Drive Device for a Dual-Cylinder Slurry Pump and Method for Operating Said Pump

Abstract

The invention relates to a method for operating a drive device for a dual-cylinder slurry pump and to a drive device for a dual-cylinder slurry pump, comprising two drive cylinders that are actuated by means of a fluid ( 1, 2 ), said cylinders alternately charging a common delivery line with slurry, in particular concrete, via a pipe switch (RW), in particular indirectly by means of driven delivery cylinders (FR, FL). According to the invention, the pipe switch is likewise actuated by means of a fluid using an actuator cylinder (SZ) and as early as the final displacement of the piston of each drive cylinder in its stroke, prior to said piston reaching its final position, at least part of the fluid stream that is provided to actuate the drive cylinder is used to actuate the actuator cylinder.

1 . Method for operating a dual-cylinder slurry pump, preferably for conveying concrete, comprising two alternately actuated delivery cylinders (FL, FR), which charge a common delivery line with slurry via a switch (RW), wherein the delivery cylinders (FR, FL) are actuated via a drive cylinder ( 1 ,  2 ) by means of a fluid and the switch (RW) is actuated via an actuator cylinder also by means of a clued, wherein a first pump unit (P 1 ) is provided, whose fluid volume flow is provided by means of a first supply line (L 1 ) primarily to the drive cylinders ( 1 ,  2 ) and a second pump unit (P 2 ), whose fluid volume flow is provided by means of a second line (L 2 ) primarily to the actuator cylinder (SZ), characterized by the fact that, during the piston stroke of a drive cylinder ( 1 ,  2 ), at least some of the fluid volume flow of the second pump device (P 2 ) transfers to the fluid volume flow of the first pump unit (P 1 ) for the drive cylinders ( 1 ,  2 ).  
   
   
       2 . Method in accordance with  claim 1 , characterized by the fact that, the fluid volume flow in the second supply line to the swiveling cylinder (L 2 ) or a part thereof can transfer into the first supply line to the drive cylinders (L 1 ) via a link line in which a switching device is installed.  
   
   
       3 . Method in accordance with  claim 1 , characterized by the fact that, the fluid volume flow in the first supply line (L 1 ) is made alternately available to the first drive cylinder ( 1 ) or the second drive cylinder ( 2 ) by a switching valve ( 3 . 2 ).  
   
   
       4 . Method in accordance with  claim 1 , 
 characterized by the fact that, just before the final position of a drive cylinder ( 1 ,  2 ) is reached, the switching device blocks the link line between the supply lines (L 1 ) and (L 2 ), such that fluid volume flow can no longer transfer from the second supply line (L 2 ) into the first supply line (L 1 ).    
   
   
       5 . Method in accordance with  claim 1 , 
 characterized by the fact that, the final piston position in the drive cylinders ( 1 ,  2 ) is determined by means of a proximity switch, in order that the switching device may be driven accordingly.    
   
   
       6 . Method in accordance with  claim 1 , 
 characterized by the fact that, the fluid volume stream is generated by 1 or 2 pump devices (P 1 , P 2 ) each with one or more pumps.    
   
   
       7 . Method in accordance with  claim 1 , 
 characterized by the fact that, the fluid is hydraulic oil.    
   
   
       8 . Method in accordance with  claim 1 , 
 characterized by the fact that the drive cylinders ( 1 ,  2 ), the actuating cylinder (SZ) and/or the switching valves needed for operation are controlled hydraulically.    
   
   
       9 . Drive device for a dual-cylinder slurry pump with two drive cylinders ( 1 ,  2 ) that are actuated by means of a fluid, said cylinders alternately charging a common delivery line with slurry, especially concrete, via a switch (RW), especially a pipe switch, especially indirectly via driven delivery cylinders (FR, FL), with the pipe switch also being actuated via an actuating cylinder (SZ) by means of a fluid, especially for performing the method in accordance with any of the previous claims, with at least one pump device (P 1 , P 2 ) by means of which the fluid is provided via supply lines under working pressure to the drive cylinders and the actuating cylinder, wherein are provided a switching device ( 6 ) for diverting at least part of the fluid stream generated by at least one pump device to the actuating cylinder and a determination device (VFR, VFL) for locating at least one piston position of each drive cylinder, 
 characterized by the fact that, the termination device is designed such that the piston position in the final displacement region is determined before the final position of the stroke is reached and, after determination f the piston position, the switching device is actuated.    
   
   
       10 . Drive device in accordance with  claim 9 , 
 characterized by the fact that, a single pump device with one or more pumps for supplying the drive cylinders and the actuator cylinder is provided.    
   
   
       11 . Drive device in accordance with claims  9 , 
 characterized by the fact that, two pump devices (P 1 , P 2 ) are each provided with one or more pumps, wherein the first pump device is provided via a first supply line primarily for supplying the drive cylinders and the second pump device via a second supply line primarily for supplying the actuator cylinder, wherein between first and second supply line is provided a link line to the switching device, wherein the switching device facilitates supply to the drive cylinders through the second pump device and/or supply to the actuator cylinder through the first pump device.    
   
   
       12 . Drive device in accordance with  claim 9 , 
 characterized by the fact that, the fluid is hydraulic oil.    
   
   
       13 . Drive device in accordance with  claim 9 , 
 characterized by the fact that, the determining device (VFR, VFL) has one or more mechanical, electrical, or hydraulic sensors for determining the piston position.    
   
   
       14 . Drive device in accordance with  claim 9 , 
 characterized by the fact that, the determination device (VSZ) for determining the position of the piston of the actuator or swiveling cylinder of the pipe switch has one or more mechanical, electrical, or hydraulic sensors for determining the position of the actuator or swiveling cylinder.    
   
   
       15 . Drive device in accordance with  claim 9 , 
 characterized by the fact that, the drive cylinders ( 1 ,  2 ) are coupled hydraulically, such that only one or two sensors are provided at one of the drive cylinders for determining the piston position in the respective drive cylinders.    
   
   
       16 . Drive device in accordance with  claim 9 , 
 characterized by the fact that, the switching device is hydraulically controlled and especially comprises a switching valve ( 6 ).