US3729998A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic, digital thermometer
Assignee: Royal Medical Corp
•
Filing: 1970-08-10
•
Granted: 1973-05-01
•
Expires: 1990-08-10
Abstract
Abstract An electronic thermometer having a probe for insertion into the mouth or other cavity where temperature is to be measured; disposable probe sheaths that are easily assembled with and removed from the probe; an electronics system comprising means for preheating the mouthward end of the probe, thus achieving very quick temperature measurement; and a digital temperature indicator. The invention includes means for quickly disengaging the disposable sheath from the probe and means for supporting the assembly on a nurse''s hospital board or from a neck strap. The electric circuitry receives power from batteries that are permanently fixed to a removable and quickly replaceable bottom (back) cover of the case.
Inventors
- 👤 F Mueller
- 👤 B Martin
- 👤 J Chandler
- 👤 R Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:35
CPC Classifications
G; G01; G01K; G01K7/00; G01K7/42; G01K13/00; G01K13/20
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
200 words
An electronic thermometer for measuring the temperature of an object, comprising: a source of electric current; temperature sensitive means attached to said probe for measuring the temperature of the probe and of said object and supplying an electric signal voltage proportional to the temperature; an amplifier, connected to said temperature sensitive means, receiving and amplifying said signal voltage; probe-preheating resistance means, attached to said probe; a preheating circuit electrically connected to said source, to said probe-preheating means and to said amplifier, comprising a differential amplifier for supplying preheating current to said probe-preheating means; means electrically connecting one input of said differential amplifier with said first-named amplifier, comprising electrical resistance; means, comprising electrical resistance, for supplying a comparison voltage to the other input of said differential amplifier; temperature-indicating means, comprising a counter, activated by electric pulses; means for producing a number of pulses and supplying them to the said counter, said number depending on the magnitude of the voltage output from said first-named amplifier when the said signal voltage is at its maximum value, stabilized with the stabilization of said temperature; and means for ceasing the supply of said pulses to the counter when said voltage is at its maximum value.
Claim 2
Dependent Claim
200 words
An electronic thermometer for measuring the temperature of an object, comprising: a source of electric current; temperature sensitive means attached to said probe for measuring the temperature of the probe and of said object and supplying an electric signal voltage proportional to the temperature; an amplifier, connected to said temperature sensitive means, receiving and amplifying said signal voltage; probe-preheating resistance means, attached to said probe; a preheating circuit electrically connected to said source, to said probe-preheating means and to said amplifier, comprising a differential amplifier for supplying preheating current to said probe-preheating means; means electrically connecting one input of said differential amplifier with said first-named amplifier, comprising electrical resistance; means, comprising electrical resistance, for supplying a comparison voltage to the other input of said differential amplifier; temperature-indicating means, comprising a counter, activated by electric pulses; means for producing a number of pulses and supplying them to the said counter, said number depending on the magnitude of the voltage output from said first-named amplifier when the said signal voltage is at its maximum value, stabilized with the stabilization of said temperature; and means for ceasing the supply of said pulses to the counter when said voltage is at its maximum value.
Claim 3
Dependent Claim
22 words
A thermometer as set forth in claim 1, in which the probe''s preheated temperature is below the average temperature of said object.
Claim 4
Dependent Claim
18 words
A thermometer as set forth in claim 1, in which said probe-preheated resistance means is a second thermistor.
Claim 5
Dependent Claim
19 words
A thermometer as set forth in claim 1, comprising a disposable sheath adapted to fit over the said probe.
Claim 6
Dependent Claim
17 words
A thermometer as set forth in claim 4, in which said disposable sheath is of resilient material.
Claim 7
Dependent Claim
145 words
An electronic thermometer comprising a source of electric current; a probe adapted to be positioned relative to an object for measurement of its temperature, comprising resistance heating means for preheating the probe to a predetermined temperature before said measurement, and a measuring thermistor in an end portion of the probe, for measuring said temperature and supplying a signal voltage proportional to the temperature; means actuated by said signal voltage for indicating the state of said temperature; and a preheating electrical circuit for supplying preheating current to said resistance heating means, comprising: electrical conducting means connected to said source of current; a switch; resistance means for determining a comparison voltage; a differential amplifier for comparing said comparison voltage and said signal voltage and supplying a current proportional to the difference between these two voltages; and conducting means transmitting said preheating current to said resistance heating means.
