number 6 to transmit transmission data, and pin number 7 to provide an external control of the EGR solenoid valve, while another vehicle computer system may use pin number 5 to transmit air bag data, pin number 6 to transmit engine data and pin 7 to provide an oxygen sensor voltage measurement. Because of the variations in the configuration of pin assignments, it is sometimes difficult or confusing to use diagnostic equipment to properly recognize and process signals.

Before the present invention, a different adaptor was usually provided for each different combination of pin configurations. The major problem with having a separate adaptor for each different pin configuration is cost. It is expensive to manufacture a set of adaptors for every model year with new pin configurations to interface with new computer systems.

One alternative solution might be to connect input signal pins to output signal pins via wires and allegator clips. But such method would be tedious, impractical, and mistake-prone. Another alternative might be to provide a multiplexer within the diagnostic equipment to configure the signal paths. The problem here is that such method increases the complexity and cost of the diagnostic equipment, since every possible combination of signal routine must be accounted for.

Although no automotive related solutions to the problems mentioned above are known, approaches remotely related to the present invention have been provided in other fields. For example, in U.S. Pat. No. 5,130,893, Straate discloses a system for distributing input signal-carrying lines to selected output lines. More particularly, he provides a signal distribution system for distributing input telephone and cable TV lines to appropriate locations in a facility. This signal distribution system is a routing scheme where a multi-conductor cable, such as a telephone line, is selectively routed to multiple locations in a facility while another telephone line may be routed to other locations within or without the same facility. This system may be distinguished from the present invention because it does not reconfigure connections between the conductors of two different multiwire cables, but instead simply connects one or more input cables of a particular type to one or more output cables of the same type.

A need thus exists for an easy-to-use and low-cost apparatus to properly configure signal-conducting paths from one device to another device.

A programmable cable adaptor in accordance with the present invention includes a housing containing an internal circuit board having a plurality of conductive traces, an input connector with multiple pins or pin-receiving sockets, and an output connector with multiple pins or pin-receiving sockets. On the circuit board, there is a card edge receptacle with key-contacting pins electrically connected to the conductive traces which in turn electrically couple the receptacle pins to the input connector and/or the output connector. The key-contacting pins of the card edge receptacle are arrayed along at least one side of an elongated aperture for receiving an adaptor programming key generally referred to as a card edge key. The "key" is typically a small printed circuit board with conductive tabs on at least one side thereof with at least one tab being electrically connected to at least one other tab on the key by conductive traces. When the key is inserted into the receptacle aperture, electrical connections are made between the pins/sockets of the input connector and the pins/sockets of the output connector via the tabs and circuit traces on the key. Some of the pins/sockets of the input connector may be directly connected to the pins of the output connector without going through the card edge receptacle. These pins are usually industry standard pin assignments. In addition, some of the pins of the input connector may be connected to pins of the card edge receptacle and to the pins of the output receptacle as well. Typically, there are two such pins: one pin for voltage supply and one pin for ground.

Electrical components such as resistors, fuses, capacitors, transistors, diodes, neon lights, etc. may also be placed on the key or adaptor. For example, a resister or voltage divider can be used to drop a 10 volt signal from older computer systems to a 5 volt signal acceptable by the diagnostic equipment. It is anticipated that microprocessors might also be placed on the key and/or the adaptor circuit board as well. For example, a microprocessor may be used to multiplex incoming signals or to pre-process or pre-amplify the incoming signal for the diagnostic equipment. It is further anticipated that a small display, keypad, and/or switches could be made integral to the key and/or the adaptor housing to allow user input.

The cost of manufacturing a key is considerably lower than the cost of manufacturing an adaptor. Whenever there is a new configuration of pin assignments for new models of automobiles, only new keys need be made, not a whole adaptor. And such keys can be easily and quickly distributed to diagnostic equipment owners.

Although a programmable cable adaptor suitable for use in the automotive industry is disclosed, it is anticipated that the adaptor can be modified to meet similar requirements in other fields as well, such as the computer field for instance.

These and other objects and advantages of the present invention will no doubt become apparent to those skilled in the art after having read the following detailed description of the preferred embodiment which is illustrated in the several figures of the drawing.

FIG. 1 is a perspective view showing the input end connector of a programmable cable adaptor in accordance with the present invention;

FIG. 2 is a perspective view showing the output end connector of the programmable cable adaptor of FIG. 1 together with a key which can be used to configure the adaptor to meet certain connection requirements;

FIG. 3 is a schematic diagram showing the internal circuitry of a programmable cable adaptor in accordance with the present invention;

FIG. 4 shows a card edge printed circuit board also referred to herein as a key;

FIG. 5 shows an alternative embodiment of the key with a resistor on-board;

FIG. 6 shows another embodiment of the key with a microprocessor on-board; and

FIG. 7 illustrates still another embodiment of a connector assembly in accordance with the present invention.

