US6000846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Medical thermometer
Assignee: Welch Allyn Inc
•
Filing: 1997-05-20
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Granted: 1999-12-14
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Expires: 2017-05-20
Abstract
Abstract An improved prediction-type medical thermometer that provides an accurate estimate of a patient's temperature in substantially reduced time as compared to prior thermometers of this kind. This improved performance is achieved by using a special hollow probe tip having a low heat capacity and incorporating a resistive heater that is actuated only upon removal of the probe from a base housing. In particular, a processor measures an initial temperature upon the probe's removal and applies to the heater an initial electrical signal having prescribed parameter, e.g., pulse duration, that varies according to the initial temperature measurement. This warms the probe to a prescribed temperature at or near about 93° F., after which the processor applies a sequence of pulses to the heater, to controllably regulate the probe's temperature to the prescribed value.
Inventors
- 👤 Thomas K. Gregory
- 👤 Kerry O. Banke
- 👤 John A. Mossman
- 👤 John W. Stevenson
- 👤 Edward D. Suszynski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 02:16
CPC Classifications
G; G01; G01K; G01K7/00; G01K7/42
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
135 words
A medical thermometer for measuring the temperature of a patient, comprising: a probe configured to be received by the patient; a temperature sensor, mounted in the probe, that provides a sensor signal indicating the temperature of the sensor; an electrical heater mounted in the probe, that warms the probe in response to an electrical signal; and a processor configured to measure an initial temperature at a start time, prior to receipt of the probe by the patient, and to apply to the electrical heater an initial electrical signal having a prescribed parameter that varies according to the initial temperature measurement and not according to any subsequent temperature measurement, wherein the prescribed parameter of the initial electrical signal is selected such that the probe is warmed to a temperature at or near a predetermined target temperature.
Claim 2
Dependent Claim
135 words
A medical thermometer for measuring the temperature of a patient, comprising: a probe configured to be received by the patient; a temperature sensor, mounted in the probe, that provides a sensor signal indicating the temperature of the sensor; an electrical heater mounted in the probe, that warms the probe in response to an electrical signal; and a processor configured to measure an initial temperature at a start time, prior to receipt of the probe by the patient, and to apply to the electrical heater an initial electrical signal having a prescribed parameter that varies according to the initial temperature measurement and not according to any subsequent temperature measurement, wherein the prescribed parameter of the initial electrical signal is selected such that the probe is warmed to a temperature at or near a predetermined target temperature.
Claim 3
Dependent Claim
32 words
A medical thermometer as defined in claim 1, wherein the electrical heater is separate from the temperature sensor and is mounted in the probe in a predetermined relationship to the temperature sensor.
Claim 4
Dependent Claim
65 words
A medical thermometer as defined in claim 1, wherein: the medical thermometer further comprises an electrical power source having a variable voltage; the processor further is configured to measure the voltage of the electrical power source; and the prescribed parameter of the initial electrical signal applied by the processor to the electrical heater varies according to both the initial temperature measurement and the voltage measurement.
Claim 5
Dependent Claim
30 words
A medical thermometer as defined in claim 1, wherein: the initial electrical signal is a substantially continuous pulse; and the prescribed parameter of the initial electrical signal is pulse duration.
Claim 6
Dependent Claim
35 words
A medical thermometer as defined in claim 1, wherein: the initial temperature measurement is a measurement of the temperature of the probe; and the processor produces the initial temperature measurement by measuring the sensor signal.
Claim 7
Dependent Claim
53 words
A medical thermometer as defined in claim 1, wherein the processor further is configured to repeatedly sample the sensor signal, after the initial electrical signal has ended, and to apply a prescribed temperature maintenance signal to the electrical heater, to controllably regulate the measured temperature of the probe to the predetermined target temperature.
Claim 8
Dependent Claim
42 words
A medical thermometer as defined in claim 6, wherein: the processor samples the sensor signal at regular time intervals; and the prescribed temperature maintenance signal applied to the electrical heater by the processor is a sequence of pulses having selected time durations.
Claim 9
Dependent Claim
48 words
A medical thermometer as defined in claim 6, wherein the prescribed temperature maintenance signal applied to the electrical heater after the initial electrical signal has ended varies according both to the most recent sample of the sensor signal and to the rate of change of the sensor signal.
Claim 10
Dependent Claim
55 words
A medical thermometer as defined in claim 8, wherein the prescribed temperature maintenance signal applied to the electrical heater after the initial electrical signal has ended further varies according to any difference between the temperature represented by the sensor signal, as determined immediately after the initial electrical signal has ended, and the predetermined target temperature.
Claim 11
Dependent Claim
51 words
A medical thermometer as defined in claim 1, wherein: the probe includes a hollow metallic tip; the temperature sensor is a thermistor bonded to an inside wall of the probe's hollow metallic tip; and the electrical heater is a resistor bonded to the inside wall of the probe's hollow metallic tip.
Claim 12
Dependent Claim
31 words
A medical thermometer as defined in claim 10, wherein the thermistor and the resistor are bonded to the inside wall of the probe's hollow metallic tip at substantially diametrically opposed positions.
