1. A timer comprising:
a rotatable ratchet gear having a plurality of teeth;
an electrically conducting pawl mechanism including a pawl, the pawl configured to engage one of the plurality of teeth on the ratchet gear; and
an electronic drive circuit electrically coupled to the pawl mechanism, the electronic drive circuit passing a current through the pawl mechanism such that the pawl advances the ratchet gear by one tooth pitch.
2. The timer of claim 1, wherein the pawl mechanism includes an alloy wire, the alloy wire contracting in length when the electronic drive circuit passes the current through the pawl mechanism.
3. The timer of claim 2, wherein the pawl mechanism includes a tension spring operably coupled to the pawl, the tension spring biasing the alloy wire back to a relaxed length when the electric drive circuit is not passing the current through the alloy wire.
4. The timer of claim 1, wherein the pawl mechanism includes an alloy wire extending between first and second pins and biased by a tension spring, the first and second pins electrically coupled to the electronic drive circuit.
5. The timer of claim 1, further comprising a pulley and wherein the pawl mechanism includes a nitinol wire, the nitinol wire bent around the pulley.
6. The timer of claim 1, further comprising a cam and a micro switch, the cam actuating the micro switch at least once per revolution of the ratchet gear.
7. The timer of claim 6, wherein timer further comprises a gear box, the gear box interposed between and operably coupled to the cam and the ratchet gear.
8. The timer of claim 1, wherein the electronic drive circuit includes a silicon controlled rectifier (SCR).
9. The timer of claim 1, wherein the electric drive circuit passes the current through the pawl mechanism at predetermined intervals.
10. The timer of claim 1, wherein the electronic drive circuit includes a silicon controlled rectifier (SCR), a capacitor, and a Zener diode in electrical communication with each other, the SCR conducting when the Zener diode reaches a Zener breakdown voltage, the conducting SCR permitting the capacitor to release an electric charge such that the current passes through the pawl mechanism.
11. The timer of claim 10, further comprising a cam and a micro switch, the cam actuating the micro switch at least once per revolution of the ratchet gear, and wherein the electronic drive circuit is configured to increase at rate at which the electronic drive circuit passes the current through the pawl mechanism when the cam actuates the micro switch.
12. The timer of claim 10, wherein the pawl mechanism includes an alloy wire, the alloy wire electrically coupled to a cathode of the silicon controlled rectifier (SCR).
13. The timer of claim 12, wherein the electronic drive circuit includes a capacitor, the capacitor in parallel with a combination of the Zener diode, the silicon controlled rectifier (SCR), and the alloy wire.
14. The timer of claim 13, wherein the electronic drive circuit further includes a first resistor in series with a diode, a resistance of the first resistor determining a time interval between charging and discharging of the capacitor, the diode rectifying an alternating current signal used to charge the capacitor.
15. The timer of claim 14, wherein the electronic drive circuit further includes a second resistor in series with the diode and in parallel with the first resistor, a combined resistance of the first resistor and second resistor determining a time interval between charging and discharging of the capacitor during at least a portion of operation of the electronic drive circuit.
16. An appliance timer comprising:
a base;
a rotatable ratchet gear operably coupled to the base, the ratchet gear having a plurality of teeth;
a metal pawl mechanism including a spring, a pawl, and a nickel titanium alloy wire operably coupled together and secured between first and second pins protruding from the base, the pawl configured to engage one of the plurality of teeth on the ratchet gear; and
an electronic drive circuit electrically coupled to the first and second pins, the electronic drive circuit passing a current through the pawl mechanism at regular intervals, the current causing the wire to contract such that the pawl advances the ratchet gear by one tooth pitch.
17. The appliance timer of claim 16, wherein the spring expands the wire after the current is removed from the pawl mechanism such that the pawl engages with a next one of the plurality of teeth on the ratchet gear.
18. The appliance timer of claim 16, wherein the spring returns the wire back to about an original length after the current is removed from the pawl mechanism such that the pawl engages with a next one of the plurality of teeth on the ratchet gear and the appliance timer further comprises a cam and a micro switch, the cam actuating the micro switch once per revolution of the ratchet gear.
19. A method of initiating a defrost cycle in an appliance comprising the steps of:
alternatively contracting and expanding an alloy wire to advance a ratchet gear;
initiating the defrost cycle when the ratchet gear has been advanced a predetermined amount.
20. The method of claim 19, wherein the contracting is performed by passing a current through the alloy wire at spaced apart intervals and the predetermined amount is one revolution.
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 method comprising:
a. adding an electrochemically active agent onto a support of a biosensor, wherein an electrode of the support is configured to cause a change in a redox state of the electrochemically active agent; and
b. adding an analyte that, in dependence upon the change of the redox state, interacts with a probe on the support.
2. The method of claim 1, wherein the change of the redox state allows the interaction between the analyte and the probe to occur.
3. The method of claim 1, wherein the change of the redox state increases a binding affinity between the analyte and the probe.
4. The method of claim 1, wherein the change of the redox state decreases a binding affinity between the analyte and the probe.
