Compaction roller

Abstract

The invention relates to a compaction roller having at least one rolling body with a vibratory drive which comprises a drivable exciter shaft with an unbalance. The shaft is mounted axially with respect to the rolling body and in the body. The unbalance, which comprises an unbalance cylinder arranged centrally with respect to the axis of the rolling body, is held by the exciter shaft and has an unbalance piston which can be adjusted hydraulically radially with respect to the axis of the rolling body by means of an adjusting device.

What is claimed is:  
     
         1 . A compaction roller having at least one rolling body with a vibratory drive; the vibratory drive being turned on to produce a vibration having an amplitude and a frequency and comprising a drivable exciter shaft mounted axially within said rolling body, an external adjusting device, a control valve and a hydraulic oil source; the exciter shaft having an unbalance device comprising an unbalance cylinder and an unbalance piston; the unbalance cylinder being held by the exciter shaft, centrally with respect to the axis of the rolling body; the unbalance piston being hydraulically radially adjustable with respect to the axis of the rolling body; the adjusting device being in fluid communication with the unbalance cylinder through a bore in the exciter shaft, the adjusting device supplying hydraulic fluid in a controlled manner to infinitely variably adapt the amplitude of the vibration to paving situations; the adjusting device having an actuating cylinder and an actuating piston, the actuating cylinder defining a chamber, the actuating piston being disposed within the chamber, the chamber of the actuating cylinder being in fluid communication with the unbalance cylinder; an oil passage extending from the actuating cylinder to the hydraulic oil source, the control valve being disposed in the oil passage; the valve being moveable between open and shut positions, the valve shutting when the unbalance piston is in a radially central position, whereby moving the unbalance piston from the central position increases or decreases the amplitude of the vibration.  
     
     
         2 . The compaction roller of  claim 1 , wherein the control valve shuts when the vibration has a minimum operating frequency.  
     
     
         3 . The compaction roller of  claim 1 , wherein the control valve opens to provide fluid communication between the unbalance cylinder and the hydraulic oil source after the vibratory drive has been turned off.  
     
     
         4 . The compaction roller of  claim 3 , wherein the control valve provides fluid communication between the actuating cylinder and the hydraulic oil source after the vibratory drive has been turned off.  
     
     
         5 . The compaction roller of  claim 3 , wherein the actuating piston is moveable between extended and retracted positions within the actuating cylinder, the control valve being openable when the actuating piston is in the retracted position.  
     
     
         6 . The compaction roller of  claim 4 , wherein the actuating piston is moveable between extended and retracted positions within the actuating cylinder, the control valve being openable when the actuating piston is in the retracted position.  
     
     
         7 . The compaction roller of  claim 5 , wherein when the unbalance cylinder is filled with hydraulic oil, the actuating piston can be moved to the extended position.  
     
     
         8 . The compaction roller of  claim 6 , wherein when the unbalance cylinder is filled with hydraulic oil, the actuating piston can be moved to the extended position.  
     
     
         9 . The compaction roller of  claim 1 , the vibratory drive further comprising a rotary bushing connecting the unbalance cylinder to the adjusting device, the rotary bushing being supported on the rolling body by a damping element.  
     
     
         10 . The compaction roller of  claim 9 , the vibratory drive further comprising a tube, a first piston disposed at a first end of the tube, and a second piston disposed at a second end of the tube, the first piston being axially moveably, rotationally fixedly connected to the rotary bushing, the second piston being axially moveably, rotationally fixedly connected to the exciter shaft.  
     
     
         11 . The compaction roller of  claim 1 , wherein the actuating piston is mechanically or hydraulically adjustable.  
     
     
         12 . The compaction roller of  claim 11 , wherein the vibratory drive further comprises sensory means for monitoring the position of the actuating piston.  
     
     
         13 . The compaction roller of  claim 1 , the vibratory device further comprising means for measuring a compaction performance of the rolling body and means for controlling the adjusting device as a function of a measurement of the compaction performance of the rolling body.  
     
     
         14 . The compaction roller of  claim 1 , wherein the unbalance piston is filled with a heavy metal.