What is claimed is:
1. A transfer switch comprising:
output contacts;
primary input contacts;
secondary input contacts; and
a switch stack alternately connecting the output contacts to the primary input contacts and the secondary input contacts via at least one conductive path; and
a flux barrier at least partially positioned near the conductive path to minimize magnetic interaction with the conductive path as current travels through the switch stack.
2. The transfer switch of claim 1 wherein the flux barrier is a planar sheet.
3. The transfer switch of claim 3 wherein the planar sheet is made of steel.
4. The transfer switch of claim 1 wherein the transfer switch includes a plurality of conductive paths and the flux barrier isolates each of conductive paths from magnetic interaction with the other conductive paths.
5. The transfer switch of claim 4 wherein the switch stack includes multiple cassettes, each cassette including a conductive path.
6. The transfer switch of claim 5 wherein the flux barrier is secured to at least one of the cassettes.
7. The transfer switch of claim 5 wherein each cassette includes an output contact, a primary input contact and a secondary input contact.
8. The transfer switch of claim 5 wherein the flux barrier includes different portions that are at least partially positioned between each of the cassettes.
9. The transfer switch of claim 8 wherein the different portions of the flux barrier isolate each cassette entirely from magnetic interaction with the other cassettes.
10. The transfer switch of claim 8 wherein the different portions of the flux barrier are integral with one another.
11. A method of supplying current to an electric load comprising:
switching contacts within a transfer switch to alternately engage the switching contacts with primary input contacts that are coupled to a primary power source and secondary input contacts that are coupled to a secondary power source; and
minimizing magnetic interaction with a conductive path in the transfer switch as current travels through the transfer switch.
12. The method of claim 11 wherein minimizing magnetic interaction with the conductive path includes placing a flux barrier on both sides of the conductive path.
13. The method of claim 12 wherein the flux barriers are inserted along an entire length of the conductive path.
14. The method of claim 11 wherein the transfer switch includes a plurality of conductive paths and minimizing magnetic interaction between the conductive paths includes inserting a flux barrier between each of the conductive paths to isolate each conductive path from magnetic interaction with the other conductive paths.
15. The method of claim 14 wherein inserting a flux barrier between the conductive paths includes mounting at least one flux barrier to a cassette within the transfer switch.
16. The method of claim 14 wherein inserting a flux barrier between the conductive paths includes inserting the flux barrier into a switch stack.
17. A transfer switch comprising:
output contacts;
primary input contacts;
secondary input contacts;
a switch stack alternately connecting the output contacts to the primary input contacts and the secondary input contacts via a conductive path; and
means for reducing magnetic interaction with the conductive path in the transfer switch.
18. The transfer switch of claim 17, wherein the means for reducing magnetic interaction with the conductive path includes a flux barrier positioned near the conductive path to minimize magnetic interaction with the conductive path.
19. The transfer switch of claim 17, wherein the transfer switch includes a plurality of conductive paths, and the flux barrier includes a plurality of portions such that each portion is positioned between a unique pair of conductive paths.
20. The transfer switch of claim 17, wherein the means for reducing magnetic interaction between the conductive paths is a planar steel sheet.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A polymer roll transducer comprising:
an electroactive polymer roll having at least two layers of an electroactive polymer, wherein the electroactive polymer has an elastic modulus below 100 Mpa:
one or more electrodes disposed on the electroactive polymer roll; and
a securing means for securing the electroactive polymer roll to maintain a rolled configuration, wherein the securing means comprises an end cap.
2. The polymer roll transducer of claim 1, wherein the polymer roll transducer actuates linearly in response to an electric potential applied to the one or more electrodes.
3. The polymer roll transducer of claim 1, wherein the electroactive polymer roll is cut into a plurality of strands.
4. The polymer roll transducer of claim 3, wherein the strands are secured at three or more points to the securing means.
5. The polymer roll transducer of claim 1, wherein the electroactive polymer is capable of converting between mechanical and electrical energy.