5. A method comprising:
a. providing a biosensor comprising a support in a solution,
i. the support comprising one or more electrodes, and a biomolecule interface layer having one or more immobilized probes thereon;
ii. the solution comprising an electrochemically active agent;
b. adding a biomolecule analyte to the solution;
c. reacting the electrochemically active agent using the one or more electrodes to produce an amount of H+ ions andor an amount of Off ions, wherein the pH of the solution close to the one or more electrodes is controlled by the amount of H+ ions andor the amount of Off ions produced;
d. collecting signals from the biosensor.
6. The method of claim 5, wherein the solution is an aqueous solution.
7. The method of claim 5, wherein the one or more immobilized probes comprises a pH sensitive probe.
8. The method of claim 7, wherein the pH sensitive probe is a fluorescent protein and optionally a green fluorescent protein.
9. (canceled)
10. The method of claim 7, wherein a first area of the biomolecule interface covers at least one area of the support not covered by the one or more electrode and a second area of the biomolecule interface covers at least one area of the one or more electrodes.
11. The method of claim 10, wherein the pH sensitive probe is immobilized on the first area and second area of the biomolecule interface.
12. The method of claim 11, further comprising determining the pH of the solution near the one or more electrode using a fluorescence intensity of an immobilized pH sensitive fluorescent protein immobilized on the second area of the biomolecule interface layer.
13. The method of claim 11, further comprising normalizing the fluorescence intensity of the immobilized pH sensitive fluorescent protein immobilized on the second area of the biomolecule interface layer with respect to the fluorescence intensity of the immobilized pH sensitive fluorescent protein immobilized on the first area of the biomolecule interface layer, and the pH is determined using the normalized fluorescence intensity.
14. The method of claim 5, wherein the one or more immobilized probes comprises an immobilized enzyme and the biomolecule analyte is an enzyme substrate.
15. The method of claim 5, wherein the one or more immobilized probes comprises an immobilized enzyme substrate and the biomolecule analyte is an enzyme.
16. The method of claim 5, further comprising measuring the pH using a sense electrode wherein the one or more electrodes comprises the sense electrode.
17. (canceled)
18. The method of claim 5, wherein the biosensor comprises a multisite array of test sites with each test site having the support in the solution and wherein one or more test condition for each test site can be independently varied.
19. (canceled)
20. The method of claim 18, wherein the pH of the solution close to the one or more electrodes in each test site is independently controlled.
21. The method of claim 18, wherein collecting signals from the biosensor include collecting varied signals from the multisite array of test sites to obtain a collection of varied signals.
22. A biosensor comprising a support in a solution,
a. the solution comprising an electrochemically active agent,
b. the support comprising one or more electrodes, and a biomolecule interface layer having one or more immobilized probes thereon, wherein the biosensor is configured to modify a pH of the solution near the one or more electrodes by electrochemically oxidizing or reducing the electrochemically active agent to produce H+ ions or OH\u2212 ions.
23. The biosensor of claim 22, wherein the solution is an aqueous solution.
24. The biosensor of claim 22, wherein the one or more immobilized probes comprises a pH sensitive probe.
25. The biosensor of claim 24, wherein the pH sensitive probe is a fluorescent protein and optionally a green fluorescent protein.
26. (canceled)
27. The biosensor of claim 24, wherein a first area of the biomolecule interface covers at least one area of the support not covered by the one or more electrode and a second area of the biomolecule interface covers at least one area of the one or more electrodes.
28. The biosensor of claim 27, wherein the pH sensitive probe is immobilized on the first area and second area of the biomolecule interface.
29. The biosensor of claim 28, wherein the biosensor is configured to determine the pH of the solution near the one or more electrode using a fluorescence intensity of an immobilized pH sensitive fluorescent protein immobilized on the second area of the biomolecule interface layer.
30. The biosensor of claim 28, wherein the biosensor is configured to normalize the fluorescence intensity of the immobilized pH sensitive fluorescent protein immobilized on the second area of the biomolecule interface layer with respect to the fluorescence intensity of the immobilized pH sensitive fluorescent protein immobilized on the first area of the biomolecule interface layer, and the biosensor is configured to determine the pH using the normalized fluorescence intensity.
31. The biosensor of claim 22, wherein the one or more immobilized probes comprises an immobilized enzyme and the biomolecule analyte is an enzyme substrate.
32. The biosensor of claim 22, wherein the one or more immobilized probes comprises an immobilized enzyme substrate and the biomolecule analyte is an enzyme.
33. The biosensor of claim 22, wherein the biosensor is configured to measure the pH using a sense electrode and wherein the one or more electrodes comprises the sense electrode.
34. (canceled)
35. The biosensor of claim 22, wherein the biosensor comprises a multisite array of test sites with each test site having the support in the solution and wherein one or more test condition for each test site can be independently varied.
36. (canceled)
37. The biosensor of claim 35, wherein the pH of the solution close to the one or more electrodes in each test site is independently controlled.
38. The biosensor of claim 35, wherein the biosensor is configured to obtain a collection of varied signals including varied signals from the multisite array of test sites.
39. A biosensor system comprising:
a. a support that includes an electrode;
b. a probe on the support;
c. an electrochemically active agent; and
d. an analyte that interacts with the probe on the support in dependence upon a change of a redox state of the electrochemically active agent, wherein the electrode is configured to control the change of the redox state of the electrochemically active agent.