| 摘要 |
There is disclosed a solenoid-dashpot assembly for actuating the foot pedals of a player piano. A solenoid having an armature shaft extending beyond the coil area of the solenoid receives a piston element, which, in turn, has an O-ring which co-acts with a dashpot cylinder. Constricted air passage elements are formed in the piston element and are provided with relatively large air passages which have mufflers thereon so that no sound is made when air ingresses or egresses through these constricted passages due to actuation and deactuation of the solenoid. To silence both ends of travel of the solenoid armature, the solenoid is mounted above a base plate on a mounting bracket and the solenoid armature carries a pad extending from a side opposite the dashpot. The base plate has an adjustable pad thereon opposite the pad on the solenoid armature so that on actuation and deactuation of the solenoid, there are no noise generating, hard surface to hard surface contacts at either end point of solenoid armature movement. These elements are provided so as to enable the solenoid dashpot assembly to more closely approximate the action of the piano player in the depressing the pedals of the piano, and at the same time, are almost completely silent. |
