Disposable speculum for tympanic thermometer

• US 3,949,740 A
• Filed: 12/16/1974
• Issued: 04/13/1976
• Est. Priority Date: 08/23/1973
• Status: Expired due to Term

• Current Assignee: Products International Marketing
• Original Assignee: Products International Marketing
• Inventors: Twentier, Max E.
• Primary Examiner(s): Michell, Robert W.
• Assistant Examiner(s): Layton, Henry S.
• Application Number:
  US05/533,138
• Time in Patent Office: 484 Days
• Field of Search: 128/3, 128/6, 128/4, 128/9
• US Class Current: 600/200
• CPC Class Codes: A61B 1/00142 with means for preventing contamination, e.g. by using a sanitary sheath
• CPC Class Codes: A61B 1/227 for ears, i.e. otoscopes
• CPC Class Codes: A61B 5/4863 Measuring or inducing nystagmus
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/021 Probe covers for thermometers, e.g. tympanic thermometers; Containers for probe covers; Disposable probes
• CPC Class Codes: G01J 5/05 Means for preventing contamination of the components of the optical system; Means for preventing obstruction of the radiation path

Abstract

A disposable plastic speculum is used on an infrared sensing thermometer used by placing it in the patient'"'"'s ear for sensing body temperature through the tympanic membrane. The speculum has the general shape of a funnel with relatively shallow and relatively steep tapered frustoconical sections. The speculum is placed on a speculum retainer on the thermometer for use. The exterior of the speculum retainer has the general shape of interior of the speculum and includes a peripheral enlargement near its smaller end. When the speculum is placed on the retainer it is stretched by the enlargement and thereby retained in place. The speculum is made of a plastic having limited resistance to stress cracking so that the stretched portion over the enlargement cracks during retention on the speculum retainer. Since the speculum thus inherently destroys itself, it is assured that the speculum will be discarded and a new one used for each patient.

Claims

1. A combination of a speculum retainer and a speculum,

the speculum retainer comprising a rigid member having an axial interior passage and a generally frustoconical exterior with a peripheral enlargement nearer its smaller end and a reduced cross-section portion between the enlarged portion and the wider portion of the exterior;

the speculum comprising a generally frustoconical plastic member having a principal portion interiorly complementary to the exterior of the retainer and a minor portion elastically stretchable to conform to the enlargement without exceeding the fast tensile strength of the plastic in the stretched portion of the speculum, and wherein the stretching of the speculum by the enlargement induces stress cracking in the speculum in no more than a few minutes.

2. A combination of a speculum retainer and a speculum,

the speculum retainer comprising a rigid member having an axial interior passage and a generally frustoconical exterior with a peripheral enlargement nearer its smaller end and a reduced cross-section portion between the enlarged portion and the wider portion of the exterior;

the speculum comprising a generally frustoconical plastic member formed of a plastic having a resistance to stress cracking not greater than polyethylene having a melt index of less than about 30, and having a principal portion interiorly complementary to the exterior of the retainer and a minor portion elastically stretchable to conform to the enlargement without exceeding the fast tensile strength of the plastic in the stretched portion of the speculum; and

wherein

the peripheral enlargement is sufficiently larger than the minor portion of the speculum that it induces stress cracking in the speculum in no more than a few minutes.

3. A disposable speculum as defined in claim 2 wherein the extending portion comprises an inwardly directed lip adjacent the smaller end of the speculum for covering the end of the retainer.

4. A combination comprising:

a disposable speculum including a first hollow, generally frustoconical base section having a relatively shallow taper;

a second hollow generally frustoconical nose section having a relatively steep taper, the base of the nose section being essentially a continuation of the smaller end of the base section;

said nose section being formed of a plastic having a resistance to stress cracking not greater than polyethylene having a melt index of less than about 30 and sufficiently thin relatively nearer its small end to have a peripheral elongation of about 20% without exceeding the fast tensile strength of the plastic; and

a speculum retainer in the form of a rigid member having an axial interior passage and a generally frustoconical exterior with a peripheral enlargement nearer its smaller end and a reduced cross section portion between the enlarged portion and the wider portion of the exterior, the exterior of the rigid member being complementary to the interior of the disposable speculum except for the peripheral enlargement which has a larger diameter than the speculum for elastic stretching thereof and wherein the peripheral enlargement is sufficiently larger than the speculum that it induces stress cracking in the speculum in no more than a few minutes.

5. A combination as defined in claim 4 wherein the speculum includes a portion extending beyond the end of the retainer for inhibiting contamination thereof.