Claims
- 1. An electrical relay comprising:
a relay housing containing a switching cavity; first and second fixed contact pads, each attached to the relay housing in the switching cavity and having a wettable surface; first and second switching contacts positioned between the first and second fixed contact pads, each of the first and second switching contacts having a wettable surface; a moveable contact carrier supporting the first and second switching contacts; a first conducting liquid volume in wetted contact with the first switching contact and the first fixed contact pad; a second conducting liquid volume in wetted contact with the second switching contact and the second fixed contact pad; and an actuator in a rest position, coupling the contact carrier to the relay housing and operable to move the contact carrier in a first direction, to decrease the distance between the first switching contact and the first fixed contact pad and increase the distance between the second switching contact and the second fixed contact pad, and a second direction to increase the distance between the first switching contact and the first fixed contact pad and decrease the distance between the second switching contact and the second fixed contact pad, wherein:
motion of the contact carrier in the first direction causes the first conducting liquid volume to form a connection between the first switching contact and the first fixed contact pad and causes the second conducting liquid volume to separate into two droplets, thereby breaking a connection between the second switching contact and the second fixed contact pad; and motion of the contact carrier in the second direction causes the first conducting liquid volume to separate into two droplets, thereby breaking the connection between the first switching contact and the first fixed contact pad and causes the second conducting liquid volume to form a connection between the second switching contact and the second fixed contact pad.
- 2. An electrical relay in accordance with claim 1, wherein the actuator is a piezoelectric actuator.
- 3. An electrical relay in accordance with claim 1, wherein the actuator is a magnetorestrictive actuator.
- 4. An electrical relay in accordance with claim 1, wherein the first and second conducting liquid volumes are liquid metal droplets.
- 5. An electrical relay in accordance with claim 1, wherein the first and second conducting liquid volumes are such that connected volumes remain connected when the actuator is returned to its rest position, and separated droplets remain separated when the actuator is returned to its rest position.
- 6. An electrical relay in accordance with claim 1, further comprising electrical connections to the first and second fixed contact pads and the first and second switching contacts.
- 7. An electrical relay in accordance with claim 6, wherein the electrical connections to the first and second fixed contact pads and the electrical connections to the first and second switching contacts are electrically shielded by ground conductors.
- 8. An electrical relay in accordance with claim 6, wherein the electrical connection to the first and second switching contacts comprises:
a first moveable contact supported by the contact carrier and electrically coupled to the first and second switching contacts; a third fixed contact pad positioned in proximity to the first moveable contact and having a surface wettable by conducting liquid; and a third conducting liquid volume in wetted contact with and forming an electrical connection between the first moveable contact and the third fixed contact pad, wherein the third conducting liquid volume is sized so that the electrical connection between the first moveable contact and the third fixed contact pad is maintained when the contact carrier is moved.
- 9. An electrical relay in accordance with claim 1, wherein the relay housing comprises:
a circuit substrate supporting electrical connections to the actuator, the first and second switching contacts and the first and second fixed contact pads; a cap layer; and a switching layer positioned between the circuit substrate and the cap layer and having the switching cavity formed therein.
- 10. An electrical relay in accordance with claim 9, wherein at least one of the electrical connections to the first and second fixed contact pads and the first and second switching contacts passes through the circuit substrate and terminates in a solder ball.
- 11. An electrical relay in accordance with claim 9, wherein at least one the electrical connections to the first and second fixed contact pads and the first and second switching contacts terminates at an edge of the switching layer.
- 12. An electrical relay in accordance with claim 9, wherein at least one of the electrical connections to the first and second fixed contact pads and the first and second switching contacts is a trace deposited on the upper surface of the circuit substrate.
- 13. An electrical relay in accordance with claim 12, further comprising a first plurality of ground traces deposited on the upper surface of the circuit substrate either side of the at least one electrical connection.
- 14. An electrical relay in accordance with claim 13, further comprising a second plurality of ground traces deposited on the lower surface of the circuit substrate, the first plurality of ground traces being electrically connected to the second plurality of ground traces by one or more vias passing through the circuit substrate.
- 15. An electrical relay in accordance with claim 9, manufactured by a method of micro-machining.
