Patent US3868485A successfully refreshed from Google Patents.
US3868485A
Expired / Lapsed
US
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Density sensing probe switch with adjustable float
Assignee: Advanced Systems Inc
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Filing: 1972-09-07
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Granted: 1975-02-25
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Expires: 1992-09-07
Abstract
Abstract A density sensing probe for use in a bath for etching metal. The etching bath operates with its upper surface at a fixed level. As etching proceeds, dissolved metal added to the bath by the etching process increases the density of the bath. Too great an increase reduces etching efficiency. A density sensing probe maintains the density of the bath substantially constant. The probe includes a member the specific gravity of which is slightly greater than a preselected bath density so that the member will sink when the density of the bath is slightly less than the preselected density, but will rise when the density of the bath is slightly greater than the preselected density. When the member rises, such motion closes a switch that actuates circuitry for supplying a replenishing liquid to the bath, which replenishing liquid has a density less than the preselected density. Thus, the density of the bath is maintained at about the preselected density, increasing as more metal is etched and decreasing when the probe causes replenishing liquid to be added.
Inventors
- 👤 Donald J Sykes
- 👤 Elias Papaconstantinou
- 👤 Kenneth Murski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:44
CPC Classifications
G; G01; G01N; G01N9/00; G01N9/10; G01N9/12; G01N9/18; G01N9/16
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
181 words
A density sensing probe for controlling the operation of an electric device that maintains substantially constant density of a body of liquid the level of which is substantially constant, said probe comprising a support adapted to be at least partially disposed in the body of liquid, a body largely disposed below said support and in said liquid, means connecting said body to said support for guiding said body and its movement relative to said support, means to selectively adjust movement of the body in response to a change in the density of the liquid, said adjusting means being disposed on the periphery of the body, said periphery and said adjusting means including complimentary threaded portions, switch means responsive to a change in position of said body, an electrical device associated with said liquid the actuation of which reduces the density of the liquid, and circuit means connecting the switch means to the electrical device to actuate the electrical device when the body of liquid experiences an increase in density so as to lower the density and maintain the density substantially constant.
Claim 2
Dependent Claim
181 words
A density sensing probe for controlling the operation of an electric device that maintains substantially constant density of a body of liquid the level of which is substantially constant, said probe comprising a support adapted to be at least partially disposed in the body of liquid, a body largely disposed below said support and in said liquid, means connecting said body to said support for guiding said body and its movement relative to said support, means to selectively adjust movement of the body in response to a change in the density of the liquid, said adjusting means being disposed on the periphery of the body, said periphery and said adjusting means including complimentary threaded portions, switch means responsive to a change in position of said body, an electrical device associated with said liquid the actuation of which reduces the density of the liquid, and circuit means connecting the switch means to the electrical device to actuate the electrical device when the body of liquid experiences an increase in density so as to lower the density and maintain the density substantially constant.
Claim 3
Dependent Claim
18 words
A density sensing probe as set forth in claim 1 wherein the connecting means constitutes a horizontal axle.
Claim 4
Dependent Claim
57 words
A density sensing probe as set forth in claim 1 wherein the means responsive to a change in position of said body comprises a reed switch having a ferrous member and also comprises a permanent magnet member, one of said members being carried by said support and the other of said members being carried by said body.
Claim 5
Dependent Claim
35 words
A density sensing probe as set forth in claim 1 wherein the selective adjusting means includes means defining a space movable with the body and wherein the adjusting means adjusts the volume of such space.
Claim 6
Dependent Claim
66 words
A density sensing probe as set forth in claim 1 wherein the adjusting means includes a cap and means mounting the cap for telescopic movement relative to an end of the body without permitting entry of liquid into the cap whereby as the cap is moved toward and away from the body it varies the size of a space defined by the cap and the body.
Claim 7
Dependent Claim
60 words
A density sensing probe as set forth in claim 2 wherein the body is elongated and wherein the adjusting means includes a member having a specific gravity different from the specific gravity of the liquid, and means mounting the member for adjustable movement along the length of the body in a position at least partially submerged in the liquid body.
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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) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |