Strain detecting device and diagnosing device

A strain detecting device comprising:

• (i) a sensor portion for detecting heat flux;
• and
• (ii) an elastic deformation member covering the sensor portion, wherein the elastic deformation member generates heat when it is compressed, while the elastic deformation member absorbs heat when it is expanded,
• wherein the sensor portion includes a first and a second heat flux sensors, each of which has;
• a first sensor surface formed on a side of the heat flux sensor;
• and
• a second sensor surface formed on another side of the heat flux sensor opposite to the first sensor surface,
• wherein each of the heat flux sensors outputs a first sensor signal having a positive polarity when the heat flux passes through the heat flux sensor in a direction from the first sensor surface to the second sensor surface, while each of the heat flux sensors outputs a second sensor signal having a negative polarity when the heat flux passes through the heat flux sensor in a reversed direction from the second sensor surface to the first sensor surface,
• wherein the sensor portion includes a heat absorbing member interposed between the first and the second heat flux sensors and having a predetermined heat capacity, and
• wherein the first and the second heat flux sensors are arranged in such a way that the first sensor surfaces of the respective heat flux sensors are opposed to each other across the heat absorbing member, and each of the heat flux sensors outputs the sensor signal depending on the heat flux generated by deformation of the elastic deformation member in such a way that a sensor signal level is changed for a unit time depending on the heat flux passing through the heat flux sensor.