Claim 8
Dependent Claim
145 words
An electronic thermometer comprising a source of electric current; a probe adapted to be positioned relative to an object for measurement of its temperature, comprising resistance heating means for preheating the probe to a predetermined temperature before said measurement, and a measuring thermistor in an end portion of the probe, for measuring said temperature and supplying a signal voltage proportional to the temperature; means actuated by said signal voltage for indicating the state of said temperature; and a preheating electrical circuit for supplying preheating current to said resistance heating means, comprising: electrical conducting means connected to said source of current; a switch; resistance means for determining a comparison voltage; a differential amplifier for comparing said comparison voltage and said signal voltage and supplying a current proportional to the difference between these two voltages; and conducting means transmitting said preheating current to said resistance heating means.
Claim 9
Dependent Claim
41 words
A thermometer as set forth in claim 6, in which said second-named resistance means comprises two resistors and the said preheating circuit comprises a conductor, connected to and between said resistors, for conducting current from the resistors to said differential amplifier.
Claim 10
Dependent Claim
22 words
A thermometer as set forth in claim 7 in which said second-named resistance means comprises a potentiometer, for adjusting said comparison voltage.
Claim 11
Dependent Claim
33 words
A thermometer as set forth in claim 6, in which said differential amplifier comprises: a pair of transistors; a line connected to and between said transistors; and a resistor connected to said line.
Claim 12
Dependent Claim
39 words
A thermometer as set forth in claim 9, in which said differential amplifier has an output connection, and said preheating circuit comprising transistor means, connected to said output connection, to increase the amperage of the current from said connection.
Claim 13
Dependent Claim
27 words
A thermometer as set forth in claim 10, comprising means, connected to said output connection and to said transistor means, to predetermine the said increase of amperage.
Claim 14
Dependent Claim
22 words
A thermometer as set forth in claim 11, in which said resistance heating means is a second thermistor, mounted on said probe.
Claim 15
Dependent Claim
33 words
A thermometer as set forth in claim 6, comprising a second, temperature-measuring-circuit switch, and means for turning off one of said switches and turning on the other switch, substantially at the same time.
Claim 16
Dependent Claim
18 words
A thermometer as set forth in claim 6, comprising a disposable sheath, adapted to fit over said probe.
Claim 17
Dependent Claim
173 words
An electronic thermometer, comprising: a probe element adapted to be positioned adjacent to an object for measurement of its temperature, having a free end portion and a channel terminating at said free end portion; electric wiring in said channel; an element of heat-conducting metal, fixed to said free end portion; a probe-preheating thermistor, fixed to said metal element, connected to part of said wiring; a temperature-sensing thermistor, fixed to said metal element, connected to a second part of said wiring, supplying a signal voltage that is substantially proportional to the temperature of said probe; electrical means connected to and supplying probe-preheating current to said first-named wiring part and to said preheating thermistor, comprising: a differential amplifier connected to said first and second wiring parts; means for supplying a comparison voltage to said differential amplifier; and electrical resistance means for limiting said probe-preheating current to a desired amperage; and temperature-measuring and indicating means electrically connected to said second wiring part, for receiving said signal voltage and converting it into indication of degrees of temperature.
Claim 18
Dependent Claim
173 words
An electronic thermometer, comprising: a probe element adapted to be positioned adjacent to an object for measurement of its temperature, having a free end portion and a channel terminating at said free end portion; electric wiring in said channel; an element of heat-conducting metal, fixed to said free end portion; a probe-preheating thermistor, fixed to said metal element, connected to part of said wiring; a temperature-sensing thermistor, fixed to said metal element, connected to a second part of said wiring, supplying a signal voltage that is substantially proportional to the temperature of said probe; electrical means connected to and supplying probe-preheating current to said first-named wiring part and to said preheating thermistor, comprising: a differential amplifier connected to said first and second wiring parts; means for supplying a comparison voltage to said differential amplifier; and electrical resistance means for limiting said probe-preheating current to a desired amperage; and temperature-measuring and indicating means electrically connected to said second wiring part, for receiving said signal voltage and converting it into indication of degrees of temperature.
Claim 19
Dependent Claim
137 words
An electronic thermometer comprising: a probe adapted to be positioned adjacent an object for measuring its temperature, comprising: an elongated probe element; a metal, heat-conducting element attached to a free end of said elongated probe element; temperature-sensing electrical resistance means, fixed to said metal element, supplying a signal voltage that is proportional to the temperature of said probe; and probe-preheating resistance means, fixed to said metal element; electrical means connected to and supplying probe-preheating current to said probe-preheating resistance means, comprising a differential amplifier, with one input connected to said probe-preheating thermistor and the output connected to said temperature-sensing therMistor, and means for supplying a comparison voltage to the other input of said differential amplifier; temperature-measuring-and-indicating means, electrically connected to said temperature-sensing resistance means, for receiving said voltage and converting it into indication of degrees of temperature.
