In this way, the substrate unit 40 (excluding portions of the extension portions 422) are housed in the first space S1, and portions of the extension portions 422 (leading end portions 422b) and portions of the connection members 50 (terminals 51) are housed in the second spaces S2. The case 1 according to the present embodiment is provided with a structure for draining water produced by condensation or the like in the first space S1 in which the substrate unit 40 is housed, or water that entered from the outside. This drainage structure has the following configuration. Note that the drainage structure described below is provided in a forward region on the right side in the width direction of the case 1, but this drainage structure may be provided in a forward region on the left side in the width direction, in a rearward region on the right side in the width direction, or in a rearward region on the left side in the width direction.

The following describes the drainage structure with reference to FIGS. 6 to 8 and the like. A channel 610 that extends from the first space S1 is formed in the first case body 10. The channel 60 includes a first channel portion 61 and a second channel portion 62. The first channel portion 61 is a channel with two ends that are connected to outlets, namely a first outlet 71 and a second outlet 72 (i.e., is a channel that is open to the outside). The second channel portion 62 is a channel with one end connected to the first space S1, and the other end connected to a midway portion (between the first outlet 71 and the second outlet 72) of the first channel portion 61.