Electronic thermometer

• US 3,905,232 A
• Filed: 10/05/1973
• Issued: 09/16/1975
• Est. Priority Date: 10/05/1973
• Status: Expired due to Term

• Current Assignee: New Ivac, Inc.
• Original Assignee: Wallace L. Knute
• Inventors: Knute, Wallace L.
• Primary Examiner(s): Queisser, Richard C.
• Assistant Examiner(s): Shoon, Frederick
• Application Number:
  US05/403,898
• Time in Patent Office: 711 Days
• Field of Search: 73/362AR
• US Class Current: 374/158
• CPC Class Codes: G01K 1/16 Special arrangements for conducting heat from the object to the sensitive element
• CPC Class Codes: G01K 13/20 Clinical contact thermometers for use with humans or animals
• CPC Class Codes: G01K 7/00 Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat giving results other than momentary value of temperature G01K3/00 ; Power supply therefor, e.g. using thermoelectric elements

Abstract

Apparatus for automatically actuating and deactuating the electrical circuitry of an electronic thermometer of the type which uses a temperature sensing probe and disposable probe covers in the measurement of body temperature. The probe projects fowardly from a thermometer housing and a tubular probe cover is installed by driving the probe rearwardly into the housing, against resilient means, until a retaining means on the housing engages the cover. The probe is rigidly attached to a probe ejection shaft extending through the housing and movable with the probe to a rearward position during installation of the probe cover and to a forward position to eject the cover. The ejection shaft has a camming surface which cooperates with an actuator arm of a thermometer power supply microswitch located within the housing, to cam the microswitch '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' as the probe cover is installed, and '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' as the probe cover is ejected by manually pushing the ejection shaft forward.

Claims

1. For use with an electronic thermometer employing a temperature sensing probe and removable probe cover, automatic actuation and deactuation means, comprising in combination:

a switch for switching the thermometer on and off; and

means responsive to installation of a probe cover on the temperature sensing probe, for placing said switch in an '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' condition, said means also being responsive to ejection of the probe cover for returning said switch to an <

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off'"'"''"'"''"'"''"'"' condition.

2. A combination as set forth in claim 1, wherein said means includes a cam for selectively engaging said switch.

3. A combination as set forth in claim 1, wherein:

said switch includes an actuator arm; and

said means for placing said switch in an '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' condition includes a cam coupled to the temperature sensing probe and positioned to cam said actuator arm to the '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' condition on a rearward movement of said cam, whereby installation of a probe cover is effected by moving the probe and probe cover rearwardly until the probe cover reaches an installed position.

4. A combination as set forth in claim 3, wherein:

said cam includes a camming surface on a shaft attached to the probe and extending rearwardly therefrom.

5. For use with an electronic thermometer employing a temperature sensing probe and removable probe cover, automatic actuation and deactuation means, comprising in combination:

a switch for switching the thermometer on and off, said switch having an actuator arm movable between an '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' condition and an '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' condition, said actuator arm being normally biased toward the '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' condition; and

means responsive to installation of a probe cover on the temperature sensing probe, for moving said switch actuator arm to the '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' condition, said means including a shaft attached to the probe and extending rearwardly therefrom, said shaft having a camming surface positioned to cam said actuator arm to the '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' position on a rearward movement of the probe;

said shaft also being manually movable in a forward direction to eject the cover from the thermometer and to allow said biased actuator arm to return to the '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' condition.

6. In an electronic thermometer enclosed in a single housing and having an integrally mounted temperature sensing probe, a removable probe cover, and probe cover retaining means, the improvement comprising;

a cam-operated switch connected between the thermometer and its power source;

camming means connected to the probe for camming said switch to an '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' position automatically as the probe is moved inwardly with respect to the housing to permit engagement of the probe cover with its retaining means;

manually operable probe cover ejection means, connected with said camming means and said probe, for ejecting the probe cover from the probe by applying an outward force on the probe to free the probe cover from its retaining means, and for simultaneously moving said camming means to automatically cam said switch to an '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' position.

7. The improvement set forth in claim 6, and further including:

resilient means for urging said camming means and the probe outwardly, thereby to maintain said switch in the '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' position if no probe cover is installed and to urge the probe against the probe cover when a cover is installed.

8. The improvement set forth in claim 6, wherein:

said manually operable probe cover ejection means include an ejector button extending from the thermometer housing.

9. In an electronic thermometer enclosed in a single housing and having an integrally mounted temperature sensing probe, a disposable probe cover, a self-contained power source, and probe cover retaining means, the improvement comprising:

a cam-operated switch connected to control electrical current flow from the power source;

a switch actuator attached to the probe and having an integral camming surface arranged to cam said switch between an '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' position and an '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' position as said switch actuator is moved with said probe between an extended position and a retracted position; and

a manually operable ejection control mechanically linked with said switch actuator so that operation of said control results in movement of said switch actuator and the probe to the extended position, thereby camming said switch to the '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' position and ejecting the probe cover from its retaining means.

10. The improvement set forth in claim 9, wherein said manually operated ejection control is a button on the housing rigidly connected with said switch actuator to form an integral shaft extending through the housing.

11. The improvement set forth in claim 10, further including resilient means for urging said shaft and the attached probe toward its extended position.

12. In a probe unit for an electronic thermometer, the probe unit having a temperature sensing probe, a replaceable probe cover, and probe cover retaining means, the improvement comprising:

a cam-operated switch housed in the probe unit and electrically connected with the thermometer for switching it on and off;

camming means rigidly connected with the probe for camming said switch to an '"'"''"'"''"'"''"'"'on'"'"''"'"''"'"''"'"' position as the probe is moved inwardly with respect to the probe unit to allow engagement of the probe cover with its retaining means; and

probe cover ejection means manually operable to move the probe, camming means, and probe cover outwardly with respect to the probe unit, and thereby to eject the probe cover and, in substantially the same action, cam said switch to an '"'"''"'"''"'"''"'"'off'"'"''"'"''"'"''"'"' position.