- 16. A method for switching between a first electrical circuit, between a first switching contact and a first fixed contact pad, and a second electrical circuit, between a second switching contact and a second fixed contact pad, in a relay, the first and second switching contacts being supported on a contact carrier and positioned between the first and second fixed contact pads, the method comprising:
if the first electrical circuit is to be selected:
energizing an actuator to move the contact carrier in a first direction, thereby moving the first switching contact towards the first fixed to contact pad so that a first conducting liquid volume, supported by at least one of the first switching contact and the first fixed contact pad, wets between the first switching contact and the first fixed contact pad and completes the first electrical circuit; and if the second electrical circuit is to be selected:
energizing the actuator to move the contact carrier in a second direction, thereby moving the second switching contact towards the second fixed contact pad so that a second conducting liquid volume, supported by at least one of the second switching contact and the second fixed contact pad, wets between the second switching contact and the second fixed contact pad and completes the second electrical circuit.
- 17. A method in accordance with claim 16, wherein:
motion of the contact carrier in the first direction moves the second switching contact away from the second fixed contact pad, so that the second conducting liquid volume cannot wet between the second switching contact and the second fixed contact pad, thereby breaking the second electrical circuit; and motion of the contact carrier in the second direction moves the first switching contact away from the first fixed contact pad, so that the first conducting liquid volume cannot wet between the first switching contact and the first fixed contact pad, thereby breaking the first electrical circuit.
- 18. A method in accordance with claim 16, further comprising:
if the first electrical circuit is to be selected:
de-energizing the actuator after the first conducting liquid wets between the first switching contact and the first fixed contact pad; and if the second electrical circuit is to be selected:
de-energizing the actuator after the second conducting liquid wets between the second switching contact and the second fixed contact pad.
- 19. A method in accordance with claim 16, wherein the first actuator is a piezoelectric actuator and wherein energizing the first actuator comprises applying an electrical voltage across the piezoelectric actuator.
- 20. A method in accordance with claim 16, wherein the first actuator is a magnetorestrictive actuator and wherein energizing the first actuator comprises applying a magnetic field across the magnetorestrictive actuator.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to the following co-pending U.S. patent applications, being identified by the below enumerated identifiers and arranged in alphanumerical order, which have the same ownership as the present application and to that extent are related to the present application and which are hereby incorporated by reference:
[0002] Application 10010448-1, titled “Piezoelectrically Actuated Liquid Metal Switch”, filed May 2, 2002 and identified by Ser. No. 10/137,691;
[0003] Application 10010529-1, “Bending Mode Latching Relay”, and having the same filing date as the present application;
[0004] Application 10010531-1, “High Frequency Bending Mode Latching Relay”, and having the same filing date as the present application;
[0005] Application 10010570-1, titled “Piezoelectrically Actuated Liquid Metal Switch”, filed May 2, 2002 and identified by Ser. No. 10/142,076;
[0006] Application 10010571-1, “High-frequency, Liquid Metal, Latching Relay with Face Contact”, and having the same filing date as the present application;
[0007] Application 10010572-1, “Liquid Metal, Latching Relay with Face Contact”, and having the same filing date as the present application;
[0008] Application 10010573-1, “Insertion Type Liquid Metal Latching Relay”, and having the same filing date as the present application;
[0009] Application 10010617-1, “High-frequency, Liquid Metal, Latching Relay Array”, and having the same filing date as the present application;
[0010] Application 10010618-1, “Insertion Type Liquid Metal Latching Relay Array”, and having the same filing date as the present application;
[0011] Application 10010634-1, “Liquid Metal Optical Relay”, and having the same filing date as the present application;
[0012] Application 10010640-1, titled “A Longitudinal Piezoelectric Optical Latching Relay”, filed Oct. 31, 2001 and identified by Ser. No. 09/999,590;
[0013] Application 10010643-1, “Shear Mode Liquid Metal Switch”, and having the same filing date as the present application;
[0014] Application 10010644-1, “Bending Mode Liquid Metal Switch”, and having the same filing date as the present application;
