SENSING DEVICES, SENSORS, AND METHODS FOR MONITORING ENVIRONMENTAL CONDITIONS

• US 20190172657A1
• Filed: 11/30/2018
• Published: 06/06/2019
• Est. Priority Date: 12/02/2017
• Status: Active Grant

• Current Assignee: Bellutech LLC
• Original Assignee: Bellutech LLC
• Inventors: Zhu, Weibin, Yazdi, Navid
• Granted Patent: US 11,011,323 B2
• Time in Patent Office: Days
• CPC Class Codes: B81B 2201/0278 Temperature sensors
• CPC Class Codes: B81B 2201/0292 Sensors not provided for in B81B2201/0207 - B81B2201/0285
• CPC Class Codes: B81B 2201/032 Bimorph and unimorph actuators, e.g. piezo and thermo
• CPC Class Codes: B81B 2203/0118 Cantilevers
• CPC Class Codes: B81B 3/0059 Constitution or structural means for controlling the movement not provided for in groups B81B3/0037 - B81B3/0056
• CPC Class Codes: G01K 3/04 in respect of time
• CPC Class Codes: G01K 5/486 using microstructures, e.g. made of silicon G01K7/015, G01K7/028, G01K7/226, G01K17/006 take precedence
• CPC Class Codes: G01K 5/56 constrained so that expansion or contraction causes a deformation of the solid
• CPC Class Codes: G01K 5/72 with electric transmission means for final indication
• CPC Class Codes: H01H 1/0036 Switches making use of microelectromechanical systems [MEMS] for electromagnetic relays H01H50/005; for electrostatic relays H01H59/0009
• CPC Class Codes: H01H 2001/0078 with parallel movement of the movable contact relative to the substrate
• CPC Class Codes: H01H 2239/06 Temperature sensitive

Abstract

Sensors, systems, and methods for monitoring environmental conditions, such as physical, electromagnetic, thermal, and/or chemical parameters within an environment, over extended periods of time with the use of one or more electromechanical sensing devices and electronic circuitry for processing an output of the sensing devices. The sensing devices each include a cantilevered structure and at least one contact configured for contact-mode operation with the cantilevered structure in response to the cantilevered structure deflecting toward or away from the contact when exposed to the parameter of interest. The cantilevered structure has at least first and second beams of dissimilar materials, at least one of which has at least one property that changes as a result of exposure to the parameter.

Claims

1. An electromechanical sensing device comprising a cantilevered structure and at least one contact configured for contact-mode operation with the cantilevered structure, the cantilevered structure being responsive to a parameter within an environment and to deflect toward or away from the contact thereof in response to the parameter in the environment, the cantilevered structure comprising first and second beams containing dissimilar first and second materials, respectively, the first and second beams being side-by-side, spaced apart so as to define a gap there between along the lengths of the first and second beams, and lying in a plane that contains the cantilevered structure, the first material having at least one property that changes due to exposure to the parameter and a change in the property causes the cantilevered structure to deflect in a direction lying in the plane of the first and second beams as a result of the dissimilarity of the first and second materials, the cantilevered structure being configured to contact and close or break contact and open the contact at a predetermined level of the parameter or from cumulative exposure to the parameter over time

2. The electromechanical sensing device according to claim 1, wherein the beams are parallel and the gap between the first and second beams is uniform along the lengths thereof.

3. The electromechanical sensing device according to claim 2, the cantilevered structure further comprising a connector that interconnects distal ends of the beams.

4. The electromechanical sensing device according to claim 3, wherein the connector is an extension of the second beam that extends transverse to a parallel direction of the beams.

5. The electromechanical sensing device according to claim 1, wherein the contact is a component of an elastic contact structure that enables the contact to deflect in response to a contact force imposed by the cantilevered structure.

6. The electromechanical sensing device according to claim 5, wherein the elastic contact structure comprises at least one support beam that suspends the contact from an anchor.

25. A method of sensing a parameter within an environment using the electromechanical sensing device of claim 1, the method comprising the steps of:

exposing the cantilevered structure to the parameter within the environment to cause the cantilevered structure to deflect in the direction lying in the plane of the first and second beams to contact and close the contact or break contact and open the contact; and

producing a digital output when the cantilevered structure contacts and closes or breaks contact and opens the contact thereof.

7. A sensor comprising:

an electromechanical sensing device comprising a cantilevered structure and at least one contact configured for contact-mode operation with the cantilevered structure, the cantilevered structure being responsive to a parameter within an environment and to deflect toward or away from the contact thereof in response to the parameter in the environment, the cantilevered structure comprising first and second beams containing dissimilar first and second materials, respectively, the first and second beams being side-by-side, spaced apart so as to define a gap there between along the lengths of the first and second beams, and lying in a plane that contains the cantilevered structure, the first material having at least one property that changes due to exposure to the parameter and a change in the property causes the cantilevered structure to deflect in a direction lying in the plane of the first and second beams as a result of the dissimilarity of the first and second materials, the cantilevered structure being configured to contact and close or break contact and open the contact at a predetermined level of the parameter or from cumulative exposure to the parameter over time; and

means for producing a digital output when the cantilevered structure contacts and closes at the contact thereof.

8. The sensor according to claim 7, wherein the parameter is at least one parameter chosen from the group consisting of temperature, moisture, electromagnetic radiation, a chemical, a biological agent, and nuclear particle radiation.

9. The sensor according to claim 7, wherein the property of the first material causes the first beam to expand and contract relative to the second beam in response to a change in temperature or humidity.

10. The sensor according to claim 7, wherein the first material is a curable organic material and the property of the first material changes as a result of the first material curing to form a polymeric material containing cross linked polymer chains.

11. The sensor according to claim 7, wherein the change in the property of the first material is reversible.

12. The sensor according to claim 7, wherein the change in the property of the first material is irreversible.

13. The sensor according to claim 7, wherein the second material is an electrical conductor that is electrically connected to the contact of the sensing device when the cantilevered structure contacts and closes the contact.

14. The sensor according to claim 7, wherein the second material is electrically non-conductive and the cantilevered structure further comprises an electrical conductor layer that is electrically connected to the contact of the sensing device when the cantilevered structure contacts and closes the contact.

15. The sensor according to claim 7, wherein the beams are parallel and the gap between the first and second beams is uniform along the lengths thereof.

16. The sensor according to claim 15, the cantilevered structure further comprising a connector that interconnects distal ends of the beams.

17. The sensor according to claim 16, wherein the connector is an extension of the second beam that extends transverse to a parallel direction of the beams.

18. The sensor according to claim 7, wherein the contact is a component of an elastic contact structure that enables the contact to deflect in response to a contact force imposed by the cantilevered structure.

19. The sensor according to claim 18, wherein the elastic contact structure comprises at least one support beam that suspends the contact from an anchor.

20. The sensor according to claim 7, wherein the sensing device is a first sensing device and the sensor comprises a plurality of additional sensing devices, each of the additional sensing devices comprises a cantilevered structure and at least one contact configured for contact-mode operation with the cantilevered structure thereof, the cantilevered structure of each of the additional sensing devices comprises first and second beams of the first and second materials, respectively, so that a change in the property of the first material causes the cantilevered structures of the additional sensing devices to deflect in a direction lying in a plane of the first and second beams as a result of the dissimilarity of the first and second materials, and each of the sensing devices produces a digital output when the cantilevered structure thereof contacts and closes or breaks contact and opens the contact thereof.

21. The sensor according to claim 20, wherein the electronic circuitry interfaces with the sensing devices to digitally process the digital outputs of the sensing devices and generate the sensor output therefrom over time as a cumulative output indicating the responses of the sensing devices to the parameter in the environment over time.

22. The sensor according to claim 20, wherein the property of the first material changes as a result of the first material absorbing or curing in response to the parameter in the environment, and the electronic circuitry interfaces with the sensing devices to receive the digital outputs of the sensing devices and relay the digital outputs as the sensor output over time as a cumulative output indicating the responses of the sensing devices to the parameter in the environment over time.

23. The sensor according to claim 20, wherein the electronic circuitry communicates with a subset of the sensing devices, the digital outputs of only the subset of sensing devices are processed by the electronic circuitry to generate the sensor output of the sensor, and a remainder of the sensing devices not part of the subset of sensing devices are responsive to levels of the parameter in the environment outside a range defined by the levels of the parameter in the environment to which the subset of sensing devices are responsive.

24. The sensor according to claim 7, wherein the cantilevered structures of the sensing devices are responsive to the changes in the parameter in the environment without any electrical power supplied to the cantilevered structures.