Patent ID: 7849873

Claim:
A heater unit to be mounted on a valve having flow path forming sections including a valve body connected to a fluid piping system through joints, and having an actuator connected to the valve body, the valve being a two-way valve, in which the valve body is placed between a pair of pipes, and connected to the pipes through a pair of joints and sleeves, the unit comprising: a main body constructed in the form of a housing having pipe through-holes and an actuator exposing opening; and a heater unit in the main body, wherein the heater unit comprises: a direct heating section configured to heat the body of the valve through direct contact heating; and a radiant heating section, surrounding the direct heating section, and extending to an area of the flow path forming sections, excluding an area which is brought into direct contact with the direct heating sections, the pair of joints and a part of each of the sleeves, enclosed by the main body, configured to heat the inside of the main body by radiant heat; wherein each of the pipe through-holes has a diameter for receiving each of the sleeves, and the flow path forming sections including the body, the whole of the pair of the joints, and the part of the sleeves are entirely covered by the main body so that only the residual areas of the sleeves and the fluid piping system is exposed from the pipe through-holes, and the area extending from the part of one sleeve to the part of the other sleeve excluding the area which is brought into direct contact with the direct heating sections, enclosed by the main body, are constructed so as to be heated by the radiant heat from the radiant heating section.