Claims
- 1. An electrical connector matable to and separable from a separate mating electrical connector, the electrical connector including first and second contacts and a variable resistance member connecting the first and second contacts, the variable resistance member providing a shunt so that arcing does not occur when the first contact is disconnected from a mating terminal in the separate mating electrical connector, wherein the variable resistance member comprises a positive temperature coefficient resistance member.
- 2. The electrical connector of claim 1 wherein electrical resistance in the variable resistance member increases in response to increasing current to reduce the flow of current through the second contact before the second contact is disconnected from a mating terminal in the mating connector so that arcing does not occur when the second contact is disconnected.
- 3. The electrical connector of claim 2 wherein an increase in resistance in the variable resistance member lags an increase in current.
- 4. The electrical connector of claim 1 wherein the variable resistance member comprises a conductive polymer member with conductive particles immersed in a nonconductive polymer, increased I2R heating causing the nonconductive polymer to expand to disrupt conductive paths formed by interconnected conductive particles.
- 5. The electrical connector of claim 1 wherein the second contact is longer than the first contact so that the first contact is disconnected before the second contact as the electrical connector is unmated from the mating electrical connector.
- 6. The electrical connector of claim 1 including a latch that must be disengaged after the first contact is disconnected and before the second contact can be disconnected.
- 7. The electrical connector of claim 6 wherein disengagement of the latch provides sufficient time for the resistance of the variable resistance member to increase to a value such that the current in the second contact is below an arcing threshold before the latch can be disengaged.
- 8. The electrical connector of claim 7 wherein the connector includes first and second latches, disconnection of the first latch being required before disconnection of the first contact and disengagement of the second latch being required before disconnection of the second contact.
- 9. The electrical connector of claim 7 wherein movement of a lever on the connector moves the connector to disconnect the first contact.
- 10. The electrical connector of claim 9 wherein the latch can only be disengaged after movement of the lever to disconnect the first contact.
- 11. An electrical connector matable to and separable from a separate mating electrical connector, the electrical connector comprising;a main contact member; an auxiliary contact member; a variable resistive member connected between the main contact member and the auxiliary contact member, and disconnect means for discontinuously disconnecting first the main contact member and then the auxiliary contact member from terminal means in the mating electrical connector to reduce arcing when separation of the electrical connector from the mating electrical connector disconnects current through the electrical connector.
- 12. The electrical connector of claim 11 wherein current through the main contact member exceeds current through the auxiliary contact member prior to disconnection of the main contact member.
- 13. An electrical connector matable to and separable from a separate mating electrical connector, the electrical connector comprising:a main contact terminal including means for connecting the main contact terminal to an electrical conductor; an auxiliary contact terminal; and a resistive member connecting the auxiliary contact terminal to the main contact terminal, such that current passing through the auxiliary contact terminal also passes through the main contact terminal and the resistive member, the resistive member being characterized in that an increase in electrical resistance of the resistive member lags an inrush current through the resistive member, so that the resistive member carries a current approximately equal to the inrush current for a period of time referred to as a trip time, wherein the resistive member comprises a positive temperature coefficient resistive member; the electrical connector being configured to disconnect the main contact terminal from a mating electrical terminal in the separate mating electrical connector prior to disconnection of the auxiliary contact terminal from a mating electrical terminal in the mating electrical connector, the time to disconnect the main contact terminal by a distance sufficient such that an electrical arc cannot be sustained comprising a disconnect time, the disconnect time being less than the trip time so that arcing is prevented upon disconnection of the main contact terminal.
- 14. The electrical connector of claim 13 wherein the main contact terminal carries a larger current when connected to the mating electrical connector than the auxiliary contact terminal carries when both the main and the auxiliary contact terminals are connected to the mating electrical connector.
- 15. The electrical connector of claim 13 wherein the auxiliary terminal is disconnected from a mating electrical terminal after a finite time interval from the disconnecting of the main contact terminal, the finite time interval being long enough for resistance in the resistive member to increase sufficiently to reduce the current through the auxiliary terminal below an arcing threshold, so that arcing does not occur upon disconnection of the auxiliary contact terminal.