In general, the present invention provides an adaptor module with an input connector to receive input signals from a device, in this case an on-board computer in an automobile, and properly configures the signal paths to an output connector for connection to another device, in this case a piece of diagnostic equipment. The configuration of at least some of the signal paths between connectors is achieved through the use of a card-edge-type connector which causes electrical interconnections to be made when a card-edge printed circuit board ("key") with edge tabs connected by trace routes is inserted into the connector.

In FIG. 1, a programmable cable adaptor is shown to include a housing 10, an input connector 12 on one end, an output connector 14 on the other end, and a slotted opening 16 on top of the housing. In this embodiment, the connector 12 accepts ODB-II connectors that follow J-1962 specifications.

FIG. 2 illustrates the opposite end of the adaptor showing the output connector 14, and the opening 16 with a "programming" key 18 exploded therefrom. In this example, the connector 14 is a DB15 type 15-pin connector.

Referring now to FIG. 3, which is intended to illustrate the internal interconnections between the several connectors, the card edge connector 16 is shown to have twelve pins 20 on one side, which are connected by traces 19, formed on a circuit board suggested by the dashed lines 17, to the pins 22 of the input connector 12. Similarly, twelve pins 24 on the opposite side of connector 16 are connected by circuit board traces 25 to the pin receptacles 26 of the output connector 14. The connectors 12 and 14 are also attached to the circuit board 17. Optionally, some of the pins of the input connector 12 may be connected by circuit board traces 27 directly to the pins of the output connector 14 or to both the pins of the output connector 14 and to pins on the other side of card edge connector 16. The card contacting surfaces 23 of the pins 22 and 24 of the edge connector may be simple conductive bumps, leaf spring contacts, spring-loaded pins or other suitable means. Furthermore, instead of using circuit board traces, discrete wires or ribbon cable conductors could be used to interconnect the general connectors.

Referring now to FIG. 4, a key 18 is depicted having at least one conductive tab 30 electrically linked to at least one other tab via holes 32 and/or trace routes 34. The preferred embodiment has tabs on both sides of the key. The key and its connecting conductors and contacts can take any suitable form.

FIG. 5 shows a different embodiment of the key 18 with a resistor 36 connected between two of the tabs. The resistor might serve to provide a voltage drop of the signal between the input connector and output connector. The resistor or pair of resistors might also serve as a means of identifying to the test equipment which specific key has been inserted into the receptacle 16. Other electrical components such as capacitors, inductors, filters, diodes, etc. could likewise be included in the key 18.

FIG. 6 shows still another embodiment of the key 18 having a microprocessor on-board. It is anticipated that a microprocessor 38 could be used to provide a variety of processing functions before the signal is passed between the devices. For example, a simple microprocessor could be used to multiplex the various input or output signals. It is further anticipated that a wired or wireless remote display and/or keypad along with the microprocessor may be included as part of the key and/or housing to allow user control of the signal or signaling function.

The input connector and the output connector of the present invention may be of any configuration having any number of pins/sockets. For example, in FIG. 3, the input connector has 16 flat pins and the output connector has 15 sockets, but any other suitable connector could be used. Not all of the pins/sockets need be used, and there may be more than one key for a particular computer system to test different systems on-board.

By inserting a key into the adaptor, the desired electrical connections are made between the pins/sockets of the input connector and the pins/sockets of the output connector via the tabs on the key. By inserting a key with a different set of conductive trace routes or connections between the tabs, the adaptor may be configured to connect different pins/sockets of the input connector to the pins/sockets of the output connector.

An alternative form of key and signal connection means is illustrated in FIG. 7 wherein instead of using metallic contacts and key tabs to selectively connect signal paths, coupling means in the form of a set of diode light sources (LEDs) 40 are shown disposed on one side of the key-receiving slot 46 and are connected to the pins/sockets 42 of the input connector 12. Coupling means in the form of a set of light sensors 44 are disposed on the opposite side of slot 46, perhaps in alignment with the sources 40, and the outputs thereof are connected to the pins/sockets 47 of the output connector 14. An opaque key 18c, having fiberoptics or other optical connectors 48 appropriately routed, will optically link at least some of the light sources 40 to some of the light detectors 44 and thus couple one signal path to another when inserted into the light paths and located in the position indicated by the dashed lines 49. This embodiment has the added feature that the input connector 12 will be electrically isolated from the output connector 14.

Although the present invention has been described above in terms of a specific embodiment, it is anticipated that alterations and modifications thereof will no doubt become apparent to those skilled in the art. It is therefore intended that the following claims be interpreted as covering all such alterations and modifications as fall within the true spirit and scope of the invention.