US3790870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin oxide force sensitive switches
Assignee: Individual
•
Filing: 1971-03-11
•
Granted: 1974-02-05
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Expires: 1991-03-11
Abstract
Abstract A new class of bi-stable solid state switching devices, designated Force Switchable Diodes or FSD''s, are provided by copper/cuprous oxide rectifying or ''''blocking'''' junction devices, exemplified in elemental form by a copper substrate, a contacting thin cuprous oxide layer and the interface between them, such devices are arranged to avalanche from a blocking state to an essentially conducting state on the application of force when under a related voltage, and avalanche back to a blocking state on the removal of at least a portion of that force. The transition between the states is sharp, predictable and free of arcing effects. A single copper/cuprous oxide junction provides unidirectional switching, and an assembly comprising a set of copper/cuprous oxide/copper junctions provides bi-directional switching or polarity insensitivity. De-switching does not require a reduction of applied voltage, nor does switching require an increase in applied voltage. Force Switchable Diodes, however, provide an inverse relationship between switching force and voltage, and a positive relationship between switching force and thickness of the cuprous oxide layer. The invention provides for both discrete switches and integrated matrix switching arrays, and further comprises mechanical and electrochemical methods of forming blocking junctions.
Inventors
- 👤 R Mitchell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 17:21
CPC Classifications
H; H10; H10D; H10D48/00; H10D48/50
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
41 words
The invention as set forth in claim 1 above, wherein the switch is responsive to applied force of a predetermined amount, the force being determined as a function of the effective thickness of the cuprous oxide layer and the applied voltage.
Claim 2
Dependent Claim
25 words
The invention as set forth in claim 1 above, wherein said cuprous oxide element is of between approximately 0.0002 inch and 0.0006 inch in thickness.
Claim 3
Dependent Claim
32 words
The invention as set forth in claim 3 above, wherein the applied voltage is of the order of six volts and the applied force is of the order of a few ounces.
Claim 4
Dependent Claim
27 words
The invention as set forth in claim 1 above, wherein said switch comprises a single copper element, a single cuprous oxide element and a non-copper conductive element.
Claim 5
Dependent Claim
41 words
The invention as set forth in claim 1 above, wherein said switch comprises at least two regions separated from each other, each region having a copper strata and a cuprous oxide strata in facing and contacting relation defining a junction therebetween.
Claim 6
Dependent Claim
30 words
The invention as set forth in claim 6 above, wherein the free electron flow is in the same relative direction in each of the junctions and the switch is uni-directional.
Claim 7
Dependent Claim
29 words
The invention as set forth in claim 6 above, wherein the free electron flow is in opposite directions in different ones of the junctions and the switch is bi-directional.
Claim 8
Dependent Claim
29 words
The invention as set forth in claim 1 above, wherein said cuprous oxide element comprises a formed layer on said copper element and said formed layer is electrochemically reacted.
Claim 9
Dependent Claim
18 words
The invention as set forth in claim 1 above, wherein said cuprous oxide element comprises cuprous oxide powder.
Claim 10
Dependent Claim
180 words
A force switchable electrical device having substantially infinite resistance to electron flow in at least a given direction and permitting electron flow with very low voltage drop in said direction only in response to the application of mechanical force in excess of a predetermined amount comprising: a planar copper base member; a planar cuprous oxide layer member of less than approximately 0.0006 inch in thickness, said cuprous oxide layer being disposed in contiguous contacting relation to said copper base member and being in electrical circuit therewith at the interfacing junction therebetween, said given direction being from said cuprous oxide layer to said copper base member and said layer member being positioned to receive an applied force; and circuit means coupled to said base member and said layer member for establishing an electrical potential across said junction to provide electron flow in at least the given direction, wherein the effective thickness of said cuprous oxide layer is chosen relative to the applied voltage to switch to permit electron flow in response to forces of levels that may conveniently be manually exerted.
