US3765244A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital readout instrument employing transducer and double d.c. power supply
Assignee: J Wagner AG
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Filing: 1971-04-19
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Granted: 1973-10-16
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Expires: 1991-04-19
Abstract
Abstract A digital readout thermometer employing a resistance bridge with a temperature sensitive resistance such as a thermistor in one leg of the bridge and including a motor driven adjustable resistance or potentiometer for rebalancing the bridge. A servo amplifier and d.c. servo motor servo drive a digital counter to provide a reading indicative of the temperature. The circuit employs a d.c. power supply for the bridge circuit and a second d.c. power supply cooperating with the first power supply for furnishing the servo circuit with opposite polarity voltages whereby the digital counter will operate in both directions.
Inventors
- 👤 J Brzezinski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:44
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/01; G; G01; G01K; G01K1/00; G01K1/02; G01K1/028; G01R; G01R17/00; G01R17/10; G01R17/105
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
269 words
A battery powered portable system for digitally displaying a measured parameter comprising: A transducer having electrical characteristics varying with the parameter to be measured; A rebalancing bridge including said transducer as the leg of said bridge; An adjustable leg of said bridge capable of rebalancing the bridge to compensate for variation in the bridge balance because of said transducer; A first battery; Means for applying the potential from said firsT battery across said bridge to provide operating potential therefore; An amplifier connected to said bridge to amplify the potential from said bridge related to the position of said adjustable leg of said bridge; A second battery; Means for applying power from said first and second batteries to said amplifier whereby said amplifier provides an output signal related in magnitude and polarity to the degree and direction of adjustment of said adjustable leg; Servo means driven by said amplifier including a digital display device for displaying a visual indication of the parameter measured by said transducer; Said servo means including a feedback connection between said servo means and said bridge to reduce the signal produced by said amplifier to substantially zero while said indicator matches in reading the parameter measured by said transducer; and Said first and second batteries connected to said servo means to drive said servo means; Including voltage regulator means for applying regulated potential from said first and second batteries comprising a pair of Zener diode networks furnishing regulated opposite potentials to said amplifier whereby the output of said amplifier is a function of the differential potential at its signal input and insensitive to supply potential variations.
Claim 2
Dependent Claim
269 words
A battery powered portable system for digitally displaying a measured parameter comprising: A transducer having electrical characteristics varying with the parameter to be measured; A rebalancing bridge including said transducer as the leg of said bridge; An adjustable leg of said bridge capable of rebalancing the bridge to compensate for variation in the bridge balance because of said transducer; A first battery; Means for applying the potential from said firsT battery across said bridge to provide operating potential therefore; An amplifier connected to said bridge to amplify the potential from said bridge related to the position of said adjustable leg of said bridge; A second battery; Means for applying power from said first and second batteries to said amplifier whereby said amplifier provides an output signal related in magnitude and polarity to the degree and direction of adjustment of said adjustable leg; Servo means driven by said amplifier including a digital display device for displaying a visual indication of the parameter measured by said transducer; Said servo means including a feedback connection between said servo means and said bridge to reduce the signal produced by said amplifier to substantially zero while said indicator matches in reading the parameter measured by said transducer; and Said first and second batteries connected to said servo means to drive said servo means; Including voltage regulator means for applying regulated potential from said first and second batteries comprising a pair of Zener diode networks furnishing regulated opposite potentials to said amplifier whereby the output of said amplifier is a function of the differential potential at its signal input and insensitive to supply potential variations.
Claim 3
Dependent Claim
25 words
The combination in accordance with claim 1 including means for applying unregulated opposed polarity power from said first and second batteries to said servo means.
