US4525125A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure responsive pump control system having an alarm lamp
Assignee: Mitsubishi Electric Corp
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Filing: 1983-12-06
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Granted: 1985-06-25
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Expires: 2003-12-06
Abstract
Abstract A pump control system has a vacuum pump driven by a DC motor to supply a negative pressure to a container first power and driving transistors which are interconnected to energize the DC motor, second power and driving transistors which are interconnected to turn an alarm lamp on, and a pressure sensor having a set of normally closed contacts which are connected to the first driving transistor and which are connected via a Zener diode to the second driving transistor; the contacts opened by at least a predetermined negative pressure within the container so as to immediately turn the first power transistor off and so as the second power transistor off with a time delay as determined by a parallel combination of a capacitor and a resistor connected to the Zener diode.
Inventors
- 👤 Akio Matsumoto
- 👤 Mitsuyoshi Yokota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 08:05
CPC Classifications
H; H02; H02H; H02H7/00; H02H7/08; H02H7/0811
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
124 words
A pump control system comprising a DC motor, a pump driven by said DC motor to generate and supply a pressure to a container, a single pressure sensor for sensing a pressure within said container controlled by said pump, and being operative with a predetermined pressure within said container, a first circuit means responsive to the operation of said single pressure sensor to drive said DC motor, a timing, circuit controlled in response to the operation of said single pressure sensor, an alarm lamp, and a circuit means responsive to an output from said timing circuit means to control the turn-on and -off of said alarm lamp whereby said single pressure sensor provides the sole means for controlling said pump and said alarm lamp.
Claim 2
Dependent Claim
124 words
A pump control system comprising a DC motor, a pump driven by said DC motor to generate and supply a pressure to a container, a single pressure sensor for sensing a pressure within said container controlled by said pump, and being operative with a predetermined pressure within said container, a first circuit means responsive to the operation of said single pressure sensor to drive said DC motor, a timing, circuit controlled in response to the operation of said single pressure sensor, an alarm lamp, and a circuit means responsive to an output from said timing circuit means to control the turn-on and -off of said alarm lamp whereby said single pressure sensor provides the sole means for controlling said pump and said alarm lamp.
Claim 3
Dependent Claim
28 words
A pump control system as claimed in claim 1 wherein said pump comprises a vacuum pump and said single pressure sensor senses a negative pressure in said container.
Claim 4
Dependent Claim
173 words
A pump control system comprising a DC motor, a pump driven by said DC motor to generate and supply a pressure to a container, a single pressure sensor for sensing a pressure within said container controlled by said pump, said single pressure sensor being operative in response to a predetermined pressure within said container sensed thereby, an indicating means for indicating that said container is under a pressure not higher than said predetermined pressure, a first switching element serially connected to said pump and responsive to a pressure within said container not less than said predetermined pressure as sensed by said single pressure sensor to be turned off, a second switching element serially connected to said indicating means and responsive to a pressure within said container not less than said predetermined pressure as sensed by said single pressure sensor to be turned off and a timing circuit for delaying the turn-off of said second switching element whereby said single pressure sensor provides the sole means for controlling said pump and said indicating means.
Claim 5
Dependent Claim
173 words
A pump control system comprising a DC motor, a pump driven by said DC motor to generate and supply a pressure to a container, a single pressure sensor for sensing a pressure within said container controlled by said pump, said single pressure sensor being operative in response to a predetermined pressure within said container sensed thereby, an indicating means for indicating that said container is under a pressure not higher than said predetermined pressure, a first switching element serially connected to said pump and responsive to a pressure within said container not less than said predetermined pressure as sensed by said single pressure sensor to be turned off, a second switching element serially connected to said indicating means and responsive to a pressure within said container not less than said predetermined pressure as sensed by said single pressure sensor to be turned off and a timing circuit for delaying the turn-off of said second switching element whereby said single pressure sensor provides the sole means for controlling said pump and said indicating means.
Claim 6
Dependent Claim
23 words
A pump control system as claimed in claim 3 wherein said second switching element includes an input circuit provided with a Zener diode.
Claim 7
Dependent Claim
23 words
A pump control system as claimed in claim 3 wherein said timing circuit includes a parallel combination of a capacitor and a resistor.
Claim 8
Dependent Claim
28 words
A pump control system as claimed in claim 2 wherein said pump comprises a vacuum pump and said single pressure sensor senses a negative pressure in said container.
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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) | 1988-06-24 | 1988-12-24 | 1989-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-24 | 1992-12-24 | 1993-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-24 | 1996-12-24 | 1997-06-25 | $7700.00 | Window Closed / Lapsed |