Patent ID: 7299090

Claim:
An arrangement for measuring the body temperature of a living organism, the arrangement comprising: a housing; a first sensor mounted in said housing and disposed in contact engagement with the skin of the living organism for measuring a first temperature; a second sensor mounted in said housing for measuring a second temperature; said first sensor having a side facing away from said skin; said second sensor being mounted at a distance from said side of said first sensor; insulating means disposed between said first and second sensors for thermally insulating said first and second sensors from each other and conducting a thermal flow therebetween from which a thermal loss flow (q sa ) branches off while measuring said body temperature; compensation means for determining or estimating said thermal loss flow (q sa ); an evaluation unit operatively connected to said compensation means so as to permit consideration of said thermal loss flow (q sa ) thereby increasing the accuracy of the measurement of said body temperature; wherein said evaluation unit determines said body temperature with the aid of a formula and said compensation means is a compensation term which expands said formula; wherein said housing has an outer wall; and, said compensation term is dependent upon at least one of a boundary temperature (t sa ) at said outer wall of said housing and a thermal conductance (α) between said housing and the ambient (U); said arrangement further comprising a third sensor mounted in the region of said outer wall for measuring said boundary temperature and said compensation term being formed in dependence upon said boundary temperature (t sa ) measured by said third sensor; wherein said compensation term is formed exclusively by coupling of constant parameters (K iso , K g , A iso — m , A s , α, K s ) and the skin temperature (T h1 ) measured by said first sensor and the further temperature (T h2 ) measured by said second sensor and said formula for measuring body temperature (T c ′) including said compensation term is given by: T c ′=T h1 +K s /K g *( T h1 - T h2 )+(( K iso /K g )*( A iso — m /A s )*((( T h1 - T h2 )/2)- t sa ))→14 wherein: K s =thermal conductivity coefficient of said sensor housing; K g =thermal conductivity coefficient of human tissue; K iso =thermal conductivity coefficient of the outer insulation; A iso — m =surface area of the outer insulation (same elevation as the insulation between the sensors); A s =end face of the sensor having the diameter of the insulation; t sa =boundary temperature at the outer surface of the insulation as measured by said third temperature sensor; 14=said compensation term; and, wherein, said constant parameter (α) is a thermal conductance constant (α) representing the thermal conductance between said outer wall of said housing and the ambient (U).