Claim 20
Dependent Claim
137 words
An electronic thermometer comprising: a probe adapted to be positioned adjacent an object for measuring its temperature, comprising: an elongated probe element; a metal, heat-conducting element attached to a free end of said elongated probe element; temperature-sensing electrical resistance means, fixed to said metal element, supplying a signal voltage that is proportional to the temperature of said probe; and probe-preheating resistance means, fixed to said metal element; electrical means connected to and supplying probe-preheating current to said probe-preheating resistance means, comprising a differential amplifier, with one input connected to said probe-preheating thermistor and the output connected to said temperature-sensing therMistor, and means for supplying a comparison voltage to the other input of said differential amplifier; temperature-measuring-and-indicating means, electrically connected to said temperature-sensing resistance means, for receiving said voltage and converting it into indication of degrees of temperature.
Claim 21
Dependent Claim
159 words
An electronic thermometer, comprising: a probe element adapted to be positioned adjacent to an object for measurement of its temperature, having a free end portion and a channel terminating at said free end portion; electric wiring in said channel; an element of heat-conducting metal, fixed to said free end portion; a probe-preheating thermistor, fixed to said metal element, connected to part of said wiring; a temperature-sensing thermistor, fixed to said metal element, connected to a second part of said wiring, supplying a signal voltage that is substantially proportional to the temperature of said probe; electrical means, connected to and supplying probe-preheating current to said first-named wiring part and to said preheating thermistor, comprising means for reducing the magnitude of said preheating current as the preheated temperature of said probe approaches a predetermined state; and temperature-measuring and indicating means electrically connected to said second wiring part, for receiving said signal voltage and converting it into indication of degrees of temperature.
Claim 22
Dependent Claim
159 words
An electronic thermometer, comprising: a probe element adapted to be positioned adjacent to an object for measurement of its temperature, having a free end portion and a channel terminating at said free end portion; electric wiring in said channel; an element of heat-conducting metal, fixed to said free end portion; a probe-preheating thermistor, fixed to said metal element, connected to part of said wiring; a temperature-sensing thermistor, fixed to said metal element, connected to a second part of said wiring, supplying a signal voltage that is substantially proportional to the temperature of said probe; electrical means, connected to and supplying probe-preheating current to said first-named wiring part and to said preheating thermistor, comprising means for reducing the magnitude of said preheating current as the preheated temperature of said probe approaches a predetermined state; and temperature-measuring and indicating means electrically connected to said second wiring part, for receiving said signal voltage and converting it into indication of degrees of temperature.
Claim 23
Dependent Claim
42 words
A thermometer as set forth in claim 17, comprising a probe-element sheath, in which an inward part of said probe element comprises a handle portion; and stop means at said handle portion, adapted to engage and stop assembling movement of said sheath.
Claim 24
Dependent Claim
90 words
A thermometer as set forth in claim 18, in which: the said probe-element sheath has a resilient portion and when not on the probe has a length less than the distance between said stop means and the outermost tip part of the probe element; the said resilient portion allows stretching of the sheath until its inward end abuts said stop means; and said probe element comprises means at said handle portion for detachably holding said inward end in place on the probe element, against the resiliency of said resilient portion.
Claim 25
Dependent Claim
141 words
An electronic thermometer comprising: a probe for measurement of the temperature of an object, comprising temperature-sensing means in an end portion of the probe, for measuring said temperature and supplying signal voltage proportional to the temperature; a probe sheath, adapted to fit over said probe having an open end portion adapted to move over the free end of the probe in assembly of the probe and sheath; means for supplying electric current to said temperature-sensing means; and means actuated by the said signal voltage for indicating the state of said temperature; the said probe having a handle portion; and an adjacent sheath-moving means, manually movable relative to the probe and to the sheath, and having a sheath-contacting-part and means responsive to movement of said sheath moving means toward said end portion of the probe to dislodge the sheath from said probe.
Claim 26
Dependent Claim
141 words
An electronic thermometer comprising: a probe for measurement of the temperature of an object, comprising temperature-sensing means in an end portion of the probe, for measuring said temperature and supplying signal voltage proportional to the temperature; a probe sheath, adapted to fit over said probe having an open end portion adapted to move over the free end of the probe in assembly of the probe and sheath; means for supplying electric current to said temperature-sensing means; and means actuated by the said signal voltage for indicating the state of said temperature; the said probe having a handle portion; and an adjacent sheath-moving means, manually movable relative to the probe and to the sheath, and having a sheath-contacting-part and means responsive to movement of said sheath moving means toward said end portion of the probe to dislodge the sheath from said probe.
Claim 27
Dependent Claim
22 words
An electronic thermometer as set forth in claim 20, in which said probe provides slide-bearing means for movement of said sheath-moving means.
Claim 28
Dependent Claim
38 words
A thermometer as set forth in claim 20, in which an outward, tip part of said probe sheath comprises a relatively thin wall of resilient plastic, and an inward part of said sheath comprises a relatively thick wall.
Claim 29
Dependent Claim
17 words
A thermometer as set forth in claim 20, in which the said thick wall is of plastic.
Claim 30
Dependent Claim
44 words
A thermometer as set forth in claim 20 in which said probe sheath compositely comprises two aligned parts and bonding material between adjacent end portions of said parts, and in which at least the outward one of said parts is of said resilient plastic.
Claim 31
Dependent Claim
17 words
A thermometer as set forth in claim 20, in which said probe sheath is of integral plastic.
Claim 32
Dependent Claim
23 words
A thermometer as set forth in claim 25, in which said probe sheath comprisEs an outward thin-wall part and an inward thick-wall part.
Claim 33
Dependent Claim
78 words
A thermometer as set forth in claim 20 in which said sheath-moving means comprises: a socket in said handle portion; a sliding element reciprocable in the general direction of the probe axis, connected to said sheath-contacting part; resilient means, normally holding said sliding element in its position farthest from said tip end; the said sliding element having a portion normally projecting outside said handle portion, and adapted to be manually operable, against the action of said resilient means.
Claim 34
Dependent Claim
57 words
A thermometer as set forth in claim 27, in which the said sheath has a length that is normally shorter than the distance between said sheath-contacting part and the outermost tip-end portion of the probe, and comprises resilient material permitting stretching of the sheath until the said inward end portion is in contact with said sheath-contacting part.
Claim 35
Dependent Claim
77 words
A thermometer as set forth in claim 20 further including voltage-responsive means to control the indicating means, comprising: counting means for measuring the values of said signal voltage, a slope generator; a voltage comparator for comparing the output voltage from said generator and the said signal voltage; and means actuated by output voltage from said comparator to stop operation of said counting means; and in which said indicating means indicates temperature in degrees and tenths of degrees.
Claim 36
Dependent Claim
141 words
A thermometer as set forth in claim 29, in which said indicating means comprises: three blocks having visible surfaces, with windows at said surfaces; three segmented members, one back of each of said windows, for providing light thru said windows and indicating tens, units and tenths of degrees; a block of substantially transparent material, for indicating the numeral ''''1'''' of 100 or more degrees, having a visible surface, a window in said surface, and a back surface that is inclined relative to said visible surface; an integral, unsegmented member back of said last-named window for providing light indicating ''''1'''' thru said window; a coat of black material covering said visible surface and the side surfaces of said last-named block, excepting at its window; and a coat of light-reflecting material on the said back surface of the last-named block, below its window.
Claim 37
Dependent Claim
64 words
A thermometer as set forth in claim 20 having supporting means that comprises: a board and container; means on said board for detachably holding said container thereon; means on the board for detachably holding thereon a group of disposable probe sheaths of the above-specified type; and means for detachably holding a sheet of paper on the board in position for recording thereon the temperature.
Claim 38
Dependent Claim
45 words
A thermometer as set forth in claim 31, in which said means for detachably holding said container and group on the board comprise a headed stud between adjacent ends of the container and group and spring-biased fasteners at other ends of the container and group.
Claim 39
Dependent Claim
26 words
A device as set forth in claim 31, in which said supporting means further comprises a strap adapted to go around the neck of an operator.
Claim 40
Dependent Claim
66 words
An electronic thermometer as set forth in claim 20, including thermometer-supporting means, in which said supporting means comprises: means for clasping and detachably holding said probe; a box for detachably storing a group of unused, disposable sheaths for said probe, comprising sockets, each of which is adapted to hold a sheath in position for manual insertion of the probe into the sheath and its surrounding socket.
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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) | 1976-04-30 | 1976-10-30 | 1977-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-30 | 1980-10-30 | 1981-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-30 | 1984-10-30 | 1985-05-01 | $7700.00 | Window Closed / Lapsed |