Controllable electronic switch
A controllable electronic switch for, e.g., controlling power distribution comprises a deformable member such as a bimetal arm that can be deformed to break an electrical path. The deformable member may be anchored at one end and in controllable contact with an electrical conductor at the other end. A heating element, such as a coil, can be used to selectively heat the deformable member. The controllable electronic switch can alternatively comprise a deformable member that is terminated in a wedge-shaped member. When the deformable member bends in response to being heated, the wedge-shaped member forces apart a pair of contacts thus breaking an electrical path. The wedge-shaped member and/or associated structures may be configured as a cam mechanism with multiple latching positions.
1. A method, comprising the steps of:
positioning in close proximity first and second elongate heat-deformable members, each of said first and second elongate heat-deformable members respectively having disposed thereon one of a pair of electrical contacts which rest in contact with each other when in a quiescent state;
electrically connecting a first one of said pair of electrical contacts to an incoming power line and the second one of said pair of electrical contacts to an output conductor;
placing a heating element proximate the second elongate heat-deformable member;
positioning a resting member between said first and second elongate heat-deformable members; and
controlling said heating element with a switch control signal, whereby said heating element controllably bends the second heat-deformable member while said resting member inhibits the first elongate heat-deformable member from following the bending of the second elongate heat-deformable member, thereby causing the pair of electrical contacts to open.
2. The method of claim 1 , wherein said output conductor comprises an output wire, further comprising the steps of
connecting the incoming power wire line to a base of the first elongate heat-deformable member; and
connecting said output wire proximate to the electrical contact disposed on the second elongate heat-deformable member, such that power from said incoming power line flows through said first elongate heat-deformable member, across the pair of electrical contacts, and through the output wire to a load but does not flow through said second elongate heat-deformable member.
3. The method of claim 2 , wherein said first elongate heat-deformable member acts as a safety arm which breaks circuit connection upon an over-current condition while the second heat-deformable member remains stationary due to the resting member, and wherein said second elongate heat-deformable member acts as a control arm breaking circuit connection in response to an electronic control signal while the first elongate heat-deformable member remains stationary due to the resting member.
4. The method of claim 1 , further comprising heating said heating element by providing electric current through a resistive tape disposed upon the second elongate heat-deformable member.
5. The method of claim 1 , further comprising heating said heating element by providing an electric current to a heating coil disposed proximate to the second elongate heat-deformable member.
6. The method of claim 1 , wherein said resting member is immobile.
7. The method of claim 1 , further comprising the step of moving said resting member in order to override the operation of either of the first or second elongate heat-deformable members, by controllably allowing the first and second elongate heat-deformable members to approach one another and the electrical contacts to thereby reconnect.
8. The method of claim 1 , wherein said resting member comprises a rotatable cam.
9. The method of claim 8 , further comprising the step of rotating said rotatable cam from a normal operating position to an override position, thereby causing the first and second elongate heat-deformable members to move towards one another and reconnect power to the load.
10. The method of claim 9 , wherein rotation of said rotatable cam is responsive to a manual switch.
11. The method of claim 8 , wherein said rotatable cam comprises a body having a length and a shorter width, such that in a first position the cam's body lengthwise separates the first and second elongate heat-deformable members, and, when one of said elongate heat-deformable members is in a bent position, rotation of the cam to a second position allows the unbent heat-deformable member to move towards the bent elongate heat-deformable member and re-connect the electrical contacts.
12. The method of claim 1 , wherein said first and second elongate heat-deformable members each comprises a bimetal arm.
13. The method of claim 12 , wherein each bimetal arm of said first and second elongate heat-deformable members has a top side comprised of a first metallic substance and a bottom side comprised of a second metallic substance having different thermal properties than the first metallic substance.
14. The method of claim 12 , wherein power is conveyed from an incoming power signal to a load when said pair of electrical contacts are in contact with one another, and wherein no power is conveyed to the load from said incoming power signal when said pair of electrical contacts are separated from one another.