Abstract: An apparatus for opening and closing the cover for a keyboard of a musical instrument including a rack and pinion mechanism to provide smooth sliding of the cover member. A rack and a pinion guide groove are integrally formed on each side of the musical instrument. A rotatable shaft includes at each end a pinion which engages with the rack. The pinion members are slidingly engaged on the shaft so that the guide members at each end of the shaft may be easily inserted into the guide grooves provided on the sides of the mechanism.

Abstract: A key apparatus is provided in which the resistance of the keys to being depressed is such that the touch feeling of a real piano key is simulated. A key is pivotally mounted so that rotation is performed in response to depression. A weighted lever and a weight embedded in the key serve to urge the key in the opposite rotational direction. A deformable element is arranged so that it contacts the key after the key has been depressed a predetermined distance. The resistance of the deformable element to being deformed initially increases as the key is depressed beyond the predetermined distance, and then decreases as the key is depressed further.