Claim 11
Dependent Claim
38 words
The invention as set forth in claim 11 above, wherein said cuprous oxide layer member is between approximately 0.0002 inch and 0.0006 inch in thickness, and wherein the electrical potential is in the range from approximately 5-32 volts.
Claim 12
Dependent Claim
59 words
A force switchable electrical element comprising: a conductive base member having a force bearing copper surface, a film of cuprous oxide oF less than 0.0001 inch in thickness, said cuprous oxide film being disposed upon the force bearing surface of said base member and being in electrical circuit therewith, and means disposed to seal said layer against further oxidation.
Claim 13
Dependent Claim
133 words
A solid state, bi-directional pressure device comprising: a substrate; a pair of thin, conductive coplanar electrodes disposed on said substrate and terminating in end portions separated by a non-conductive gap; a shunt electrode having a lower surface disposed upon said pair of electrodes and across the separation therebetween, said shunt electrode having an upper surface including a portion for receiving a mechanical force; a layer of cuprous oxide of less than approximately 0.001 inch in thickness and interposed between the lower surface of said shunt electrode and the facing surface of said pair of electrodes, at least one of said shunt electrode or said pair of electrodes being of copper; and sealant means disposed over said shunt electrode and said pair of electrodes to prevent oxidation and contamination of said cuprous oxide layer.
Claim 14
Dependent Claim
95 words
The invention as set forth in claim 14 above wherein said substrate comprises a printed circuit board, wherein the end portions of said pair of electrodes comprise half-disks separated by a gap at least several times the thickness of the layer of cuprous oxide, wherein the shunt electrode is a copper disk element of substantially the same size as said half-disk end portions, wherein said layer of cuprous oxide comprises a deposited layer of between approximately 0.0002 inch and 0.0006 inch in thickness, and wherein said pair of coplanar electrodes support a voltage difference therebetween.
Claim 15
Dependent Claim
170 words
A bi-state pressure responsive electrical switch comprising a rigid, hollow non-conductive housing having at least one open end; a first conductive electrode disposed within said housing in contact therewith and having at least a portion disposed adjacent said open end of said housing for receiving a mechanical force; first conductor means coupled through said housing to said first electrode; a second conductive electrode disposed within said housing and in contact therewith, said second electrode being separated from said first electrode by a gap; second conductor means coupled through said housing to said second electrode; and means including a copper strata and a cuprous oxide strata in facing contacting relation defining at least one junction interposed in the gap between said electrodes, and providing a planar surface area positioned to receive mechanical force exerted on said first electrode, the junction comprising a layer of cuprous oxide of less than approximately 0.0006 inch in thickness; and sealant means encompassing at least a portion of said housing to prevent oxidation and contamination therein.
Claim 16
Dependent Claim
31 words
The invention as set forth in claim 16 above, wherein said housing comprises an insulating member, and wherein the total cuprous oxide thickness is between approximately 0.0002 inch and 0.0006 inch.
Claim 17
Dependent Claim
25 words
The invention as set forth in claim 16 above, wherein said electrodes are copper and wherein said interposed member comprises a cuprous oxide barrier layer.
Claim 18
Dependent Claim
48 words
The invention as set forth in claim 16 above, wherein said electrodes are copper, and wherein said interposed member comprises a soft metal conductive disk having thin layers of cuprous oxide powder mechanically entrained therein on the opposite sides thereof, in facing contacting relation to said copper electrodes.
Claim 19
Dependent Claim
20 words
The invention as set forth in claim 19 above, wherein said soft metal conductor includes an internal hard conductive element.
Claim 20
Dependent Claim
49 words
The invention as set forth in claim 16 above, wherein one of said pair of electrodes is copper and the other is of a non-copper metal, and wherein said copper electrode includes, at the gap region in contact with the other electrode, a thin layer of cuprous oxide material.
Claim 21
Dependent Claim
45 words
The invention as set forth in claim 16 above, wherein at least one copper disk is interposed in the gap between said electrodes, the opposite faces of each of said copper disks comprising a layer of cuprous oxide of between 0.0001 inch and 0.0006 inch.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |