Screw press having a shifting coupling and a continuously rotating flywheel

In a screw press including a shifting coupling for the press spindle having a spindle disk, means for continuously rotating a flywheel, coupling means operatively located between the flywheel and the spindle disk, a reaction mass coupled with the flywheel and a shifting mechanism dependent upon angular deceleration and controlled for the purpose of actuating the coupling means, the shifting mechanism comprising:

• (a) a hydraulically actuatable coupling means,
• (b) a hydraulically prestressed valve located between the reaction mass and a rotating coupling portion connected to the flywheel, and
• (c) means for hydraulically operating on the coupling means,
• (d) said prestressed valve being affected by the hydraulic pressure medium acting upon the coupling means,
• (e) the prestressed valve includes a cone, a shaft and a piston slidingly mounted on the shaft of the valve cone,
• (f) an abutment is secured to the shaft between a first and second spring,
• (g) the first spring acts directly on the piston,
• (h) the prestressed valve includes a pressure chamber, a restrictor and a cylinder chamber,
• (i) the restrictor connects the cylinder chamber of the piston to the valve pressure chamber.

In a screw press including a shifting coupling for the press spindle having a spindle disk, means for continuously rotating a flywheel, coupling means operatively located between the flywheel and the spindle disk, a reaction mass coupled with the flywheel and a shifting mechanism dependent upon angular deceleration and controlled for the purpose of actuating the coupling means, the shifting mechanism comprising:

• (a) a hydraulically actuata ble coupling means,
• (b) a hydraulically prestressed valve located between the reaction mass and a rotating coupling portion connected to the flywheel, and
• (c) means for hydraulically operating on the coupling means,
• (d) said prestressed valve being affected by the hydraulic pressure medium acting upon the coupling means,
• (e) there is a return line for the pressure medium which hydraulically operates the shifting mechanism,
• (f) said return line includes an annular channel for the pressure medium,
• (g) the annular channel comprises a U-shaped annular collar disposed on the press headpiece, and
• (h) an annular countercollar is disposed on the rotating coupling portion and acts to form a seal with the U-shaped annular collar.

A screw press comprising:

• (a) a flywheel drivable continuously in the same direction of rotation around a spindle,
• (b) coupling means operatively located between the flywheel and the spindle,
• (c) hydraulic control means for establishing a connection between the flywheel and the spindle only during a working stroke of the screw press,
• (d) a reaction mass connected for rotating with the flywheel to serve as a reaction and shifting mass,
• (e) upon an angle deceleration of the flywheel caused by the operation of the screw press, the reaction mass following its inertia forces moves in advance of the flywheel to cause a relief of the coupling means,
• (f) control means dependent upon angular deceleration is located between the flywheel and the reaction mass,
• (g) the coupling means including a coupling portion connected to the flywheel and carrying the reaction mass directly thereon,
• (h) said hydraulic control means including a pressure medium and a valve hydraulically prestressed in a discharge line of the pressure medium by the pressure existing in the coupling means,
• (i) the valve being located between radial projections located on the reaction mass and the coupling portion, and
• (j) the prestressed valve including effective surfaces, and in view of the action of the reaction mass and considering the coupling torque, said effective surfaces are in such a relationship that the response of the prestressed valve is taking place before the slipping of the coupling means begins.