[0015] Application 10010656-1, titled “A Longitudinal Mode Optical Latching Relay”, and having the same filing date as the present application;
[0016] Application 10010663-1, “Method and Structure for a Pusher-Mode Piezoelectrically Actuated Liquid Metal Switch”, and having the same filing date as the present application;
[0017] Application 10010664-1, “Method and Structure for a Pusher-Mode Piezoelectrically Actuated Liquid Metal Optical Switch”, and having the same filing date as the present application;
[0018] Application 10010790-1, titled “Switch and Production Thereof”, filed Dec. 12, 2002 and identified by Ser. No. 10/317,597;
[0019] Application 10011055-1, “High Frequency Latching Relay with Bending Switch Bar”, and having the same filing date as the present application;
[0020] Application 10011056-1, “Latching Relay with Switch Bar”, and having the same filing date as the present application;
[0021] Application 10011065-1, “Push-mode Latching Relay”, and having the same filing date as the present application;
[0022] Application 10011121-1, “Closed Loop Piezoelectric Pump”, and having the same filing date as the present application;
[0023] Application 10011329-1, titled “Solid Slug Longitudinal Piezoelectric Latching Relay”, filed May 2, 2002 and identified by Ser. No. 10/137,692;
[0024] Application 10011344-1, “Method and Structure for a Slug Pusher-Mode Piezoelectrically Actuated Liquid Metal Switch”, and having the same filing date as the present application;
[0025] Application 10011345-1, “Method and Structure for a Slug Assisted Longitudinal Piezoelectrically Actuated Liquid Metal Optical Switch”, and having the same filing date as the present application;
[0026] Application 10011397-1, “Method and Structure for a Slug Assisted Pusher-Mode Piezoelectrically Actuated Liquid Metal Optical Switch”, and having the same filing date as the present application;
[0027] Application 10011398-1, “Polymeric Liquid Metal Switch”, and having the same filing date as the present application;
[0028] Application 10011410-1, “Polymeric Liquid Metal Optical Switch”, and having the same filing date as the present application;
[0029] Application 10011436-1, “Longitudinal Electromagnetic Latching Optical Relay”, and having the same filing date as the present application;
[0030] Application 10011437-1, “Longitudinal Electromagnetic Latching Relay”, and having the same filing date as the present application;
[0031] Application 10011458-1, “Damped Longitudinal Mode Optical Latching Relay”, and having the same filing date as the present application;
[0032] Application 10011459-1, “Damped Longitudinal Mode Latching Relay”, and having the same filing date as the present application;
[0033] Application 10020013-1, titled “Switch and Method for Producing the Same”, filed Dec. 12, 2002 and identified by Ser. No. 10/317,963;
[0034] Application 10020027-1, titled “Piezoelectric Optical Relay”, filed Mar. 28, 2002 and identified by Ser. No. 10/109,309;
[0035] Application 10020071-1, titled “Electrically Isolated Liquid Metal Micro-Switches for Integrally Shielded Microcircuits”, filed Oct. 8, 2002 and identified by Ser. No. 10/266,872;
[0036] Application 10020073-1, titled “Piezoelectric Optical Demultiplexing Switch”, filed Apr. 10, 2002 and identified by Ser. No. 10/119,503;
[0037] Application 10020162-1, titled “Volume Adjustment Apparatus and Method for Use”, filed Dec. 12, 2002 and identified by Ser. No. 10/317,293;
[0038] Application 10020241-1, “Method and Apparatus for Maintaining a Liquid Metal Switch in a Ready-to-Switch Condition”, and having the same filing date as the present application;
[0039] Application 10020242-1, titled “A Longitudinal Mode Solid Slug Optical Latching Relay”, and having the same filing date as the present application;
[0040] Application 10020473-1, titled “Reflecting Wedge Optical Wavelength Multiplexer/Demultiplexer”, and having the same filing date as the present application;
[0041] Application 10020540-1, “Method and Structure for a Solid Slug Caterpillar Piezoelectric Relay”, and having the same filing date as the present application;
[0042] Application 10020541-1, titled “Method and Structure for a Solid Slug Caterpillar Piezoelectric Optical Relay”, and having the same filing date as the present application;
[0043] Application 10030438-1, “Inserting-finger Liquid Metal Relay”, and having the same filing date as the present application;
[0044] Application 10030440-1, “Wetting Finger Liquid Metal Latching Relay”, and having the same filing date as the present application;
[0045] Application 10030521-1, “Pressure Actuated Optical Latching Relay”, and having the same filing date as the present application;
[0046] Application 10030522-1, “Pressure Actuated Solid Slug Optical Latching Relay”, and having the same filing date as the present application; and
[0047] Application 10030546-1, “Method and Structure for a Slug Caterpillar Piezoelectric Reflective Optical Relay”, and having the same filing date as the present application.