# US 2009/0260242 A1 · Integral electrode tilt sensor and method for making same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2009/0260242 A1 - Document ID: US20090260242A1 - Status: Published application - Kind: A1 - Application number: 12/380,865 - Filed: 2009-03-04 - Published: 2009-10-22 - Earliest claimed: 2008-03-05 - Assignees: The Fredericks Company - Inventors: Andrew Ruether; Joseph J. Seipp, JR. - Web page: https://patentgrep.com/patent/US20090260242A1 ## CPC - G01C 9/26: Details - G01C 9/34: of the tubular type, i.e. for indicating the level in one direction only - Y10T 29/49117: Conductor or circuit manufacturing - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Fabrication methods are provided for an electrolytic tilt sensor which includes a containment envelope defining an interior space; at least first and second electrodes disposed along, and in contact with, a first interior surface portion of the containment envelope, said first and second electrodes being spaced apart from each other to define a gap between respective opposing edges of the first and second electrodes; at least a third electrode disposed along and in contact with a second interior surface portion of the containment envelope opposite said first interior surface portion; an electrolyte solution at least partially filling the interior space of the containment envelope to provide a bubble; and means for hermetically sealing the containment envelope. ## Claims ### Claim 1 An electrolytic tilt sensor which comprises: a) a containment envelope defining an interior space; b) at least first and second electrodes disposed along, and in contact with, a first interior surface portion of the containment envelope, said first and second electrodes being spaced apart from each other to define a gap between respective opposing edges of the first and second electrodes; c) at least a third electrode disposed along and in contact with a second interior surface portion of the containment envelope opposite said first interior surface portion; d) an electrolyte solution at least partially filling the interior space of the containment envelope to provide a bubble; and e) means for hermetically sealing the containment envelope. ### Claim 2 (depends on 1) The electrolytic tilt sensor of claim 1 wherein the containment envelope comprises a curved glass tube. ### Claim 3 (depends on 1) The electrolytic tilt sensor of claim 1 wherein the first, second and third electrodes are coated onto the respective interior surface portions of the containment envelope. ### Claim 4 (depends on 1) The electrolytic tilt sensor of claim 1 wherein the first, second and third electrodes are fabricated from metals selected from the group consisting of platinum, palladium, iridium, ruthenium, osmium, rhodium, gold, silver, nickel, chromium, iron, alloys containing same and physical combinations thereof. ### Claim 5 (depends on 1) The electrolytic tilt sensor of claim 1 wherein the first, second and third electrodes are shaped by laser cutting. ### Claim 6 (depends on 1) The electrolytic tilt sensor of claim 1 wherein the electrolyte solution includes one or more cations of sodium, potassium, lithium, cesium and/or calcium, one or more anions of nitrate, carbonate, acetate and/or hydroxide, halogen, and one or more solvents including methanol, ethanol, butanol, propanol, isopropanol, acetone, methylethylketone, esters, butyl carbitol, butyl cellusolve, 2-methoxyethanol and/or methyl carbitol. ### Claim 7 (depends on 1) The electrolytic tilt sensor of claim 1 wherein the means for hermetically sealing the containment envelope comprises at least one end cap engaged at and sealing an open end of the containment envelope and affixed thereto with glass frit. ### Claim 8 (depends on 1) The electrolytic tilt sensor of claim 1 further including a plurality of conductive termination pads disposed around respective edges of the containment envelope and being in electrical contact with respective electrodes and providing means exterior to the containment envelope for electrical contact with an electrical circuit. ### Claim 9 (depends on 1) The electrolytic tilt sensor of claim 1 wherein the containment envelope includes a filling spout. ### Claim 10 (depends on 7) The electrolytic tilt sensor of claim 7 wherein the at least one end cap includes a channel for the introduction of electrolyte into the containment envelope. ### Claim 11 A method for making an electrolytic tilt sensor comprising the steps of: a) forming a containment envelope having an arcuate shape; b) attaching termination pads to respective edges of the containment vessel; c) disposing at least first and second electrodes along, and in contact with, a first interior