The constant temperature valve core is a device that automatically adjusts the mixing ratio of cold and hot water, so that the temperature of the mixed water can be automatically maintained at the set temperature.
The first generation of constant temperature valve core uses wax constant temperature element (Wax Element).
The working principle of the paraffin temperature sensing component is to pour high-purity special paraffin into a small copper container, with a rubber sensing piece covering the container opening. Due to changes in water temperature, the volume of paraffin in the container also increases and shrinks. The sensing plate at the container mouth drives a spring to push the piston to adjust the mixing ratio of cold and hot water.
However, the paraffin constant temperature valve core has always had drawbacks such as slow reaction speed and excessive temperature overshoot. The instantaneous temperature overshoot value refers to the temperature that the thermostat, when adjusting the temperature, first momentarily exceeds the target temperature, and then returns to the target temperature. The instantaneous exceeding value of the paraffin constant temperature valve core is approximately 5 ℃~10 ℃.
The second generation constant temperature valve core uses Shape Memory Alloys (SMA) springs.
The most important component in the SMA constant temperature valve core is the shape memory alloy spring, which is made of nickel titanium (Ni Ti) alloy and has an effective working temperature range of 0 ℃ to 100 ℃.
The SMA constant temperature valve core has an extremely fast reaction speed, and the instantaneous temperature exceeding value can be controlled below 2 ℃. Moreover, the SMA constant temperature valve core has extremely sensitive response near 40 ℃, which can meet the needs of users for stepless fine tuning.
In the SMA constant temperature valve core, the shape memory alloy spring itself serves as a temperature sensing element and also has the function of pushing the piston to adjust the mixing of cold and hot water. Moreover, the mixed water can also pass through the spring, saving valuable space and making the constant temperature valve core more exquisite.
As a core device, the thermostatic valve core is widely used in thermostatic water heaters and thermostatic faucets.
When the water pressure of hot or cold water suddenly changes, or when the temperature of hot water suddenly changes, the constant temperature regulating valve core can automatically balance the water pressure of cold and hot water in a short period of time to maintain the stability of the outlet temperature, without the need for manual adjustment.