Claim 4
Dependent Claim
209 words
A portable battery powered electronic thermometer comprising: a temperature sensitive resistance; a resistance bridge including said temperature sensitive resistance in one leg thereof; said bridge also including a potentiometer for balancing said bridge; first battery power supply means for applying a potential across said bridge; amplifier means connected to said balancing potentiometer for amplifying any bridge unbalance potential; a digital readout device connected to said amplifier means for recording a temperature as sensed by said temperature sensitive resistance as a measure of the balancing potentiometer position; motor means for driving said digital readout device; a feedback connection means between said motor means and said amplifier means for completing a servo loop between said balancing potentiometer and said digital readout device; means connecting said first power supply means to provide power to drive said motor means in one direction; and, second battery power supply means connected to said motor means for driving the readout device in the opposite direction; said first battery power supply means includes voltage regulator means for maintaining a substantially constant voltage across said bridge; and including amplifier means for amplifying a difference voltage related to the unbalance of the bridge wherein said first and second battery power supply means provide regulated voltage to said amplifier means.
Claim 5
Dependent Claim
209 words
A portable battery powered electronic thermometer comprising: a temperature sensitive resistance; a resistance bridge including said temperature sensitive resistance in one leg thereof; said bridge also including a potentiometer for balancing said bridge; first battery power supply means for applying a potential across said bridge; amplifier means connected to said balancing potentiometer for amplifying any bridge unbalance potential; a digital readout device connected to said amplifier means for recording a temperature as sensed by said temperature sensitive resistance as a measure of the balancing potentiometer position; motor means for driving said digital readout device; a feedback connection means between said motor means and said amplifier means for completing a servo loop between said balancing potentiometer and said digital readout device; means connecting said first power supply means to provide power to drive said motor means in one direction; and, second battery power supply means connected to said motor means for driving the readout device in the opposite direction; said first battery power supply means includes voltage regulator means for maintaining a substantially constant voltage across said bridge; and including amplifier means for amplifying a difference voltage related to the unbalance of the bridge wherein said first and second battery power supply means provide regulated voltage to said amplifier means.
Claim 6
Dependent Claim
218 words
A portable battery powered electronic thermometer comprising: a temperature sensitive resistance; a resistance bridge including said temperature sensitive in one leg thereof; said bridge also including a potentiometer for balancing said bridge; first battery power supply means for applying a potential across said bridge; amplifier means connected to said balancing potentiometer for amplifying any bridge unbalance potential; a digital readout device connected to said amplifier means for recording a temperature as sensed by said temperature sensitive resistance as a measure of the balancing potentiometer position; motor means for driving said digital readout device; a feedback connection means between said motor means and said amplifier means for completing a servo loop between said balancing potentiometer and said digital readout device; means connecting said first power supply means to provide power to drive said motor means in one direction; aNd, second battery power supply means connected to said motor means for driving the readout device in the opposite direction; wherein said first battery power supply means includes voltage regulator means for maintaining a substantially constant voltage across said bridge; wherein said second battery power supply means is connected to drive said servo motor fully in one direction in the absence of power from said first battery power supply means to indicate the inoperativeness of said first battery power supply means.
Claim 7
Dependent Claim
218 words
A portable battery powered electronic thermometer comprising: a temperature sensitive resistance; a resistance bridge including said temperature sensitive in one leg thereof; said bridge also including a potentiometer for balancing said bridge; first battery power supply means for applying a potential across said bridge; amplifier means connected to said balancing potentiometer for amplifying any bridge unbalance potential; a digital readout device connected to said amplifier means for recording a temperature as sensed by said temperature sensitive resistance as a measure of the balancing potentiometer position; motor means for driving said digital readout device; a feedback connection means between said motor means and said amplifier means for completing a servo loop between said balancing potentiometer and said digital readout device; means connecting said first power supply means to provide power to drive said motor means in one direction; aNd, second battery power supply means connected to said motor means for driving the readout device in the opposite direction; wherein said first battery power supply means includes voltage regulator means for maintaining a substantially constant voltage across said bridge; wherein said second battery power supply means is connected to drive said servo motor fully in one direction in the absence of power from said first battery power supply means to indicate the inoperativeness of said first battery power supply means.
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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) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |