US3890478A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid level sensor
Assignee: Motors Liquidation Co
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Filing: 1973-11-07
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Granted: 1975-06-17
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Expires: 1993-11-07
Abstract
Abstract A liquid level sensor for a tank having a base member supporting a terminal member insulated therefrom and an arm with float attached at one end which is movable in response to changes in the liquid level of the tank to cause the arm''s other end to operably engage the terminal member to complete an electrical warning circuit. A coil type spring normally supports the arm in a neutral position which corresponds to a full tank. When the liquid level decreases, the coil spring is deflected to allow the arm to establish a connection between the terminal and the base of the sensor which is grounded.
Inventors
- 👤 John W Riddel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:57
CPC Classifications
H; H01; H01H; H01H35/00; H01H35/18
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
230 words
A liquid level sensor for a fluid containing tank comprising: a base member adapted to be supported by a tank wall; an insulating member supported by said base; a terminal member extending through said insulating member and having a first end portion extending outside the tank wall and adapted to be connected to an external low level indicator and a second end portion on an opposite side of said insulating member; an arm extending from said base member into said tank interior; float means in said tank interior attached to one end of said arm to produce movements of said arm in response to changes in the liquid level in the tank; a coil spring with a first end attached to said base member and a second end within the tank and operably supporting said arm to provide a resilient connection between said base member and said arm whereby movement of said float means due to a predetermined drop in the liquid level causes said arm to laterally deflect the second end of said spring in one direction and thereby cause movement of the other end of said arm in a second opposite direction; cup-shaped contact means supported between the second end portion of said terminal member and the other end of said arm for making an electrical connection therebetween by contact with the inner cylindrical surface of the contact.
Claim 2
Dependent Claim
230 words
A liquid level sensor for a fluid containing tank comprising: a base member adapted to be supported by a tank wall; an insulating member supported by said base; a terminal member extending through said insulating member and having a first end portion extending outside the tank wall and adapted to be connected to an external low level indicator and a second end portion on an opposite side of said insulating member; an arm extending from said base member into said tank interior; float means in said tank interior attached to one end of said arm to produce movements of said arm in response to changes in the liquid level in the tank; a coil spring with a first end attached to said base member and a second end within the tank and operably supporting said arm to provide a resilient connection between said base member and said arm whereby movement of said float means due to a predetermined drop in the liquid level causes said arm to laterally deflect the second end of said spring in one direction and thereby cause movement of the other end of said arm in a second opposite direction; cup-shaped contact means supported between the second end portion of said terminal member and the other end of said arm for making an electrical connection therebetween by contact with the inner cylindrical surface of the contact.
Claim 3
Dependent Claim
262 words
A liquid level sensor for a fluid containing tank comprising: a base member adapted to be supported by a tank wall; an insulating member supported by said base member; terminal means extending through said insulating member and having a first end portion extending outside the tank wall and adapted to be connected to an external low level indicator and a second end portion on an opposite side of said insulating member; an arm extending away from said base member into said tank interior; float means in the tank interior attached to one end of said arm to produce movements of said arm in response to changes in the liquid level in the tank; diaphragm means attached at a peripheral edge to said base member and engaging a mid-portion of said arm to provide a resilient connection between said base and said arm; a pin extending through said diaphragm means and said arm to permit pivotal movement thereabout; a coil spring with a first end attached to said base and a second end operably attached to the other end of said arm whereby movement of said float means due to a predetermined drop in the liquid level causes said arm to pivot around said pin and move the other end of said arm while laterally deflecting the second end of said spring; cup-shaped contact means supported between the second end portion of said terminal member and the other end of said arm for making an electrical connection between said terminal and said base by contact with the inner cylindrical surface of the contact.
Claim 4
Dependent Claim
262 words
A liquid level sensor for a fluid containing tank comprising: a base member adapted to be supported by a tank wall; an insulating member supported by said base member; terminal means extending through said insulating member and having a first end portion extending outside the tank wall and adapted to be connected to an external low level indicator and a second end portion on an opposite side of said insulating member; an arm extending away from said base member into said tank interior; float means in the tank interior attached to one end of said arm to produce movements of said arm in response to changes in the liquid level in the tank; diaphragm means attached at a peripheral edge to said base member and engaging a mid-portion of said arm to provide a resilient connection between said base and said arm; a pin extending through said diaphragm means and said arm to permit pivotal movement thereabout; a coil spring with a first end attached to said base and a second end operably attached to the other end of said arm whereby movement of said float means due to a predetermined drop in the liquid level causes said arm to pivot around said pin and move the other end of said arm while laterally deflecting the second end of said spring; cup-shaped contact means supported between the second end portion of said terminal member and the other end of said arm for making an electrical connection between said terminal and said base by contact with the inner cylindrical surface of the contact.
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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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |