Patent ID: 6439374
Filing Date: 2002-08-27
Classification: B06B,B07B,B65G

Abstract:
An oscillatory drive unit for use in an oscillating system to be oscillated substantially at the resonance point of the oscillating system, wherein the oscillating system includes a mass to be oscillated and a countermass, to which the mass is connected by resilient coupling means,said oscillatory drive unit comprising: a piston-cylinder-component for energization by a gas under pressure, the cylinder of the piston-cylinder-component being adapted to be operatively connected to either the mass or the countermass and the piston of the piston cylinder component having connecting means being adapted to be operatively connected to the respective other of the mass or countermass, wherein, the piston-cylinder-component comprises a single cylinder chamber being defined by an inner end wall and the inner side wall of the cylinder and a first end face of the piston, the opposite or second end face of the piston being provided with said connecting means, the piston is arranged for reciprocal movement between a first end position in which the first end face of the piston is close to the inner end wall of the cylinder and a second end position in which the first end face of the piston is most remote from the inner end wall of the cylinder, the piston-cylinder-component has inlet means for the gas under pressure, such inlet means being operative to introduce gas under pressure into the cylinder chamber within an energizing range of piston positions being defined by a first energizing position and a second energizing position of the piston, the first energizing position being closer to the cylinder end wall than the second energizing position, the piston-cylinder-component has venting means for venting the cylinder chamber to the environment, which venting means are operative within a venting range of piston positions being defined by a first venting position and a second venting position of the piston, the first venting position being closer to the cylinder end wall than the second venting position, the energizing range of piston positions being close to or including the first end position of the piston, and the venting range of piston positions being close to or including the second end position of the piston, the actual reversal points of movement of the piston adjusting themselves under operating conditions of the oscillating system.