Motion sensing device

• US 4,797,661 A
• Filed: 08/31/1987
• Issued: 01/10/1989
• Est. Priority Date: 08/31/1987
• Status: Expired due to Fees

• Current Assignee: Robert Hooke Memorial Laboratories Incorporated
• Original Assignee: Robert Hooke Memorial Laboratories Incorporated
• Inventors: Wiley, Wallace F.
• Primary Examiner(s): Swann, III, Glen R.
• Assistant Examiner(s): Mullen, Jr., Thomas J.
• Application Number:
  US07/091,447
• Time in Patent Office: 498 Days
• Field of Search: 340/689, 340/669, 340/65, 340/63, 340/664, 340/566, 73/516 LM, 73/505, 73/654, 33/366, 200/61.47, 200/52 A, 324/93-94, 307/131
• US Class Current: 340/664
• CPC Class Codes: G08B 13/02 Mechanical actuation
• CPC Class Codes: G08B 13/1436 with motion detection

Abstract

This invention relates to a device adapted to sensing motion when powered by passage of an electric current between two electrodes that is comprised of a container partially filled with an electrically conductive liquid along with two electrodes in contact with the conductive liquid at least one of which is only partially in contact with said conductive liquid. Motion of the liquid causes a change in resistance between the electrodes which may be detected as a change in current flow. These changes in current flow can be amplified and used to activate an alarm or other signal device.

Claims

1. A device adapted to sensing motion when activated by passage of an electric current between two electrodes comprised of a container partially filled with a mobile, conductive liquid and first and second electrodes in contact with said conductive liquid with at least said second electrode being partially immersed in said conductive liquid, the immersed portion of said second electrode receiving the electric current from above the surface of the liquid through a resistor.

2. The device of claim 1 wherein the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

3. The device of claim 1 wherein the container is a sealed container and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

4. The device of claim 1 wherein the container is a sealed container, both electrodes are made of the same material and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

5. The device of claim 1 wherein the container is cylindrical, the container is sealed, both electrodes are made of the same material and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

6. The device of claim 1 wherein the container is cylindrical, the container is sealed, both electrodes are made of the same material, one electrode is centrally located within the container and partially immersed in the conductive liquid and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

7. The device of claim 1 wherein the container provides one electrode and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

8. The device of claim 1 wherein the container provides one electrode, the container is cylindrical and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

9. The device of claim 1 wherein the container provides one electrode, the container is cylindrical, the container is sealed and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

10. The device of claim 1 wherein the container provides one electrode, the container is cylindrical, the container is sealed, both electrodes are made of the same material and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

11. The device of claim 1 wherein the container provides one electrode, the container is cylindrical, the container is sealed, both electrodes are made of the same material, one electrode is centrally located within the container and partially immersed in said conductive liquid and the resistance between said electrodes is from about 0.1 ohm to about 10⁷ ohms.

12. A device adapted to sensing motion when activated by passage of an electric current between two electrodes comprised of a cylindrical, sealed container partially filled with a mobile, conductive liquid, said container providing one of two electrodes, the second electrode being a centrally positioned cylindrical wire partially immersed in said conductive liquid, the immersed portion of said second electrode receiving the electric current from above the surface of the liquid through a resistor both electrodes being made of the same material, with the resistance between said electrodes being in the range of from about 10³ ohms to about 10⁶ ohms.

13. The device of claim 12 wherein the conductive liquid has a specific resistance of from about 10⁴ to 10⁹ ohms-cm and a viscosity not greater than about 20 centipoise and the wire has a diameter not greater than about one-eighth of an inch.

14. The device of claim 12 wherein the conductive liquid has a specific resistance of from about 10⁴ to 10⁹ ohms-cm and a viscosity not greater than about 2 centipoise and the wire has a diameter not greater than about one-eighth of an inch.

15. The device of claim 12 wherein the conductive liquid has a specific resistance of from about 10⁴ to 10⁹ ohms-cm and a viscosity not greater than about 20 centipoise, the wire has a diameter not greater than about one-eighth of an inch and the resistance between the electrodes is from about 5×

10⁴ ohms to about 5×

10⁵ ohms.

16. The device of claim 12 wherein the conductive liquid has a specific resistance of from about 10⁶ to 10⁸ ohm-cm and a viscosity not greater than about 20 centipoise and the wire has a diameter not greater than about one-eighth of an inch.

