Temperature measuring device

A temperature Measuring Device comprising a fluid reservoir for thermal contact with the object whose temperature is to be measured, a generally tubular fluid-expansion chamber, a controllable valve-unit disposed between said reservoir and said chamber, and a working fluid contained within said reservoir;

• said control unit in a first position of orientation initially obstructing the flow of said fluid from said reservoir into said chamber and isolating said fluid in said reservoir;
• said control unit in a second position of orientation putting said reservoir in fluid flow communication with said chamber, the fluid pressure in said reservoir being greater than the pressure in said chamber while said valve-unit is in said second position of orientation;
• wherein said controllable valve-unit comprises a slot in said fluid-expansion chamber and a plug slidably inserted therein, said plug having at least one fluid conduit therethrough;
• said plug in said first position of valve-unit orientation obstructing flow communication between said reservoir and said chamber;
• said plug in said second position of valve-unit orientation having said conduit forming a fluid-flow passage between said reservoir and said chamber, such that said fluid will flow from said reservoir into said chamber due to said greater pressure in said reservoir;
• wherein said reservoir has at least one outlet orifice, wherein said chamber has at least one inlet orifice, and wherein each said plug conduit in said second position of orientation is respectively aligned with each said outlet orifice and each said inlet orifice so as to form fluid flow passages therebetween;
• wherein, prior to thermal contact with said object whose temperature is to be measured, said valve-unit is activated by moving said valve-unit from said first position of orientation to said second position so as to permit said working-fluid to flow from said reservoir into said chamber so as to stabilize at an equilibrium position related to the ambient temperature;
• and subsequently said reservoir is placed in said thermal contact with said object, such that said temperature of said fluid will be modulated to said temperature of said object, thereby causing a thermal volumetric change in said fluid which may be related to said temperature of said object;
• and wherein said fluid is caused to chemically react in or with said chamber so as to alter the optical opacity of said fluid in relation to said temperature of said object.