Patent attributes
A keyboard apparatus includes: a frame; keys each disposed pivotably with respect to the frame; pivot members each including: a support member disposed pivotably about a pivot shaft; and a structure connected to the support member at a position spaced apart from the pivot shaft, the structure having a specific gravity that is greater than that of the support member. A hole portion is formed in each of a first structure and a second structure, each of which is the structure of a corresponding one of a first pivot member and a second pivot member of at least two of the pivot members, such that a mass of the first structure and a mass of the second structure are different from each other. The hole portion of the first structure and the hole portion of the second structure are different from each other in shape.