body 321 b more firmly moreover the joining portion 40 may further include guide means for guiding joining positions of the hooks 41 and the socket shape of joining surface 42 referring to fig7 it is preferable that the position guiding means holds the first body 321 a and the second body 321 b so that the first body 321 a and the second body 321 b do not move in addition to a function for guiding joining positions of the hooks 41 and the joining surfaces 42 the position guiding means includes a guide piece 43 projected from a side of the first body 321 a and a guide piece receiver 44 on a side of the second body 321 b for receiving the guide piece 43 it is preferable that at least one guide piece 43 is formed adjacent to each of the hooks 41 it is preferable that the guide piece receiver 44 is formed within a space of the socket shaped joining surface 42 of the first body 321 a it is preferable that the guide piece 43 is formed to fit in the guide piece receiver 44 for preventing the first body 321 a and the second body 321 b coupled together from moving a process for coupling the coating guide having bodies joined together to the control panel will be described the pcb 32 is mounted on the coating guide 33 then the coating guide 33 is fastened to the control panel.