- 16. The electrical connector of claim 13 wherein the electrical resistance of the resistive member is greater than the electrical resistance of the main contact terminal so long as the main contact terminal remains connected to the mating electrical terminal.
- 17. An electrical connector matable to and separable from a separate mating electrical connector, the electrical connector comprising:a main contact terminal; an auxiliary contact terminal; a switch comprising a positive temperature coefficient resistance member connected between the main contact terminal and the auxiliary contact terminal, the switch being characterized by a finite trip time to switch from a first relatively low resistance state to a second relatively higher resistance state; the electrical connector being configured so that the main contact terminal is separable from a mating terminal in the separate mating electrical connector in a disconnect time that is less than the trip time to reduce arcing when the main contact terminal is disconnected when current flows through the electrical connector and the separate mating electrical connector, disconnection of the auxiliary contact being delayed relative to disconnection of the main contact by a sufficient time so that both the main contact and the auxiliary contact can be disconnected without arcing.
- 18. The electrical connector of claim 17 wherein the main contact terminal has a resistance that is less than the relatively low resistance state of the switch.
- 19. The electrical connector of claim 17 wherein the switch exhibits a nonlinear increase in resistance relative to current over a specified temperature range.
- 20. An electrical connector that can be disconnected, without damage due to arcing, from a separable mating electrical connector while carrying electrical energy above an arcing threshold, the electrical connector comprising:a main contact matable with and unmatable from a mating contact in the mating electrical connector; at least one auxiliary contact; a positive temperature coefficient resistor between the main contact and the auxiliary contact; the main contact being separable from the mating contact before the auxiliary contact is disconnected from a circuit including the mating contact in the mating connector so that the resistance in the positive temperature coefficient resistor increases after disconnection of the main contact from the mating contact and prior to disconnection of the auxiliary contact from the circuit so that both the main contact and the auxiliary contact can be disconnected without arcing.
- 21. The electrical connector of claim 20 wherein the auxiliary contact is matable with and unmatable from the same mating contact to which the main contact is matable.
- 22. The electrical connector of claim 20 wherein the main contact is shorter than the auxiliary contact.
- 23. The electrical connector of claim 20 wherein the positive temperature coefficient resistor comprises a separate component having leads connected to both the main and the auxiliary contact.
- 24. The electrical connector of claim 20 wherein the positive temperature coefficient resistor is bonded between the main contact and the auxiliary contact.
- 25. The electrical connector of claim 24 wherein the positive temperature coefficient resistor comprises a molded member secured on one side to a central section of the main contact and secured on an opposite side to the auxiliary contact.
- 26. The electrical connector of claim 20 wherein the main contact and the auxiliary contact each comprise blades.
- 27. The electrical connector of claim 20 wherein the positive temperature coefficient resistor comprises a conductive polymer.
- 28. The electrical connector of claim 27 wherein the conductive polymer comprises a polymer with a conductive particulate filler dispersed in the polymer.
- 29. The electrical connector of claim 20 wherein the main contact comprises a lower resistance electrical path than an electrical path through the auxiliary contact and the positive temperature coefficient resistor so that a rapid increase in current occurs through the positive temperature coefficient resistor and the auxiliary contact after the main contact is separated from the mating contact.
- 30. The electrical connector of claim 29 wherein the resistance of the positive temperature coefficient resistor increases sufficiently rapidly between separation of the main contact and disconnection of the auxiliary contact so that the electrical energy flowing through the auxiliary contact is reduced below the arcing threshold after separation of the main contact and before disconnection of the auxiliary contact.
- 31. The electrical connector of claim 20 wherein the positive temperature coefficient resistor resets to a low resistance state after the electrical connector is unmated from the mating electrical connector.
- 32. The electrical connector of claim 20 wherein the current carrying capacity of the main contact is greater than the current carrying capacity of the auxiliary contact.