surface portion of the containment envelope, said first and second electrodes being spaced apart from each other to define a gap between respective opposing edges of the first and second electrodes; d) disposing at least a third electrode along and in contact with a second interior surface portion of the containment envelope opposite said first interior surface portion; e) at least partially filling the containment envelope with an electrolyte solution to provide a gaseous bubble therein; f) sealing the containment envelope. ### Claim 12 (depends on 11) The method of claim 11 wherein the step (a) of forming the containment vessel comprises heating and bending a glass tube to a predetermined radius of curvature. ### Claim 13 (depends on 11) The method of claim 11 wherein the step (b) of attacking the termination pads comprises applying a frit of silver, gold, platinum, palladium, iridium, ruthenium, osmium, rhodium, or alloy thereof to edges of the containment vessel so as to overlap both exterior and interior surfaces of the containment vessel. ### Claim 14 (depends on 11) The method of claim 11 wherein the step (c) of disposing the first and second electrodes along the interior surface portion of the containment envelope comprises spraying a fritted glass paint containing a conductive metal to the interior surface of the containment envelope to provide a green coating, firing followed by laser cutting the coating to a desired shape, and firing the coating to provide the first and second conductive electrodes bonded to the containment envelope. ### Claim 15 (depends on 11) The method of claim 11 wherein the step (c) of disposing the first and second electrodes along the interior surface portion of the containment envelope comprises applying a rough shaped precious metal glass decal to the interior surface portion, firing, and laser trimming to form a more precisely shaped electrode. ### Claim 16 (depends on 11) The method of claim 11 wherein the step (c) of disposing the first and second electrodes along the interior surface portion of the containment envelope comprises applying a precisely shaped precious metal glass decal to the interior surface portion, and firing to form a precisely shaped electrode. ### Claim 17 (depends on 14) The method of claim 14 wherein the first and second electrodes are cut to form planar strips spaced apart from each other to define a gap between respective opposing edges of the first and second electrodes. ### Claim 18 (depends on 14) The method of claim 14 wherein the interior surface of the containment envelope is totally coated and the first and second electrodes are formed as rectangular island-shaped lines laser cut from the totally coated interior containment envelope. ### Claim 19 (depends on 11) The method of claim 11 wherein the step (c) of disposing the first and second electrodes along the interior surface of the containment envelope comprises filling the containment envelope with fritted glass paint containing a conductive metal, then draining the paint to provide a green coating, cutting the coating to a desired shape, and firing the coating to provide the first and second conductive electrodes bonded to the containment vessel. ### Claim 20 (depends on 19) The method of claim 19 wherein the first and second electrodes are cut to form planar strips spaced apart from each other to define a gap between respective opposing edges of the first and second electrodes. ### Claim 21 (depends on 19) The method of claim 19 wherein the interior surface of the containment envelope is totally coated and the first and second electrodes are formed as rectangular island-shaped lines laser cut from the totally coated interior containment envelope. ### Claim 22 (depends on 11) The method of claim 11 wherein the containment envelope has a pour spout and the step (e) of partially filling the containment envelope comprises introducing the electrolyte through the pour spout, and thereafter sealing the pour spout. ### Claim 23 (depends on 11) The method of claim 11 wherein the tilt sensor includes at least one end cap. ### Claim 24 (depends on 21) The method of claim 21 wherein the at least one end cap includes a fill channel and the step (e) of partially filling the containment envelope comprises introducing the electrolyte through the fill channel, then plugging the fill channel. ### Claim 25 (depends on 11) The method of claim 11 wherein sealing the containment envelope comprises securing fritted end caps to open ends of the glass envelope, then firing the tilt sensor to melt or soften the frit to provide a sealed joint. ### Claim 26 (depends on 11) The method of claim 11 further comprising attaching electrical lead wires to respective termination pads.