6. A device for converting between electrical and mechanical energy, the device comprising:
a polymer roll transducer comprising a) an electroactive polymer including at least one active area and b) at least two electrodes in electrical communication with the active area wherein at least a portion of the electroactive polymer is wrapped upon itself to form a roll; and
at least one mechanical linkage coupled to the polymer roll transducer for securing the electroactive polymer roll to maintain a rolled configuration.
7. The device of claim 6, further comprising at least one support member coupled to the polymer roll transducer for providing at least one of i) a force that strains at least a portion of the polymer, ii) a force for controlling bending in the polymer roll transducer and iii) combinations thereof.
8. The device of claim 7, where the mechanical linkage is coupled to both the at least one support member and to the polymer roll member for allowing a force or a moment generated in a first portion of the polymer roll transducer to be communicated to a second portion of the polymer roll transducer such that the device provides precisely controlled angular movements, angular output andor angular stiffness control.
9. The device of claim 7, where the mechanical linkage comprises an end cap coupled to the support member in a manner allowing movement of the end cap in one or more directions.
10. The device of claim 9, wherein the end cap is rotationally coupled to the support member.
11. The device of claim 9, wherein an actuation of the active area of the electroactive polymer provides a force to moves the end cap in the one or more directions.
12. The device of claim 9, wherein a non-active area of the electroactive polymer provides a force to the move the end cap in the one or more directions.
13. The device of claim 9, further comprising a sensor for determining a position of the end cap.
14. The device of claim 7, further comprising a base rigidly coupled to the support member.
15. The device of claim 14, wherein the electroactive polymer is attached to the base.
16. The device of claim 14, wherein a plurality of mechanical linkages are rotationally coupled to a support member.
17. The device of claim 16, wherein the mechanical linkages and the support member are disposed within a hollow portion of the roll.
18. The device of claim 16, wherein the mechanical linkages are disk shaped.
19. The device of claim 16, wherein tensile forces, stored in a number of portions of the electroactive polymer, are transferred via the plurality of mechanical linkages to other portions of the electroactive polymer.
20. The device of claim 6, where at least one active area of the electroactive polymer comprises at least one sensor.
21. The device of claim 20, wherein the sensor is arranged for measuring or determining one or more of an angular position, an angular velocity or an angular position of more components of the device.
22. The device of claim 20, wherein the sensor is for measuring a strain of a component in the device.
23. The device of claim 6, wherein the roll is cut in one or more places for limiting a propagation of a force or a moment from a first portion of the roll to a second portion of the roll.
24. The device of claim 6, wherein the device includes a joint for coupling a first component of the device to a second component of the device and for allowing a relative rotation between the two components.
25. The device of claim 24, wherein the first component is a first support member and the second component is a second support member.
26. The device of claim 24, wherein the first component is the support member and the second component is the mechanical linkage.
27. The device of claim 6, wherein the mechanical linkage is a spring.
28. The device of claim 7, the support member comprises a first component rotationally coupled to a second component and the transducer is arranged in a manner to move the first component and the second component to different angular position relative to one another.
29. The device of claim 6, wherein the electroactive polymer is attached at one or more points to create moment arms of varying lengths about a rotational coupling point in the device wherein each moment arm is a distance between a force generated in the electroactive polymer and the rotational coupling point.
30. The device of claim 7, wherein at least a portion of the support member or the mechanical linkage is disposed in a hollow central part of the roll.
31. The device of claim 6, wherein the electroactive polymer is a dielectric elastomer.
32. The device of claim 6, wherein the electroactive polymer has an elastic modulus at most about 100 MPa.
33. The device of claim 6, wherein the support member comprises of plurality of telescoping tubes.
34. A device for converting between electrical and mechanical energy, the device comprising:
an electroactive polymer configured in a tube shape to form an electroactive polymer roll transducer, the electroactive polymer including at least one active area and at least two electrodes in electrical communication with the active area; and
at least one mechanical linkage coupled to the polymer roll transducer for securing the electroactive polymer roll.