- 33. The electrical connector of claim 20 wherein the electrical connector includes a housing matable with a mating housing in the mating electrical connector, the two housings limiting the minimum time between separation of the main contact from the mating contact and disconnection of the auxiliary contact to a time sufficient for the electrical energy flowing through the auxiliary contact to fall below the arcing threshold.
- 34. The electrical connector of claim 33 wherein the housing comprises means for assuring that unmating of the connectors, while the contacts are in a position susceptible to arcing is unidirectional.
- 35. An electrical connector matable to and unmatable from a separate mating connector, the electrical connector comprising:a main contact; an auxiliary contact; a variable resistance positive temperature coefficient member between the main contact and the auxiliary contact; a first latch disengagable from the mating connector, to disconnect the main contact from mating terminal means in the mating connector; a second latch disengagable from the mating connector after the main contact has been disconnected from the mating terminal means, the auxiliary contact being disconnectable from a mating terminal means in the mating electrical connector upon disengagement of the second latch.
- 36. The electrical connector of claim 35 wherein the variable resistance positive coefficient member comprises means for first shunting current to the auxiliary contact after the main contact has been disconnected and means for increasing the resistance to current through the auxiliary contact before the auxiliary contact is disconnected.
- 37. The electrical connector of claim 35 wherein the electrical connector can be unmated from the mating connector only by first disengaging the first latch and subsequently disengaging the second latch.
- 38. An electrical connector disconnectable from a separate mating electrical connector without arcing, the electrical connector comprising:main contact means and auxiliary contact means, each matable with and unmatable from mating terminal means in the mating electrical connector as the electrical connector is separated from the mating electrical connector; resistive means comprising positive temperature coefficient resistive means between the main contact means and the auxiliary contact means, the main contact means comprising a lower resistance path than a path through the resistive means and the auxiliary contact means; the electrical connector being configured so that, when the electrical connector is unmated and separated from the mating electrical connector, the main contact means is disconnected from the mating terminal means in the mating electrical connector before disconnection of the auxiliary contact means and the mating terminal means so that a current path through the auxiliary contact means and the resistive means to the mating terminal means remains intact after disconnection of the main contact means from the mating terminal means; the resistance through the resistive means and the auxiliary contact means being greater when the auxiliary contact means is disconnected from the mating terminal means than when the main contact means is disconnected from the mating terminal means so that arcing does not occur when the main contact means and the auxiliary contact means are sequentially disconnected from the mating terminal means.
- 39. The electrical connector of claim 38 wherein the resistive means comprises a variable resistance member.
- 40. An arc avoidance electrical connector disconnectable and separable from a mating electrical connector under load, the electrical connector including:a main contact disconnectable from a mating terminal in the mating electrical connector as the mating electrical connector is unmated and separated from the electrical connector; shunting means for shunting sufficient current through an alternate path to the mating electrical connector as the main contact is disconnected from the mating terminal so that arcing does not occur as the main contact is disconnected from the mating terminal, wherein the shunting means includes a positive temperature coefficient resistive member.
- 41. An electrical connector matable to and separable from a separate mating electrical connector, the electrical connector comprising;a main contact member; an auxiliary contact member; a variable resistive member connected between the main contact member and the auxiliary contact member, wherein the variable resistive member comprises a positive temperature coefficient resistive member and disconnect means for disconnecting first the main contact member and then the auxiliary contact member in two stages to reduce arcing when disconnection of the electrical connector disconnects current through the electrical connector.
CROSS REFERENCE TO PRIOR CO-PENDING PATENT APPLICATIONS
This application claims the benefit of Provisional Patent Application Serial No. 60/309,424 filed Aug. 1, 2001 and of Provisional Patent Application Serial No. 60/324,111 filed Sep. 21, 2001.
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EP |
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Provisional Applications (2)
|
Number |
Date |
Country |
|
60/309424 |
Aug 2001 |
US |
|
60/324111 |
Sep 2001 |
US |