Sealed control device with magnetically adjustable control parameter
A switch including a sealed housing; a magnetic sensor; and a control element configured to modify a control parameter for the switch in response to a signal from the sensor. In some aspects, the magnetic sensor is arranged to produce the signal in response to a magnetic field generated outside of the housing. In some aspects, the switch is a vibration switch, or is selected from the group consisting of a flow switch, a level switch, a temperature switch, a pressure switch, a proximity switch, and a velocity switch. In some aspects, the switch includes a two-wire configuration and first and second output pins arranged to provide an output signal for the switch and to receive a signal for programming the switch. In some aspects, the switch includes a two-wire configuration and a current-control element arranged to reduce current output for the switch.
1. A vibration switch, comprising:
a first electrical contact and a second electrical contact;
a sealed housing containing:
a switch element arranged in series between said first electrical contact and said second electrical contact, said switch element having a first state with a first impedance and a second state with a second impedance which is different from said first impedance;
a vibration sensor with a vibration sensor output;
a memory element for holding a threshold parameter;
a magnetic sensor; and,
a control element arranged to control the state of said switch element as a function of said vibration sensor output and said threshold parameter, wherein said threshold parameter is updated in response to a magnetic field selectively applied to said magnetic sensor.
2. The vibration switch of claim 1 wherein said control element is configured to receive a signal through said first electrical contract for updating said threshold parameter.
3. The vibration switch device of claim 2 , wherein said signal further comprises a latching mode parameter, a default open-closed parameter, and an operating delay parameter.
4. The vibration switch device of claim 1 , wherein said switch element first impedance is approximately an open circuit and said switch element second impedance is approximately zero.
5. The vibration switch device of claim 1 , wherein said vibration sensor is an accelerometer, a piezoelectric accelerometer, a pressure sensor or a velocity sensor.
6. The vibration switch device of claim 1 , wherein said control element further comprises conditioning electronics.
7. The vibration switch device of claim 6 , wherein said conditioning electronics comprises an amplifier, a filter, and an integrator.
8. The vibration switch device of claim 1 , further comprising a power interface configured to draw power from a source external to said sealed housing through said first electrical contact and said second electrical contact.
9. The vibration switch device of claim 8 , wherein said source is the power source for a load placed in series with said vibration switch device.
10. The vibration switch device of claim 1 , wherein an average of said vibration sensor output over a time duration is calculated and said threshold parameter is updated with a value about two times said average.
11. The vibration switch device of claim 1 , further comprising a light source, wherein said light source is cycled on and off in an observable pattern when said threshold parameter is updated.
12. A vibration switch device comprising:
a first electrical contact and a second electrical contact;
a sealed housing containing:
a switch element arranged in series between said first electrical contact and said second electrical contact, said switch element having a first state with a first impedance and a second state with a second impedance which is different from said first impedance;
a vibration sensor with a vibration sensor output;
a power interface configured to draw power from a source external to said sealed housing through said first electrical contact and said second electrical contact;
a memory element for holding a threshold parameter;
a control element arranged to control the state of said switch element as a function of said vibration sensor output and said threshold parameter; wherein said control element is configured to update said threshold parameter in response to a signal received through said first electrical contact.
13. The vibration switch device of claim 12 , wherein said signal further comprises a latching mode parameter, a default open-closed parameter, and an operating delay parameter.
14. A vibration switch comprising:
a first electrical contact and a second electrical contact;
a sealed housing containing:
a switch element arranged in series between said first electrical contact and said second electrical contact;
a vibration sensor with a vibration sensor output;
a memory element for holding a threshold parameter;
a control element having an under-threshold state wherein said control element causes said switch element to allow a first current to flow between said first electrical contact and said second electrical contact, an over-threshold state wherein said control element causes said switch element to have a low impedance, and a dropout state wherein said control element causes said switch element to allow a second current less than said first current to flow between said first electrical contact and said second electrical contact;
said control element configured to enter said over-threshold state when said vibration sensor output exceeds said threshold parameter;
said control element configured to change from said over-threshold state to said dropout state when said vibration sensor output is less than said threshold parameter; and
said control element configured to change from said drop-out state to said under-threshold state when said vibration sensor output is continuously less than said threshold parameter for a desired time duration.
15. The vibration switch of claim 14 , wherein said first electrical contact, said second electrical contact, and said control element are configured to receive a signal for updating said threshold parameter.
16. The vibration switch of claim 14 further comprising a magnetic sensor.
17. The vibration switch device of claim 14 , wherein said vibration sensor output is an average calculated over a second desired time duration.
18. The vibration switch device of claim 14 , wherein said first current is approximately 1 mA, said low impedance is approximately zero, and said second current is approximately zero.
19. The vibration switch device of claim 14 , wherein said vibration sensor is an accelerometer, a piezoelectric accelerometer, a pressure sensor, or a velocity sensor.
20. The vibration switch device of claim 14 , wherein said control element further comprises conditioning electronics.
21. The vibration switch device of claim 20 , wherein said conditioning electronics comprises an amplifier, a filter, and an integrator.
22. The vibration switch device of claim 14 , further comprising a power interface configured to draw power from a source to said sealed housing through said first electrical contact and said second electrical contact.
23. The vibration switch device of claim 22 , wherein said source is a power source for a load placed in series with said vibration switch device.
24. The vibration switch device of claim 14 , further comprising a magnetic sensor.
25. The vibration switch device of claim 24 , further comprising a magnet, wherein said control element is configured to update said threshold parameter in response to a magnetic field applied to said magnetic sensor.
26. The vibration switch device of claim 25 , wherein said threshold parameter is updated as a function of an average of said vibration sensor output over a third desired time duration, while said magnet is placed near said magnetic sensor.
27. The vibration switch device of claim 14 , further comprising a light source, wherein said light source is cycled on and off in an observable pattern when said threshold pattern is updated.
28. The vibration switch device of claim 14 , wherein said first electrical contact, said second electrical contact, and said control element are configured to receive a signal for updating said threshold parameter.
29. The vibration switch device of claim 28 , wherein said signal further comprises a latching mode parameter, a default open-closed parameter, and an operating delay parameter.