Core body temperature device and system
Aspects of the present disclosure relate to a temperature device including a flexible substrate, and an electrical circuit on a surface of the flexible substrate, the electrical circuit including a heater element having an outer perimeter and an inner perimeter, the inner perimeter surrounding a zone of the surface, the zone is thermally distinct from the heater element, wherein the heater element has a first dimension defining the outer perimeter and a second dimension defining the inner perimeter, wherein a ratio of the first dimension to a second dimension is no greater than 2.1:1, a first thermal sensor disposed in the zone, a second thermal sensor disposed outside of the heater element, a plurality of electrical pads disposed outside of the heater element, and a plurality of conductive traces connecting the first and second thermal sensors and the heater element with the plurality of electrical pads.
1 . A temperature device, comprising:
a flexible substrate, comprising:
a circular center section;
a tail section; and
a tab section;
an electrical circuit on a surface of the flexible substrate, the electrical circuit comprising:
a heater element on the circular center section having an outer perimeter and an inner perimeter, wherein the inner perimeter surrounds a zone of the surface that is thermally distinct from the heater element;
a first thermal sensor disposed in the zone;
a second thermal sensor disposed outside the heater element on the tail section;
a plurality of electrical pads disposed outside the heater element on the tab section; and
a plurality of conductive traces, wherein each of the plurality of conductive traces connects one of the first thermal sensor, the second thermal sensor, and the heater element with a different one of the plurality of electrical pads;
a first insulator confronting a first side of the flexible substrate, wherein the first insulator is to contact the skin of a patient; and
a second insulator confronting a second side of the flexible substrate, wherein the second insulator comprises:
a first region with a first thermal resistance disposed over the zone of the surface of the flexible substrate to allow a portion of heat generated by the heater element to escape and reduce thermal interference with the first thermal sensor; and
at least one adjacent region with a second thermal resistance greater than the first thermal resistance located adjacent to the first region and over the heater element.
2 . The temperature device of claim 1 , wherein the lower thermal resistance region is thinner than the at least one adjacent region.
3 . The temperature device of claim 1 , wherein the second insulator is ring shaped.
4 . The temperature device of claim 1 , wherein an inner perimeter of the second insulator overlaps the inner perimeter of the heater element.
5 . The temperature device of claim 1 , wherein the second insulator has a ring shape, and wherein the lower thermal resistance region comprises a material having has a thermal conductivity of at least 100 W/(m K).
6 . The temperature device of claim 1 , wherein the second insulator has a ring shape, and wherein the lower thermal resistance region comprises a hole.
7 . The temperature device of claim 1 , wherein the heater element is a heater trace defined by wires.
8 . The temperature device of claim 6 , wherein the at least one adjacent region has a first thermal conductivity, wherein the second insulator further comprises a material disposed in the hole, and wherein the material has a second thermal conductivity that is greater than the first thermal conductivity.
9 . The temperature device of claim 1 , further comprising a computing device disposed on the second insulator.
10 . The temperature device of claim 9 , wherein the computing device provides a stiffening layer to the second insulator.
11 . The temperature device of claim 9 , wherein the computing device comprises a printed circuit board and a battery.
12 . A temperature device, comprising:
a substrate, comprising:
a center section; and
a tail;
a heater on the center section having an outer perimeter and an inner perimeter, wherein the inner perimeter defines a zone on the center section;
a first thermal sensor disposed in the zone;
a second thermal sensor disposed on the tail;
a first insulator confronting a first side of the substrate, wherein the first insulator is to contact skin of a patient; and
a second insulator confronting a second side of the substrate, the second insulator comprising:
a first region with a first thermal resistance, the first region comprising:
a first surface confronting the heater; and
a second surface facing away from the heater, wherein the first and second surfaces define a first thickness of the first region; and
a second region with a second thermal resistance less than the first thermal resistance, the second region comprising:
a third surface confronting the first thermal sensor and stepped down relative to the first surface such that the first and third surfaces are not flush; and
a fourth surface facing away from the first thermal sensor and stepped down relative to the second surface such that the second and fourth surfaces are not flush.
13 . The temperature device of claim 12 , wherein the second region allows a portion of heat generated by the heater to escape and reduce thermal interference with the first thermal sensor.
14 . A temperature device, comprising:
a flexible substrate, comprising:
a center section; and
a tail;
a heater on the center section having an outer perimeter and an inner perimeter, wherein the inner perimeter defines a zone on the center section;
a first thermal sensor disposed in the zone;
a second thermal sensor disposed on the tail;
a first insulator to confront a first side of the flexible substrate and to contact skin of a patient; and
a second insulator to confront a second side of the flexible substrate, wherein the second insulator comprises:
a first region with a first thermal resistance located over the heater; and
a second region with a second thermal resistance less than the first thermal resistance, adjacent to the first region, defined by a hole therethrough that is alignable with the first thermal sensor to allow a portion of heat generated by the heater to escape and reduce thermal interference with the first thermal sensor.
15 . The temperature device of claim 14 , wherein the second insulator comprises an inner perimeter defining the hole and an outer perimeter, wherein a first distance is defined between the inner and outer perimeters of the heater second insulator, and wherein a second distance is defined between the inner and outer perimeters of the heater.
16 . The temperature device of claim 15 , wherein the first distance is greater than the second distance.
17 . The temperature device of claim 15 , wherein the first distance is less than the second distance.
18 . The temperature device of claim 15 , wherein the first distance is equal to the second distance.