Patent ID: 8774873

Claim:
A case frame comprising: a main hole portion including a first plurality of holes in a first plate of the case frame; a second plurality of holes branched from the main hole portion and communicating with the main hole portion in the first plate; a third plurality of holes corresponding to the second plurality of holes in a second plate of the case frame; and at least one chamber formed between the second plate of the case frame and a board disposed below the second plate of the case frame, the at least one chamber comprising a first passage formed by a first one of the third plurality of holes and a second passage formed by a second one of the third plurality of holes; and wherein a first sound device and a second sound device are disposed in the at least one chamber, the first sound device being configured to communicate with the main hole portion via the first passage and the second sound device being configured to communicate with the main hole portion via the second passage.