is for enhancing accuracy of alignment of the button portions 31 c with the input devices 32 a by placing the input devices 32 a closer to the button portions 31 c of the control panel 31 at the time the coating guide 32 is coupled to the control panel 31 the joining portion 40 will be described in more detail with reference to fig7 the joining portion 40 includes hooks 41 on a side of the second body 321 b of the plurality of individual bodies 321 a and 321 b and a joining surface 42 having hook holes 42 a on a side of the first body 321 a which is to be coupled to the second body 321 b for holding the hooks 41 on the second body 321 b though the embodiment shows the hooks 41 on the second body 321 b and the joining surface 42 on the first body 321 a it does not matters even if positions of the hooks 41 and the joining surface 42 are interchanged it is preferable that numbers of the hooks 41 and the joining surfaces 42 are at least one respectively it is preferable that at least one hook hole 42 a is formed in the joining surface 42 for enabling hooking of a plurality of hooks 41 to the joining surface 42 the embodiment shows three hooks 41 on the side of the second body 321 b the joining surface 42 has spaces for receiving the hooks 41 respectively and sockets each with a hook hole 42 a in a circumference for holding the hooks 41 it is preferable that the hooks 41 have holding directions different from adjacent one more preferably as shown in fig7 opposite to adjacent one the socket shape of.