Claim 13
Dependent Claim
40 words
A medical thermometer as defined in claim 1, wherein the processor further is configured to preliminarily calibrate the probe by applying to the electrical heater a calibration pulse of predetermined duration and measuring the resulting change in the sensor signal.
Claim 14
Dependent Claim
54 words
A medical thermometer as defined in claim 1, wherein: the thermometer is configured to measure patient temperatures in a repeated manner; and the processor further is configured to repeatedly calibrate the probe by comparing the temperature represented by the sensor signal, immediately after each initial electrical signal has ended, with the predetermined target temperature.
Claim 15
Dependent Claim
45 words
A medical thermometer as defined in claim 1, wherein the probe includes: an elongated base having a remote end; and a hollow metallic tip having a closed end and an open end sized to be attached securely to the remote end of the elongated base.
Claim 16
Dependent Claim
32 words
A medical thermometer as defined in claim 14, wherein the hollow metallic tip is formed of stainless steel and has a substantially uniform thickness less than or equal to about 0.1 millimeters.
Claim 17
Independent Claim
144 words
A method for measuring a patient's temperature using a medical thermometer of the kind having a probe, a temperature sensor mounted in the probe and configured to produce a sensor signal indicating the temperature of the sensor, and an electrical heater mounted in the probe and configured to warm the probe in response to an electrical signal, the method comprising: measuring an initial temperature at a start time, prior to receipt of the probe by the patient, to produce an initial temperature measurement; and applying an initial electrical signal to the electrical heater, wherein the initial electrical signal has a prescribed parameter that varies according to the initial temperature measurement but not according to any subsequent temperature measurement, and wherein the prescribed parameter of the initial electrical signal is selected to warm the probe to a temperature at or near a predetermined target temperature.
Claim 18
Independent Claim
144 words
A method for measuring a patient's temperature using a medical thermometer of the kind having a probe, a temperature sensor mounted in the probe and configured to produce a sensor signal indicating the temperature of the sensor, and an electrical heater mounted in the probe and configured to warm the probe in response to an electrical signal, the method comprising: measuring an initial temperature at a start time, prior to receipt of the probe by the patient, to produce an initial temperature measurement; and applying an initial electrical signal to the electrical heater, wherein the initial electrical signal has a prescribed parameter that varies according to the initial temperature measurement but not according to any subsequent temperature measurement, and wherein the prescribed parameter of the initial electrical signal is selected to warm the probe to a temperature at or near a predetermined target temperature.
Claim 19
Dependent Claim
64 words
A method as defined in claim 16, wherein: the medical thermometer further includes an electrical power source having a variable voltage; the method further comprises measuring the voltage of the electrical power source; and the prescribed parameter of the initial electrical signal applied to the electrical heater in the step of applying varies according to both the initial temperature measurement and the voltage measurement.
Claim 20
Dependent Claim
29 words
A method as defined in claim 16, wherein: the initial electrical signal is a substantially continuous pulse; and the prescribed parameter of the initial electrical signal is pulse duration.
Claim 21
Dependent Claim
31 words
A method as defined in claim 16, wherein: the initial temperature measurement is a measurement of the temperature of the probe; and the step of measuring includes measuring the sensor signal.
Claim 22
Dependent Claim
66 words
A method as defined in claim 16, and further comprising: repeatedly sampling the sensor signal, after the step of applying the initial electrical signal has ended; and applying a prescribed temperature maintenance signal to the electrical heater, after the step of applying the initial electrical signal has ended, to controllably regulate the temperature of the probe to a temperature at or near the predetermined target temperature.
Claim 23
Dependent Claim
54 words
A method as defined in claim 20, wherein: the step of repeatedly sampling occurs at regular time intervals; and the prescribed temperature maintenance signal applied to the electrical heater in the step of applying, after the step of applying the initial electrical signal has ended, is a sequence of pulses having selected time durations.
Claim 24
Dependent Claim
56 words
A method as defined in claim 20, wherein the prescribed temperature maintenance signal applied to the electrical heater in the step of applying, after the step of applying the initial electrical signal has ended, varies according both to the most recent sample of the sensor signal and to the rate of change of the sensor signal.
Claim 25
Dependent Claim
59 words
A method as defined in claim 20, wherein the prescribed temperature maintenance signal applied to the electrical heater, after the step of applying the initial electrical signal has ended, varies according to any difference between the temperature represented by the sensor signal, immediately after the step of applying the initial electrical signal has ended, and the predetermined target temperature.
Claim 26
Dependent Claim
38 words
A method as defined in claim 16, and further comprising a step of preliminarily calibrating the probe by applying to the electrical heater a calibration pulse of predetermined duration and measuring the resulting change in the sensor signal.
Claim 27
Dependent Claim
58 words
A method as defined in claim 16, wherein: the medical thermometer is configured to measure patient temperatures in a repeated manner; and the method further comprises calibrating the probe by comparing a step of the temperature represented by the sensor signal, immediately after the step of applying the initial electrical signal has ended, with the predetermined target temperature.
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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) | 2002-12-13 | 2003-06-14 | 2003-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-12-13 | 2007-06-14 | 2007-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-12-13 | 2011-06-14 | 2011-12-14 | $7700.00 | Window Closed / Lapsed |