17. The device of claim 12 wherein the conductive liquid has a specific resistance of from about 10⁶ to 10⁸ ohm-cm and a viscosity not greater than about 2 centipoise and the wire has a diameter not greater than about one-eighth of an inch.

18. The device of claim 12 wherein the conductive liquid has a specific resistance of from about 10⁶ to 10⁸ ohm-cm and a viscosity not greater than about 2 centipoise, the wire has a diameter not greater than about one-eighth of an inch and the resistance between electrodes is from about 5×

10⁴ to 5×

10⁵ ohms.

19. A device adapted to sensing motion when activated by passage of an electric current between two electrodes comprised of a cylindrical, sealed container partially filled with a mobile, conductive liquid with a specific resistance of from about 10⁶ to 10⁸ ohm-cm and a viscosity not greater than about 2 centipoise, said container providing one or two electrodes, the second electrode being a centrally positioned cylindrical wire with a diameter not greater than about one-eighth of an inch, the second electrode being only partially immersed in said conductive liquid, and the immersed portion of said second electrode receiving the electric current from above the surface of the liquid through a resistor the electrodes being made of a material selected from the group consisting of aluminum, copper, nickel and zinc and alloys of aluminum, of copper, of nickel and of zinc, and, where the resistance between the electrodes is from about 10³ to 10⁶ ohms.

20. The device of claim 19 wherein the resistance between the electrodes is from about 5×

10⁴ to about 10⁵ ohms.

21. The device of claim 19 wherein both electrodes are made of the same material.

23. The device of claim 19 wherein the electrodes are made of copper.

24. The device of claim 19 wherein the electrodes are made of brass.

25. The device of claim 19 wherein no dimension of the container is greater than about one inch, and both electrodes are made of the same material.

26. The device of claim 19 wherein no dimension of the container is greater than about 1 inch, and both electrodes are made of brass.

27. The device of claim 19 wherein no dimension of the container is greater than about 1 inch, and both electrodes are made of copper.

28. The device of claim 19 wherein no dimension of the container is greater than about one inch, both electrodes are made of brass, and the conductive liquid is commercial acetone.

29. The device of claim 19 wherein no dimension of the container is greater than about one inch, both electrodes are made of copper and the conductive liquid is commercial acetone.

30. The device of claim 19 wherein no dimension of the container is greater than about one inch, both electrodes are made of brass and the conductive liquid is 95% ethanol.

31. The device of claim 19 wherein no dimension of the container is greater than about one inch, both electrodes are made of copper and the conductive liquid is 95% ethanol.

22. The device of claim I9 wherein no dimension of the container is greater than about 1 inch.

32. A device adapted to sensing motion when activated by passing of an electric current between two electrodes comprised of a container partially filled with a mobile, conductive liquid and first and second electrodes in contact with said conductive liquid with at least said second electrode only partially immersed in said conductive liquid, the immersed portion of said second electrode receiving the electric current from above the surface of the liquid through a resistor and with the resistance between said electrodes being in the range from about 0.1 ohm to about 10⁷ ohms, means for passing an electric current through said electrodes, means for sensing the change in electric current when the resistance between the electrodes is changed by motion of the conductive liquid, signal means, and means for activating said signal means when the change in resistance is sensed by the sensing means.

33. The signal system of claim 32 wherein the motion sensing device is comprised of a cylindrical, sealed container partially filled with a conductive liquid with a specific resistance in the range from about 10⁶ to 10⁸ ohm-cm and a viscosity not greater than about 2 centipoise, said container providing one of two electrodes, the second electrode being a centrally positioned cylindrical wire with diameter not greater than about one-eighth of an inch, the second electrode being only partially immersed in said conductive liquid, the electrodes being made from a material selected from the group consisting of aluminum, copper, nickel and zinc and alloys of aluminum, of copper, of nickel and of zinc, both electrodes being made from the same material, and, where the resistance between the electrodes is about 100,000 ohms, means for passing a flow of electric current through said electrodes, means for sensing the change in electric current when the resistance between the electrodes is changed by motion of the conductive liquid, signal means, and means for activating said signal means when the change in resistance is sensed by the sensing means.